"But seeing they could not See; hearing they could not Hear"
“The views expressed herein are those of the author and do not necessarily represent those of the National Weather Service or affiliate/related organizations. Please consult .gov sites for official information”

"From its chamber comes the whirlwind, and cold from the scattering winds." - Job 37:9.

"The wind blows to the south and turns to the north; round and round it goes, ever returning on its course".

Wednesday, February 29, 2012

Above Normal Temperatures Through Saturday

Visible satellite image shows were the morning fog (some quite dense) exists this Wednesday morning. The layer of inversion supporting the fog appears to be fairly thin, so it should be burning off late morning. As the fog lifts, it will manifest as clouds across the northern 2/3 of the state which will press toward the east to ENE through mid-morning 

TODAY: Morning fog in many locations, no temperature issues. High pressure at the surface (per light wind) and in the mid-levels supplied by ample shallow moisture is the culprit for the fog, with that moisture being trapped by warmer air just above the ground. The inversion of temperatures per morning sounding and short-run model (RUC) forecast soundings indicate this inversion is shallow so the fog should be able to break up as heating occurs. With light winds aloft from near calm toward the east, low clouds could manifest as the fog breaks up and advect toward the east..but those too will thin out some working toward early afternoon. Otherwise, most locations will see the low 80Fs today with inland areas into the mid-80Fs easily with light inland winds and SE winds near the immediate coast (but light).

The blue zig-zag lines are a depiction of surface axis or ridges of high pressure centers. Not that the fog is closer to the location of those lines.

THIS WEEKEND:  Prior to the weekend, namely Thursday-Saturday warmer yet still with highs most areas in the mid-80Fs and perhaps a few upper 80Fs as well, partly cloudy sky. Winds light again this evening become SSW-SW Thursday through Saturday. A cold front is approaching and should be able to tweak through sometime very early Sunday near daybreak and continue south to the Straits before becoming absorbed once again by high pressure (as was the case with the previous frontal boundary), after which time we will experience 2-3 days of slightly below normal temperatures but nothing earth-shattering (into Tuesday).

It appears there will be a cloudy and possibly showery period along with the boundary and behind it mainly, to persist a good  6-12 hours after cold frontal passage (Sunday).

Perhaps two days of highs reaching 70F or not quite even that, but morning lows will not get below the mid 40Fs (North interior), toward low 50Fs immediate East Coast Central to warmer yet all of South Florida.

NEXT WEDNESDAY:  Wind will become more onshore toward early-mid week and strengthen. Plentiful stratocumulus clouds and low topped showers could begin by Tuesday, especially toward Wednesday. From that point on it appears a more synoptic (large scale) pattern is to emerge for the U.S. So far, no cold air on the way other than the upcoming cool spell, but rain chances could pick up significantly with the on-set of stronger onshore winds mid-late week next week and beyond prior to the next front. Looks more like 'late fall' type pattern as opposed to early spring.

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Sunday, February 26, 2012

Generous Rain/Thunder Chances Monday - Is 'Winter' Over for South Half?

TODAY'S 500 mb/millibar (20,000 ft level)  wind forecast for this afternoon. Continuity  shows that the closed low over Mexico as mentioned in previous posts is no longer evident today, but instead is shown as a mere 'trough' (red line) moving across the northern Gulf Coast. Extensive cloudiness and showers combined with 'evaporative cooling' could keep temperatures in the mid-40Fs to lower 50Fs near I-10. Chance of rain/showers/sprinkles most likely in green, and minimally  'possible' as far south as SR 520 later today and early this evening, albeit not extensively so. Evaporative cooling is caused by rain falling through cold , dry air, evaporating into the drier air toward the ground but causing the air temperature to remain much cooler if not fall more so than would otherwise be expected.

TODAY: Major "Yuck" factor along I-10 today looks to be the agreed upon consensus in model guidance. Extensive cloud cover as short wave mid-upper level trough crosses this area with embedded rain showers, some possibly moderately heavy later today. There is no instability in this fast moving parade of disturbed moisture, and dew points remain very low. Thus, as rain falls in to the dry air it will drag down cold air which will evaporate 'some' of the rain and cause air temperatures to remain relatively low.

The first image was for the  500 millibar (mb), around 20,000 feet aloft ,  level winds. This is for the same time frame at ground level. Breezy ENE-E winds most of today and damp. The low is still evident in the SW Gulf but will wash out later tomorrow. The old front is sketched in (perhaps too far south toward the Florida Straits), but either way..whatever is left of it will work north tomorrow along to where the dotted black line is shown and eventually even further north. The focus of rain will be nearer that boundary...but also out over the Gulf Stream waters east of Central Florida. 
Meanwhile further south of the better rain chances today, ENE wind most of today becoming easterly tonight and eventually ESE on Monday. There is a small chance of rain as far south as the MLB toward SR 520 line, but the gradient of rain to 'no rain' line will be closer toward I-4 on the East Side of the state toward the Brooksville area on the west coast. Highs today in the mid-upper 60Fs most of central due to cloud coverage and  recovery from the meager cold frontal passage the other day. Low-Mid 70Fs more likely toward South Central and all of South Florida. Some showers possible over the Keys for the first part of the day as well.

MONDAY: Cloud coverage continues, so over night lows to remain in the low-mid 60Fs most areas. The area of low pressure that was in the SW Gulf will begin to break up later today..and bits and pieces of 'energy' (vorticity) will traverse across the state as a result after or near daybreak and through the day within a flow similar to what is shown in the top image (above) from west to east.

The main focus of energy so far is depicted to cross those areas that will not be in the rain today. Thus, everyone gets a shot at the rain between today and Monday.  The main difference tomorrow will be that instability will be much more sufficient to make for a chance of thunder most anywhere from North Central through most of South Florida, but South Central to Central seems so far to be the 'target area' for thunder.

This is a FORECAST of jet stream winds on Monday. Note the divergence of winds (separation) over Central Florida. This area is also expected to receive the brunt of 'energy'. With surface based CAPE (Convective Available Potential Energy) approaching 1000 units or more and temperatures in the mid-upper 70Fs inland showers/thunder possible in the orange zone most likely. Purple is where an even better chance exists, especially out over the Gulf Stream waters EAST of the Cape Canaveral area. On shore flow could 'exasperate' the rainfall potential from far Eastern Flagler  County southward to Martin County near the A1A corridor.    
There is a chance some heavier rainfall could occur along the SW Coast as well as the easterly low level flow stacks up against the mid-upper level westerlies. There is a large disagreement in early morning model guidance concerning that possibility.

Either way, the 'pool' of moisture as well as the 'energy' responsible for Monday's rain chance is all expected to pull off to the east before sunset although not entirely. Realizing that this post for today is based on data spit out at 2AM Sunday morning based on real-time information from 8pm (eastern) last night, much refinement as to timing and rain location details is desired, personally; however, based on the continuity between models this morning from previous runs, there has been little change since yesterday afternoon's results in model output...saying  something for consistency's sake.

BEYOND: There is a chance of showers and maybe some thunder on Tuesday interior and west side Central and South later in the afternoon, but elsewhere it will continue to warm toward the 80F mark each and everyday, particularly nearly statewide  by Thursday. There is no large significant 'drying' trend as far as clouds from time to time is concerned; thus, anyone anywhere could be in and out of some clouds from time to time, anytime. Wind will become southerly to eventually SSW-SW by Thursday/Friday time frame at which point east coast temperatures will possibly reach the mid 80Fs , and maybe more so depending on cloud coverage. The next frontal boundary poised for next weekend may not even make it beyond Central Florida if even the I-10 area. 

WINTER and OTHER CONCERNS?: In regard to cold temperatures, there has been no indication that any cold spell beyond One Day well into the first week of March is possible. Although it is too soon to say definitively so, we are reaching March at which time cold air intrusions seldom if ever pose a situation worth concern beyond one or two days, although cool periods can continue for quite some time to come.  

The other 'concern' will be in regard to Severe Weather. Although not necessarily for Florida, there will likely be at LEAST 3 Severe weather events to occur in the Deep South early this week through March 7th from Louisiana east and north through Mississippi/Alabama/part of Arkanasas/Tennessee and further eastward as well (other possible areas are possible in even more expansive coverage) . Whether Florida (any part of the state) will get into the 'action' is questionable, but not to completely disregard. March is often considered the "Severe Weather Month" (Severe Weather Awareness Week has already come and gone)...although the worst tornado outbreak in the State's History occurred in late February of 1998 nearly to the day.

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Friday, February 24, 2012

Very Warm/Breezy Today, Clouds/Showers Thru Mid-Week

TODAY at 3pm per RUC Forecast: Rapid Update Cycle Model forecast shows the general positioning of approaching cold front through the SE states. Note two things: 1) area of low pressure in the Bay of Campeche area extending to the north. This is evident IMPORTANTLY into the mid-levels near 5000 ft.; 2) Upper low over Mexico; this will be a factor on Sunday as it moves east and north, by picking up the MIDLEVEL portion of that low in the GULF. Colors show were storms or showers are possible over Florida today (Panhandle).

TODAY: A cold front is approaching the state, with passage through the state expected to be complete by shortly after noon time on Saturday. Meanwhile, ahead of the boundary, SW-WSW wind today much like yesterday although a bit breezier and very warm, similar to yesterday with all areas reaching the mid-and maybe upper 80Fs. Morning stratiform clouds will burn off through noon-time with a jump in temperatures after noon- 1pm all areas except toward the panhandle where clouds are more predominant and will be more extensive, and where some showers and possible strong thunderstorms could occur, although it appears most of them will be north of I-10 as of this morning's trends.

TONIGHT: Front will work down the state, possibly accompanied by a very thin band of showers and low rainfall totals due to the stretched out nature of forcing along the front. Rainfall, if any, should be less than 01.0". (one tenth inch). The front is expected to slow up a bit across North Central to Central around sunrise, then pick up momentum again after sunrise clearing Dead Central sometime after 4AM-8AM as it works toward South Central slowly.The front could be accompanied by brief showers and NNW winds, becoming possibly gusty, finally reaching the Keys and into the straights by early-mid afternoon.

SATURDAY: Call attention to the area of low pressure shown in the SW Gulf as well as the upper low shown well to the west. Those two could merge in a sense and reach across the Eastern Gulf and Florida by Sunday afternoon. In reality, our surface cold front will be very "shallow", not extending much above 3000-4000 ft, whereas at 5000 ft (850mb), the depictions show that trough aiding the surface front will hang up across Central and then lift back north on Sunday (along with that moisture with the low pressure area in the SW Gulf) as the upper low/trough translates eastward across the Deep South.

This is also for 3pm today. We can see the upper low. Note now that even though our cold front tonight and early Saturday will be south of the state, on Saturday this slow will be still well to the west and moving east. The net affect of this low will be to lift the mid-level 'frontal boundary' from Central Florida back northward with southerly winds aloft and ENE-east winds at the surface on Sunday, creating warm air over-running, extensive cloudiness, and showers across the North Half of the state nearer the 850mb "warm front".

SATURDAY (Cont'd): After frontal passage, winds will be NW-N early on, slowly veering to NE later in the day. Cloudy to mostly cloudy skies 'could' persist over the South 1/2 of the state, with a brief shot of cold air advection impacting the north 1/2 mainly. Highs in the low 60Fs, although would not be surprised to see upper 50Fs wedged in toward the Cape and north along the coast and into the interior of North Central Florida. The south 1/2 of the state will be much warmer though, possibly by 10-14 F degrees toward Miami-Dade/Keys...although clouds could be a nerve wracking persistent. Winds becoming easterly overnight with a small warming trend along the immediate coast as the come onshore across the ocean waters, accompanied by some clouds as well.

SUNDAY: Upper low well to the west now approaching along the I-10 for West Florida will tend to 'buckle' the frontal boundary at 5000 ft (850mb) which appears will never really clear Central Florida at all; hence, a shallow frontal boundary passage. As the front buckles north and the upper low moves east along and over it, so to will the area of low pressure in the SW Gulf be broken off 'piece meal' through Tuesday (at least). Abundant moisture will lift north over the state, with possible thunder SE Florida and along the West coast by later Sunday or Monday. The driving factor for precipitation / clouds will be much colder air aloft and some energy as opposed to surface based instability. Cold air not far above 'the deck' will air in mid-level lift along with isentropic lift from southerly winds above, all the while wind at the ground will be easterly becoming ESE-SE on late Monday and later on to the South toward Mid-Week before the next frontal approach.

CURRENT WATER VAPOR shows DRY air over Florida in the mid-upper levels (orange like color)..with moisture obvious by the whites. blues and greens. Note storms over Central Georgia in this moisture shot as well as SE Mississippi. The green line across Florida shows where showers seem more likely on Sunday, but the remainder of the state will become 'game' by Monday and Tuesday, if not a portion of Wednesday.. 
MONDAY-TUESDAY: Now getting further out in time, the degree of uncertainty as always becomes a big player for this time frame in regard to how, where, and why rain will fall in specific areas. Thus, to broad brush and not go into details, it remains that ample moisture will remain with a warming trend well in the mid-upper 70Fs as winds veer more toward the Southeast (SE). The mid-level 'warm front' will be well out of the picture, but the moisture will not be. Thus, expecting period of showers if not storms toward either coast on the south side of the state..showers elsewhere, but timing is near impossible to ascertain at this time. Cloud coverage looks to be a good bet though.

WEDNESDAY: Looks like a 'maybe break' in the clouds but not entirely, In fact, we do not see a drying out possible until at least next weekend. Thus, it appears all of next week will be at least cloudy if not more so. The next front may or may not even make it across the state, stay tuned.

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Thursday, February 23, 2012

Warm, Breezy, Chance of Showers (Thunder?) North Central

Note annotations: This pre-sunrise satellite image (infrared) shows few clouds this morning. Ironically, the COOLEST temperatures this morning are found over SOUTH FLORIDA, in a very stable atmosphere with weak   to calm winds in that area. Stirring of the atmosphere further north is keeping temperatures  in the upper 60Fs with a few low 70Fs north. Green and orange show where it 'could' briefly shower or even thunder after noon - 5pm.
TODAY: Low pressure crossing the Tennessee River Valley region (in general terms) will continue moving off toward the E-ENE today . Despite its far distance from Florida, the pressure gradient at the low levels associated with its distant passage combined with high pressure to the south of the state will increase the winds toward the 1-10 corridor. Upper level as well as mid-level winds remain strong, and these will be able to translate to the surface with daytime heating and colder air aloft associated with those winds to a smaller portion over direct Central. The greatest atmospheric moisture to work with today at all levels is centered across the state along I-4 toward Central as well (SR 528).

SW winds are already in place prior to sunrise, and expect that with sunshine (heating) they will increase in the 20-29mph range (in gusts) along the water ways. Coolest temperatures as a result will be found along the outer barrier islands of Brevard and Volusia down stream of this wind due to the projection of surface wind blowing across cooler waters of the rivers (which are most wide in this area). Regardless, we can still see some highs Central and South toward 78F (barriers) toward the low and maybe mid-80Fs (South Central / South interiors toward the east side of the state).

There is very little in triggering mechanisms or boundaries to set storm or shower activity off as of this morning, but instability is already in place along with very respectable bulk of speed shear between atmospheric levels. This shows up nicely on all model guidance as well as Melbourne's Local Data Integration System (LDIS). Sufficient instability and this bulk speed shear coupled with a marginal amount of directional shear (which could act as triggering mechanism in the presence of ample moisture and lift with daytime heating), could set off some showers or even thunder, closer toward I-4 in particular.  This area will need to be watched, just in case, for surprises as was noted yesterday, although none has been depicted or strongly anticipated as of this hour.


Yesterday evenings activity propagated southward even though activity was moving west to east. This propagation was likely caused by leading outflow from previous activity meeting unsettled atmospheric conditions under less cloudy sky conditions not directly downstream of upper level winds.

FRIDAY: Atmospheric moisture will be pulling out later today, thus ending the rain chance altogether. As noted yesterday, Friday appears to be the most warm day of all (especially the south half of the state). No rain chance and continued breezy, with a frontal boundary approaching the panhandle early on. This boundary, although timing remains a bit flaky, I still expect will have very little impact on the state south of I-4. Regardless, it does appear that it will cross Central near Midnight Friday night, accompanied by continued breezy WNW winds becoming N during the day Saturday. Cloudy conditions possible on Friday, especially later on in the day toward evening Central.

SATURDAY: With frontal passage over night Friday a brief course of cold air advection follows. Highs on Saturday not likely to breach the lower to mid-60Fs Central and north, warmer South. Winds becoming ENE after midnight Saturday night. Little temperature changes very close to the coast overnight, so that Sunday may dawn with a low in the lower 60Fs east of US1 many locales.

SUNDAY: Frontal boundary will be stretched out across the Florida Straits. Meanwhile, recall the upper low south of California in previous posts?  This appears still to fill as a mere trough and then be carried eastward by the jet stream winds toward and across the Southern Tier of States .  The net affect will be to lift moisture associated with the frontal boundary northward in a buckling type fashion . Thus, on Sunday it will likely become partly to mostly cloudy with a chance of some showers later in the day as this moisture lifts north and winds become E-ESE.

THROUGH TUESDAY: Shower chances and most cloudy skies at times. Location of showers is not discernible due to the fact that there is not focus or apparent triggers with great certainty. Although, a vorticity max is being indicated to cross the peninsula "somewhere" later on Monday. This all in prelude to the next typed front to enter the picture toward mid-late week. Thus, it could be a bit cloudy and a little cooler through Wednesday or Thursday with highs in the lower 70Fs and lows in the 60Fs with cloudiness over night precluding lower temperatures (acting as a blanket).    

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Wednesday, February 22, 2012

Small Rain Chance Increasing Clouds Late Today NorthCentral

300 millibar (mb) depiction from the GFS Forecast Model for 7pm this evening
Upper level low well south of California at time appears to be drifting south; this will move east later this weak as the model shows is a bit debatable, at least in regard to how much effect it will have on Florida's early weekend weather.  Otherwise,  annotated in green is where I am thinking some light rain could fall after dark toward mid-evening. Thunder 'possible' toward the Gulf Coast.

TODAY: Little to no change from the previous post of Tuesday (other than the questionable rain chance). Mid-level trough passing north of the state today from west to east with SW surface winds here around 10-15mph some locations. Warmer along the SE Florida coast, but increasing clouds further north toward Central FL should limit daytime highs to a small factor. Otherwise, satellite imagery and lightning data show a cluster of thunderstorms well out in the Gulf which appears to be heading toward the Cedar Key zone by very late afternoon. High clouds should precede this activity. Whether it holds together to the landmass after crossing the Loop Current and surrounding warmer waters is debatable, although, I'm inclined to reason that regardless, some "elevated type activity" (not surface based) could occur as shown in this depiction. At the hour, the Storm Prediction Center (the official forecasters) are out-looking the Panhandle for potentially strong storms under a "See Text" graphic,  but not indicated here in this un-0fficial blog.

Lightning is occurring in the orange box. This area appears to be spreading almost due east, thus the land areas are shown in orange for possible lightning. If this activity is indeed merely elevated 'junk-vection' it could pass entirely across the upper peninsula seeing as how it would not be contingent upon an unstable lower level atmosphere to sustain itself. There appears to be a mid and/or upper level vorticity maximum (albeit weak) that is working this activity, so perhaps that is the only 'requirement' for today's activity to manifest. This vorticity maximum (vort max) is expected to cross the state near Ocala toward Gainesville after dark but before midnight...

THURSDAY/FRIDAY NIGHT: Other than today's system of 'sorts', a prolific subtropical jet (see first image) is in place across the southern tier of states in a developing zonal flow of quick moving spurts of energy. Wind each day from the SW-WSW and warmer on Thursday and Friday (especially), when cloud coverage might be less extensive over much of the peninsula. Highs in the mid-upper 70Fs and some near 80F+ south today, but more so over a broader expanse Thursday and Friday. Might see some near records highs on Friday South Half of state as the next front moves in. Front enters Central after dark Friday.

SATURDAY/SUNDAY: Front is expected to stretch on in from the N-NNW-NW after dark Friday evening preceded by increasing clouds once again and a small to fractional rain chance through midnight before stretching thin and beyond its mean. Do note, that any rain from this boundary appears will be BEHIND the front rather than ahead and along it. This front will be associated with the low pressure system now well south of California noted in the first image above with movement indicated by the arrow in red which will follow a due course similar to the current winds also shown (in yellow). 

With increased clouds and some 'warm air over running' in place behind the cool and shallow air mass, Saturday could be a bit cloudy and cool as winds shift from NNW-NNE during the course of the day while winds just 5000 ft and above remaining from the west. Hence, this will be a 'shallow front' (not extend far up into the atmosphere)..and not long to last. In fact, by Sunday the wind will already be back from the east by day's end.

BEYOND: Next front is forecast to enter the picture in 3-4 days along the zonal flow pattern toward Tuesday/Wednesday . The trend has been for some time to indicate that the jet stream as shown in the first image will be lifting even further north, making for weak fro-pas (frontal passages), but perhaps prolonged periods of clouds as they struggle to squiggle clean of the area, leaving residual atmospheric moisture as their calling and goodbye cards.

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Tuesday, February 21, 2012

Warming through Friday, Possibly More Unsettled Beyond

Latest Enhanced Water Vapor Image Shows Moisture in the Mid-Upper Levels of the Atmosphere Only. From this image, and equally so when animated, it is apparent that a bit of a modified "Pine-Apple Express" type pattern, typical of a La Nina period , is resulting in high level moisture flowing in a stream overhead North Florida from the Pacific region. The area most impacted by this moisture will likely shift a bit south toward Wednesday as a system passes to the north of the state; however, increased convergence aloft and at lower levels could bring moisture up at any level, thus resulting in period of possibly cloudy sky conditions on Wednesday, and at any time later today toward late afternoon North and Central regions. 

TODAY: Light wind from an east to southeast component becoming calm, most notable right on the beach where cool ocean waters will affect the air temperature. Otherwise, highs in the mid-upper 70Fs. We can see that latest trend in temperatures as noted at 1pm per the Local Data Integration System feed accessible from the National Weather Service Office in Melbourne, Florida. Wind to become south to SSW-SW by sunrise on Wednesday. The land breeze will allow overnight lows to fall into the mid-50Fs many areas, but quickly warm upon one hour after sunrise.

WEDNESDAY: Expecting more clouds as a mid level trough passes to the north of the state. Although showers do not appear possible, the increasing chance of clouds at most any level in the atmosphere should temper afternoon high temperatures into the mid-upper 70Fs west of any body of water, and a bit but not significantly so cooler east of bodies of water (Barrier islands).

THURSDAY/FRIDAY: Again, land breeze over night with continued periods of cloudiness varying from partly cloudy toward cloudy, most notably after 3-4pm when the lower sun angle requires the rays to pass through more clouds. Highs approaching 80F to lower 80Fs (South and parts of interior) are possible, but mid-upper 70Fs most likely everywhere regardless all of Central and South, and generally south of I-10. A cold front as shown in the first image now working into the Inter-mountain West , and its associated upper level trough, have consistently appeared to be a harbinger of a pattern shift (later on this).

The models (the GFS namely), has been latching on to this change, although the degree to exactly how much of a change is warranted for the curious minded remains a bit fuzzy. The Pineapple Express type flow can last, historically, anywhere from nearly a week to several weeks.

SATURDAY: GFS run to run consensus indicates the front proper will be working into Florida either late Friday or very early Saturday, but will have cleared Central before mid-morning Saturday at the latest. This could change. GFS temperature fields indicate a similar very cool for a day regime as with the previous frontal boundary. Namely, nothing outrageously cold nor long lasting although it could be quite cool and breezy to near windy on Saturday, and continued cool on Sunday.

BEYOND: As noted, the system impacting Florida's weather beginning Friday and through the weekend could be a change in pattern. The GFS has bounced around with bringing better rain chances to the state beginning some time around late Tuesday into Wednesday ofo next weekend and lasting for several days (up to 5) as the next front moves across the state, gets hung up 'somewhere across the peninsula', then eventually lifts back out to the north and pulls away to the east. This would be a welcome respite in regard to the dry conditions over the state. As it stands, this is the normally driest time of year, and so far this season we are drier than the dry norm. This does not bode well for the "Fire Season", as was a threat last year (and every year). There has already been an account of a fire yesterday of notable proportions.  

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Monday, February 20, 2012

Pleasantly Cool Today, Warming Through Late Week

Cold front (shown in blue) cleared state over-night. Red arrows indicate jet stream level winds (Above 25, 000 ft in general). Light Blue shows mid-late afternoon wind coming off very cool Atlantic Ocean waters to impact coast as far south as the Outer Barrier Island of Brevard (A1A). The closer to the dunes, the cooler. A few high clouds could pass over anytime, most notably toward late afternoon/dusk.

TODAY: On track with previous post, mornings lows are mostly in the mid-50Fs to near 60F+ (South Central and South), with near 70F Keys. Otherwise, as can be seen, the cold front has cleared the state. Jet stream level winds will be in play all week through and into the weekend, for which case, we can easily speculate that some increased high level clouds working overhead at anytime are possible...but timing as to when is as good as written on water, an open book. Otherwise, winds from the NW this morning will gradually veer toward the north late morning and then NNE-NE later today. With cold ocean waters at bay, the immediate A1A corridor will likely and most notably receive the full impact of the cool winds as far south as Eau Gallie Causeway or Melbourne Causeway, specifically from Cape Canaveral and north. Otherwise cooler the entire north portion of the state from near I-4 and north. Light winds.

TUESDAY: Winds overnight will continue to veer to easterly and southeasterly overnight tonight and on Tuesday. As such, overnight lows inland will be allowed to fall under the normal diurnal cycle, but immediate coastal temperatures will remain in the lower 60Fs, so a fair trade works in on that regard in the temperature fields. Tomorrow's highs should reach into the lower-mid 70Fs many areas, with again the immediate coasts being the coolest, specifically from Canaveral and north.

WEDNESDAY-THURSDAY: Cool all locations (50Fs) early morning most areas Central and North as winds become Southwest (cool morning land-breeze); on the other hand, warmer in the afternoons through Friday or even Saturday.

The next front is forecast sometime in the Saturday time frame early on, but timing will likely be an issue as will rain chances. Best gander guestimate in the forecast realm is that despite the models showing rain chances, suspect those will dwindle down to only being noteworthy north of I-4 if not even further north than that.  Watching though in any case for late week forecasts . 

This is the going trend heading into the first week of March, but hold tight, it gets very fishy toward the entire first week of that month. Sketching traces in the sand, and waiting for the tide to wash them away on any wave is the course at this point, so not to build the sandcastles on baseless uncertainty.

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Sunday, February 19, 2012

Breezy Today, Showers *Thunder? Possible Mid-Late Afternoon

GFS Forecast for 4pm EST today, showing approximate hand-plotted front positions
Note the dark shades of blue and wind barbs , 20-25 kts of wind equates to winds today in the gusty range toward  25-29mph. Possibly higher near approaching and in any showers or thunder

TODAY: A cold front is entering the Florida Panhandle well before sunrise and will continue through the state, exiting the southern extent in the early-mid evening hours. As of latest guidance and actual radar/satellite trends, it appears that the main wind energy will be restricted to the north half of the state, whereas any thermal instability (also required for respectable storms) will remain over the south half of the state.  In that regards, they do not combine (or overlap) into a 'neat little package' for assured storm generation.

This wind energy even so will be unidirectional throughout the layers of the atmosphere  (from the same direction as opposed to veering with height) which does not bode for rotating storms. Additionally, due to the unidirectional (from the same general direction) wind profiles as one goes higher up in the atmosphere from ground level, there will be little 'forcing' or converging of winds at the lower levels required for forced upward motion into higher levels of the atmosphere (squeezing). Without forcing, thunderstorms might be hard to come by. Also of note, the 500mb vorticity (wind energy) field indicates near NEGATIVE vorticity, which actually plays against storm formation.

With this line of 'reasoning', I'd expect that thunderstorms will be few and far between, limited mainly toward the Tampa Area (not shown)..with perhaps some rumbles within the area of green shown in the above image. 

Increased cloudiness by early afternoon ahead of and along the front will work down the state. Additionally, due to the stronger wind aloft (and cold air), those winds could translate to the surface resulting in breezy conditions today. Highs will be unusual, with near 80F + from South Central to South Florida where cloud coverage will be later to arrive (during peak heating). Dead Central could approach 80F though, especially along the east half of Central.  Increasing clouds and a period roughly from between 2pm - 5pm of light fast moving showers or even some rumbles is possible, extending about as far south as the north shores of Lake Okeechobee toward late afternoon or early evening, all contingent upon the forward motion (timing) of the boundary itself. It is possible that daytime heating will slow down the motion of the boundary, in which case we can tack on up to 2 hours of the shower timing. Given the current upper level trough (system) to the north of the state though, this does not to be a likely or significantly problematic concern.

Do note,  however, that as of this hour the Storm Prediction Center (SPC) located in Norman, Oklahoma has a 'slight risk for severe' as well as a 'see text' in place for the area in green as well. "See Text" essentially is reserved for 'we are watching this area for stronger storms not meeting severe criteria'. Those areas, as it appears, are highly conditional upon formation of storms in the first place. Best chance for thunder might very well be over the Gulf Stream waters and also moving in off the Gulf as far south as Sarasota, but whether any can hold together across interior is the big TBD. 

Any band of showers / the front as it may be, will continue southward into early evening with clearing skies to some degree before dark (Central)..but not entirely so until mid-late evening. Not all areas will see rain today, in fact, most might not.

Temperatures will not fall dramatically behind the boundary (Central/South) as winds become westerly then WNW into the evening, and not really be an issue until after midnight. Lows by Monday morning close to the low-mid 50Fs immediate east coast from the Cape and South Florida, with upper 40Fs to lower 50Fs interior and north with a breezy NW component to the wind early on.

LATER MONDAY: Winds become lighter by late morning through afternoon and veer from NNW-NE-E (by dark)...with near clear skies with highs close to the upper 60Fs right at the beaches (Central), but a bit warmer inland away from the very cool ocean water. Highs over South Florida into the lower 70Fs (at least) most areas. Some clouds might very well work into the east coast and inland by early-mid afternoon as winds turn more easterly.

TUESDAY: Southeast winds and warmer still through Wednesday or Thursday before another front approaches. This front too as it appears will have little impact (if not less) than today's. Another front is then again forecast beyond that time toward next weekend..impact hard to determine at this point (if any).    

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Friday, February 17, 2012

Considerable Cloudiness Today, Possible Showers Central Later

Morning satellite image indicates clouds at various atmospheric levels passing from west to east when animated. There are some patches of light rain within the clouds, mostly north of I-4 and heavier activity well west into the Gulf of Mexico. Some of this activity could impact Central Florida later today in mid-evening as the surface cold front looses identity and sinks south toward at least Southern Brevard, although it is possible it will not get quite that far south. Heaviest activity (if any) should be restricted to Central proper especially after 2-3pm.

TODAY: Very little change in reasoning from yesterday's post first and foremost. Frontal boundary across far north Florida is being elongated from east to west as the parent low pressure area moves off well to the north near Nova Scotia, with little 'forcing' along the boundary way south of that low in Florida.  The frontal boundary will sink into Central Florida later today.The exact location should not hold much weight either way as far as how its southern extent penetrates, although showers are most likely where-ever it tends to halt any further southward progression. For the most part, there has been little change in reasoning with the GFS model continuing to take the boundary as far south as Southern Brevard if not a bit further after sunset tonight. With that, it would not be unreasonable to expect that some rain could fall across Central Florida from mid-afternoon through late evening, especially Central heading toward early evening. Some thunder is 'possible' but doubtful.

Light green shows area for best rain chance. Note that the front extends in this depiction from low pressure near Nova Scotia with a new low forming along the tail end along the Texas Gulf Coast. It is that low pressure and the attendant cold front that could make for more active weather on Sunday

SATURDAY: The new area of low pressure moves toward North Georgia with breezier conditions materializing by mid-afternoon. It appears clouds will still be present with sufficient moisture, but no rain due to no triggering mechanisms, other than perhaps a few light sprinkles. Winds begin to increase over night as the front draws closer. The front across Florida lifts north and becomes a warm front well north of the state.

SUNDAY: Cold front now crossing the state. Winds from the SW at 20mph at least, clouds, and some showers and possible thunderstorms (potentially close to severe due to strong winds) will move through from early day through sunset, crossing Central Florida during the mid-afternoon toward late day. It is during that passage the better chance for stronger storms is possible. It will not be an all out rainy day by any means as noted yesterday due to the rather fast forward motion of the system. I've drawn in a quick and dirty version of where there is a potential (for purposes only of this unofficial blog) of where the stronger activity could occur (this is not a given, for awareness purposes only).
Orange, possible thunder ; Red, possible stronger / severe storms due to wind , fast moving 

LATE SUNDAY: The front and associated rainfall potential will have cleared Central Florida before sunset and will have cleared the state by mid-late evening on Sunday. Winds then become NW and filter in cooler/colder , drier air.

MONDAY: NNW-N winds as morning works into early afternoon, becoming NNE-NE by early evening. Morning lows at the coast 46-52F and colder inland and north. The entire state will be effected by this cold 'shot', but as noted previously..this one will not be for long. In fact, by Tuesday morning the temperature at the beaches could be warmer than they will be at  10pm the previous evening (Sunday Night) from Cape Canaveral and south.

BEYOND: Not significant weather of note heading through mid-week. 

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Thursday, February 16, 2012

Rain, Storms (Strong/Severe) Possible Friday & Sunday Florida

NOW: Frontal boundary sliding into the Panhandle Resulting in Greater Cloud Coverage in North Florida North of the I-4.
Later today, East Coast sea breeze with increased atmospheric moisture could result in some sprinkles or a shower due to sea breeze convergence away from the coast, inland. Colder ocean temperatures should essentially 'cut off' or preclude any shower activity closer to the coast due to loss of rising air currents above and near the cool ocean and river waters

TODAY: Two cold front boundaries will be playing havoc with the Florida Peninsula weather forecasts through Sunday beginning today. Although today does not appear 'sticky' regarding significant weather (especially South of the Beach Line), the main factor within this same area (North Half of State) looks to be the variability of cloud coverage with a better rain chance north of I-4. As noted in the caption , sea breeze convergence or simply a sea breeze and weak inland winds could result in weak convergence (surface to mid-levels) resulting in some sprinkles which looks only minimally possible if at all namely due to the cool waters and the cool air just above them cutting off the lifting currents normally present in the summer months when waters are much warmer. 

FRIDAY: The cold front will get an extra boost southward after wafting toward the east, with the main energy being pulled well north and east of the state. Regardless, the front should be entering North Central (Ocala / Gainesville) area during the noon time hours and finally reaching Central Beach Line Corridor toward Tampa by late afternoon during and after peak heating hours. Wind fields do not look overly impressive; albeit, if this was the summer with the same wind fields this would be a day to watch for very strong thunderstorms no-doubt. Regardless, given the wind fields and ample instability, there could easily be a thunderstorm chance with good winds in them from northern parts of South Central and Northward. As we can see here:

NOTE the winds are shown at the surface to be only around 10 knots, but convergence along the frontal boundary will work in favor of storms along it and south. This is the GFS depiction from the morning model run (7AM), valid for 1pm Friday. This front is expected to make it about as far as Ft. Pierce toward Sarasota before lifting back northward as a warm front overnight Friday night into Saturday.  Therefore, it would be wise to be prepared for rain when heading out across Dead Central beyond the 2pm time frame through at least mid-evening. The front appears will stall out across a portion of Central before lifting back north. During the time, rain chances will remain.

SATURDAY: More interesting chain-of-events unfolds. First time in months since we've seen a scenario such as this. In fact, outside of the tropically related entities of fall, it was possibly last April or May that such a boundary could generate severe weather in a broad scale, or have that inkling, over a part of Florida. Thus, this will be a day to keep the ears and eyes pealed for statements and newscasts.

The cold front of old will lift northward as a warm front (as shown below), with an attendant low pressure system pulling eastward north of the state. A new cold front will be entering the picture with much stronger wind fields associated  at ALL LEVELS OF THE ATMOSPHERE.

Given directional wind shear in a clockwise fashion from the ground and up toward 30,000 ft (climbing upward through the veering wind fields with height), there will be a best chance for severe storms and possibly a tornado from near St. Augustine as far south as Ormond Beach (at least) and west across the state. This entire scenario is still 'in the making' as far as being depicted on paper is concerned, so most assuredly this portion of the post will need further refinement in the next 36-48 hours as time allows. Here is the morning depiction for 7AM Sunday morning.


NOTE the stronger wind fields even at the ground (as shown) as opposed to Friday. Blues show winds in the 25 kts range over water, as opposed to 10 kts on Friday. No joke, winds aloft are much stronger
on Sunday than they will be on Friday as well.
Also note the text in red showing that the old cold front has lifted well to the north as the next low pressure (much stronger this time) moves across the Deep South. Undoubtedly, our friends on The Weather Channel will be milking this one for whatever it will be worth in the severe weather mode realm across Dixie and into the Carolina's at least, as well as parts of North Florida from early Saturday through Sunday. Especially over portion of Alabama and Mississippi!!

Since it is yet early for finer details, it is worth watching for a fast moving squall line type feature to race across most of the peninsula from mid-morning through late afternoon. Precipitation totals are not shown to be high, but bear in mind it will be fast moving which correlates to little time for rainfall totals to add up. Meaning, not much rain does not directly mean some stronger winds will not be briefly possible.

Regardless, that does not mean, nor should we assume, that strong winds (at least) will not be possible, especially North of Lake Okeechobee mainly, not to play any 'favors' just yet in regard to who might escape the rains. As seen today at this point from scanning over a few resouces, most everyone could get a quick dose of rain and wind on Sunday from before sunrise (far north) to the keys by late afternoon/early evening.

BEYOND: It will be much cooler Monday morning behind the front, but not as cold as this prior event. Winds are expected to clock around toward the NE to east within 36-48 hours after frontal passage which means already any cold air supply will be tainted by Atlantic winds. Additionally, the jet stream will be north of the entire state. That is important to Florida since the coldest temperature at ground level in most cases is found under and north of it's flow and ebb around the hemispheres.

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Friday, February 10, 2012

Be Fore-warned Florida...It's Gonna Be Cold in These Thar Hills

Coldest Full Day (or nearly so) of Winter for Florida is in the Making, but first comes some rain

A different flavor of post today, no maps required. The writing has been on the walls for nearly two weeks now (I have been watching behind the scenes), that a change was in the making as noted in the previous two posts. It now appears that all will come to fruition. Earlier posts were not definitive since it is not particularly beneficial most of the time to put the cart before the horse (the boy who cried wolf syndrome as weather folks are so famous for). I suppose it is time to cry , "Man Your Battle Stations!...Cold air is on the way."  And it looks like a doozy. But all is not as bad as it may seem. Meaning, this does not appear to be a long spell of it. However, even more changes are a brewin', at least in regard to implications made by the weather models. Again, though, this seemed to be also in the making. With this in mind....

TODAY: A cold front is in development and to cross the state through the day and into the evening and overnight. Ahead of the front, clouds will persist for the most part as winds begin to shift from southeast to south and eventually Southwest. There is a chance of thunder after 2-7pm considering : (1) the respectable amount of bulk wind shear throughout all atmospheric levels in what is referred to as the boundary layer  and (2) atmospheric instability (which is not all so impressive to say the least) does exist today as opposed to previous frontal passages.

Prior to that time and during it as well, some lighter rain may fall, particularly over the southern 1/3 of the state initially. As the front approaches toward mid-afternoon rain chances and possible thunder from near Canaveral and South, where as other showers and maybe thunder further north along this developing two-tonged system moves through could occur, although thunder along the front itself appears less likely. Without going into meteorological specifics, there is agreement in models to a respectable degree...and the National Weather Service has taken a bite as well along this line of thinking. 

SATURDAY: The overall system which is much larger than what is impacting Florida will be moving east of the state as NW winds filter in during the day after the frontal passage which appears will occur shortly before mid-evening through post midnight across the peninsula. Thus, on Saturday..the air will begin to dry out from the dank and damp conditions of recent days (in the evenings)...and with drier air comes colder air, since dry air holds less heat over the night time hours. The second phase of this system will clear all of the northern 2/3 of the state by mid-Saturday evening as temperatures fall into the 40Fs and the air outside continues to dry.

SUNDAY: Potentially the coldest day of the winter 2011-2012 season from sunrise to set. Highs possibly never to clear the upper 40Fs (but see further down too) most areas at and north of Lake Okeechobee. Morning lows toward freezing from I-4 and north, if not even further south than there. Coastal east coast lows in the upper 30Fs toward low 40Fs. The difference in this cold spell as opposed to the previous will not be so much the morning low, but rather the lack of warmth Sunday afternoon with continued winds to abate not enough for uncomfortable wind chills until Monday early.

This image is a forecast from the Global Forecast System (GFS) model showing in blue 30F's if not colder toward far Florida. The green tones are noted first with the 40F print. One can take it from there. Afternoon highs to make it into the low 50Fs central toward South Central and warmer yet further south based on this run, but we will need to watch those numbers. Could be yet colder than shown here.

MONDAY: With the worst over, and winds becoming more easterly..the immediate beaches from Canaveral South will likely be in the mid-upper 40Fs, with continued cold (but not freezing) elsewhere on more morning...Monday will be a few or more degrees warmer all locales, but still chilly by comparison to days like those of yesterday and today.

TUESDAY/WEDNESDAY: Continued warming toward the 70Fs with a rapid warm up over nights as well. This is not the end of the saga however as alluded to in the opening paragraph. Although very cold air is not yet depicted, the chances for rainfall and possible storms remains to be  an emerging possibility once again. As usual and  would expect from a blog named "High Speed Dirt", the watch for active severe weather will need to be considered heading into the later parts of February for somewhere in the state.

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Saturday, February 4, 2012

Stream of Weather Consciousness = Changes

The weather here on the earth's surface has many dimensions. The winds, the sun, and gravity dictate much  of what we experience coupled with the rotation, sun angle relative to the earths orbit, and pre-existing conditions of the past all add up to the present experience. Like our lives, the sum total of our past experiences and all those encompass manifest as the Now. Such as is the case with today's weather on February 4th all around the globe. The stream bed, the twigs, the rocks, the blocks where twigs and branches get stuck, and various depths of the waters combined dictate the birth of what will finally emerge as we see and experience it at any point in time anywhere , anyplace,....... as weather.

TODAY-MONDAY: High pressure is moving east of the state of Florida as well as to the north just a bit will drop  south in the next 48 hours as a cold front approaches. As such, winds will become easterly to southeasterly toward south into Sunday late...which will also result in an increase in atmospheric moisture. Although there will be little change in temperatures, with daytime highs coolest along the east coast due to the cool ocean waters this time of year..a chance of rain will formulate with this increase in moisture especially on Sunday afternoon through at least early Monday. At time, not expecting thunder due to the indication that upper level winds and thermal dynamics (thermodynamics) will not be sufficient to generate more volatile type weather.   Thus, showers are quite possible for much of the state, especially east central to south Florida on Sunday afternoon toward at least mid-morning Monday with partly cloudy to sometime cloudy skies possible. Otherwise, very un-winter like all things considered.

BEYOND MONDAY: The front appears will slip slowly south and then east of the state heading through Tuesday and beyond with little overall changes indicated beyond that of which has been the current state of affairs. However, there are hints of changes awaiting on the wings of noted in the previous dialog a while back...there are signals..that a chain reaction of events could harbor a change...potentially a bit volatile in nature..

LATER NEXT WEEK: Beyond this front to pass through in some sort of oblique fashion early week...the GFS long range assumption has been progressively and continuously pumping out a picture indicating that low pressure systems could form close to if not in the Gulf of Mexico. Such systems bring more dynamic wind fields, instability, and low level 'boundaries' resulting in storms and rain. Although no cold air beyond the norm is shown, it does show that rain will much more likely occur toward later next week ..thunder possible. Even this will have to be watched, especially Central and South Florida for a mini-severe weather chance heading toward the Ninth of February...but no guarantees.

BEYOND THEN: More of the change continues. Like a domino affect, the effect around the Northern Hemisphere occurs in all places, coupled with waves of change in the Southern Hemisphere...a chance of a severe weather outbreak could occur toward mid-February somewhere in the Deep South toward Florida. At this time, it is too far out in the great beyond to get down to specifics as to when and where or even If...but the overall indicators point for this 'new change' of changes to potentially remain in place. The low down and dirty is, we have had benign weather for a while..the bump is appearing to no longer remain on the log.

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