"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".

Thursday, January 26, 2012

Heads Up Florida! Chance of Storms, Possibly Severe on Friday

Frontal boundary is clearly evident crossing into the Florida Panhandle this mid-afternoon
Thursday per this image. The Front will be slowing down tonight, with a secondary shove to the southeast beginning pre-dawn Friday and reaching near south Florida toward sunset Friday.

TODAY: Breezy SE winds over much of the peninsula except closer to the frontal boundary which is on the approach from the WNW-NW. The front can be seen in the above satellite  image extending well south into Gulf of Mexico northward toward Crestview and Geneva. Conditions   over the peninsula will remain overnight warmer than usual  due to winds remaining elevated and some cloud cover enhanced by increasing   atmospheric moisture (precipitable water) throughout the atmospheric layers. Lows tonight likely to remain in the 60Fs closer toward 70F South Florida.

Winds also becoming S-SW overnight with a SW and slightly breezy sunrise speed in the 10-18mph range. Increasing clouds as showers and possible storms move into the Big Bend to JAX areas in the pre-dawn toward early morning post-sunrise time frame. 

FRIDAY: The front will be slowing down toward later today and tonight as its upper level supporting low pressure complex lifts more toward the NE, stretching out the boundary and slowing its eastward progress.

Upper level jet stream winds will maintain strongest, primarily across only the far North Portion of the state; yet, a secondary jet streak will develop across Central Florida  as the upper trough begins to lift ENE-NE tonight. The region very close to Dead Central Florida per latest GFS and NAM forecast models indicates that the area drawn in red will be under the exiting left region of this jet streak. Additionally, due to the timing of this system as laid out in model guidance (The NAM and GFS have finally come to a timing agreement in the 18z runs! ..for the first time since showing the system's approach)..Dead Central may have a more primed environmental, conditional impact for strong storms since this boundary will be approach that area of the state during peak heating of the day, although any destabilizing heat will be likely offset by high cloud coverage to some degree.

Light blue frontal position estimate at 10AM Friday morning. The orange and red are also first wags and storm threats (orange, general thunder with stronger wind gust and RED: tiny severe weather threat).

Concerning the upper level winds: Winds  will be largely uni-directional with height, but not entirely by any means. Additionally, any stalling could tend toward greater directional shear depending on how far northward the upper level trough lifts out. Regardless, speed shear and bulk shear both could provide the impetus  for showers and storms to create wind gusts or straight line winds in the 35-50mph, with a gust or so approaching severe category, namely at or above 58 mph. As of this time, the Storm Prediction Center based in Norman Oklahoma is watching this system for Florida impacts as I write this post. At time, the peninsula is being out-looked under a "See Text" banner, with hardly a reference to bona-fide severe weather threat, YET. They are watching  for a better signal to sound the horn.

 In that regard, and based on what I personally am seeing in the model and for purposes of this unofficial information, have included a "severe chance" in between the areas in RED in the first graphic above.

Thunderstorm chances will occur between sunrise (Far NW) to Central working south and east from mid-morning through early afternoon as the particular set up for storms works further south. By mid afternoon, the upper level supporting winds for stronger storms will be pulling out, so expecting that there will little left but a line of showers with some thunder south of the orange most southern line in the above image.

BEYOND: No so bad  in the temperatures as feared previously. Overnight lows will indicate little change Saturday and Sunday from recent days, but cooler afternoon highs a possibility. Although, given what this winter has been like so far, no special preparations with lows in the upper 50Fs to near 6oF Cape Canaveral and South along the IMMEDIATE coast..cooler inland, with lows in the 40Fs north of I-4. 

The colder morning will be, as it stands now, on Monday when a second boundary will have pulled through dry, but swing winds back toward NW..making for a much cooler morning Monday morning. That morning will be followed by a fairly rapid swing to onshore wind component..and we can call it a day with cold air threats.

NEXT SYSTEM: Having been watching and watching and watching, there appears to be indications that a more widespread chance of rain and maybe storms will be once again knocking on Florida's Door come close to this very time next week when rain again will be possible. This next system has been in the cue on the GFS model for quite some time, but given the time extension until we reach reality..anything yet can go.

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Wednesday, January 18, 2012

"Cold Front" Sliding Slowly Through Florida Today - Not a Big Change Maker

9AM Position of cold front with moderate rain showers and some thunder over the Gulf of Mexico
The front to slide into Central Florida mid-late afternoon through midnight (South Central by then).
SMALL chance of elevated thunder as show in the image, but minimal. If so, even a heavier rain shower if possible could manifest a wind gust or so in the 40mph range, but again, chances are low but not completely unattainable for thunderstorms. 
Here is how the same area appears on satellite imagery. Note how long the front will take to get into Dead Central today. In other instances of cold frontal passage, the distance to be traversed  with strong fronts could take a matter of a few hours rather than 12 hours at least as will be the case today.

And Finally........

Wind fields MSLP (Mean Sea Level Pressure/The Surface/Ground Level). SW-WSW wind today and warm most areas except North Florida before cloud cover moves in. No problems for peak heating all of Central and South..but far North Central might get the clouds in before peak heating  north of I-4. Note the  projected cold front positions, and how it barely skits by far South Florida before pulling off more toward the east rather than south. Rain showers or a sprinkle possible between the green lines.

TODAY: It is Wednesday, January 18. Cold front moving South and East today through Florida with warmer temperatures most areas except the barrier islands of Brevard downwind of the cooler waters of the Two Big Rivers but even there it will be warmer today (just not 'as warm' as inland); highs even still will be in the mid-upper 70Fs and maybe some lower 80Fs South Florida toward the East Side of the state. The front is accompanied by cloud cover expected to reach I-4 and south during early-mid afternoon in varying degrees, reaching Dead Central toward late afternoon.

If there is to be any thunder heard today suspect it will be up until 9pm toward East Central, but lightning even then SHOULD be either cloud to cloud or in-cloud (and not hitting the ground). There is a sliver of opportunity in there for cloud to ground strikes along and just north/south of I-4 as far south as an area near Sanford/Mims until 7pm. Any showers or even a thunder producing 'storm' especially could result in wind gusts around 40mph. ..

HOWEVER, this discussion is based on 2AM EST forecast model runs, thus early morning information has not been assimilated yet into the model depicted outlooks which will be spewing out of the computers shortly after noon time. Thus, refinement if necessary, of this post could be necessary by early afternoon. Anticipating that if anything, conditions will not be even as 'bad' as written in this post. Better case scenario will be very little rain anywhere south of I-4 except toward the East Side of the State. Rain is not expected as far as this blog post is concerned south of a line running from Palm Bay to Sarasota, and most of the official NWS offices seem to be in agreement on that from what I briefly read this morning.  

I did look at the morning Storm Prediction Center (SPC) which is located in Norman, Oklahoma, Outlook for thunderstorms today..and this is their line of thinking for POSSIBLE thunder, not definite thunder.

The "Storm Prediction Center" (SPC) Thunderstorm Outlook for today issued around 8AM EST this morning. Note that no Severe Storms are anticipated per the other colors indicating "Risk" of Severe Levels Ranging from Slight to High Risk of Severe

BEHIND THE FRONT ON THURSDAY: Cooler temperatures for a day or so after the front the north half of the state, or another way of looking at that same area in green above where thunder is possible today. The warmest morning lows will run down the Barriers of Brevard toward Palm Beach County and across toward Sarasota and South as winds will quickly swing around to NE-ENE-E during the day on Thursday and then become more SE on Friday. Mornign lows in the mid-upper 40Fs interior Central and North, but along the Barriers and South in the mid-upper 50Fs ..much like those of yesterday and today.

WEEKEND THROUGH MONDAY: Warm! Overnight lows along the east coast from the Cape and South possibly in the mid-upper 60Fs by Sunday morning if not 70F and daytime highs in the mid-upper 70Fs near the beach and into the low 80Fs by Sunday inland. No real chance of rain is in the extended, nor is any cold air through the remainder of January anticipated. As noted before, that last cold spell could have been our last of longer than 1 or 2 day duration for the winter. Still have the first 1/2 of February to go though. Severe weather chances will need to be looked out for as well as we approach Florida's severe weather month (officially) of March, although, with the La Nina Pattern in full-hold, even that might be dealt with in ease.   

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Sunday, January 15, 2012

"Sundog" in Center of Image formed by ice crystal in the high altitude cirrus clouds
Sundogs are made commonly of plate-shaped hexagonal ice crystals in high and cold cirrus clouds or, during very cold weather, by ice crystals called diamond dust drifting in the air at low levels. These crystals act as prisms, bending the light rays passing through them with a minimum deflection of 22°. If the crystals are randomly oriented, a complete ring around the sun is seen — a halo. But often, as the crystals sink through the air they become vertically aligned, so sunlight is refracted horizontally — in this case, sundogs are seen.

TODAY: Based on latest satellite imagery and a throw in from model guidance for comparison, high clouds today will be  less prevalent than of yesterday.  That means in a nut shell, more sun than not. Winds from the NNW-N later in the day at 10-18mph along the open areas with highs in the low-mid 60Fs, and some upper 60Fs South Florida.

TONIGHT/MONDAY: Winds becoming light after or near dark and veering toward the NNE-NE-ENE through the overnight. Coastal lows from Canaveral and south should level off mid-late evening in the mid-upper 50Fs, whereas further from the coast lows will fall within the 40Fs realm with only a few high clouds.

On Monday the wind will become ENE-E during the day with highs all areas in the mid-upper 60Fs, possibly lower 70Fs SW Coast of the peninsula. Clouds becoming a non-issue in the high altitude level category, but a better chance of lower level clouds due to moisture off of the Atlantic. Monday overnight lows again warmer than the previous evening, remaining in the low-mid 60Fs Canaveral and South, 50Fs inland or upper 40Fs. Winds continuing to veer toward the ESE through SSE toward sunset.

TUESDAY: Winds overnight will be  veering yet more toward the S-SSW-SW. A cold front will be entering our 'picture' but have little to no impact Central and South Florida in days ahead. Circulation around high pressure near Bermuda continues warm air advection with highs all areas in the mid-upper 70Fs with partly cloudy skies with a small chance of mostly cloudy intervals. In short, nothing like the past few days have been by a long-shot.

WEDNESDAY: Cold front will be struggling to impinge through the peninsula with noteworthy impact. Any rain showers should  be restricted to the I-4 corridor (Tampa/Orlando/Daytona) ie. North Central and north, although a sprinkle or light rainshower 'could' occur Central Wednesday evening toward sunrise Thursday. Mostly cloudy and a pleasant overnight low in the 60Fs.

THURSDAY/SATURDAY: Winds behind the front as it undergoes frontalysis quickly become ENE-E behind its decaying boundary pulling east and out over South Central Florida never really reaching far South Florida. Lows remaining in the 60Fs east coast overnight with highs in the mid 70Fs interior, but cooler east of US1 due to the influence of cool ocean waters and light onshore winds.

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Friday, January 13, 2012

Florida Front Frolics Forth and Through

Infrared Satellite image shows front's position around 730AM south end of Lake
Okeechobee, after clearing Central around 6AM. Red shows in general the jet stream level winds today through most of the weekend and thin patches of high clouds associated with those winds. Another image further down shows those winds in graphic form.

Colorized Depiction with labels of surface temperature in Fahrenheit Degrees at 730AM EST. The 60F line HAD been north of Dead Central prior to the front early, early this morning. Blue arrows show direction of colder air impingement southward.

TODAY: Best surprise is no surprise in the case of today. That being, the cold front went through per schedule and is now toward the south end of Lake Okeechobee one hour after sunrise. Much drier air is located over North Florida with dew point temperatures in the upper teens to mid 20Fs. In comparison, the Daytona Area has dewpoints now in the mid-upper 30Fs and East Central toward Canaveral remains a good 10-15 degrees higher. The dew points  are a good determinant of how dry the air is. The lower the dewpoint the drier the air. The dry air is working south all day along with the colder air (drier air holds less heat).

Highs today will likely not get above 60F north of a line running through Melbourne or Palm Bay area toward South Tampa Bay...with highs near the lower 70Fs far South Florida. Highs in the lower 50Fs North Florida. NW wind all day at 10-15mph.  This cold spell in a sense will not be as bad as the previous one for two reasons. 

1) It looks like we will start out with less brisk of a wind thus wind chill temperatures not a big player; and, 

2) All in all over night lows not looking to get toward freezing on any overnight period. 

This will simply be a bit of a prolonged very cool to cold period with intermittent cloudier periods, especially over the Southern 1/2 to 1/3 of the state through the weekend. Thus, although it might be cooler further north (North Central and North), this area is more likely to see more of the sun and feel direct warmth from it's rays as opposed to those in South Florida. Give or take which ever one prefers. 

Today and Saturday Jet Stream Winds forecast with front location mid- morning today drawn in. This shows the air mass moving over Florida will be a bit of a modified Pacific NW type and not straight from the North Pole as is the case when there is a widespread freeze over the state. This also shows how Pacific type winds are playing in to the equation, aiding in the modification of the' air mass', although this depiction is for generally 30,000 ft aloft (6 miles over head), as opposed to at the ground.

Note the wind speeds annotated in the image above provided within the white squares with values ranging from 70 - 120 knots (kts).

SATURDAY/SUNDAY: Coldest overall day, colder than today all areas by generally 3-6 degrees during the day and much colder Saturday morning all areas, as well as Sunday morning.  The warmest overnight lows will likely be EAST of the both rivers in Brevard County and southward. Same reasoning will apply far west coast south of Tampa. Lows do not appear will get to freezing except toward far North Florida, but mid-upper 30Fs and lower 40Fs could be widespread these mornings. Those warmer areas will likely remain closer to the mid-upper 40Fs, and warmer Keys and coastal SE Florida.

MONDAY: Still no change in previous line of thinking. Warmer east coast as onshore winds develop over night Sunday night or late in the day, preventing temperatures from falling along the east coast. No truly Cold spell   for QUITE SOME TIME TO COME also remains at this point;  only perioeds  "on the cool side" from time to time (so far). Maybe some showers or at least a cloudy period toward Wednesday with the next front, but as stated, cold air with this next boundary has yet to materialize more than a few tics below normal  seasonable readings.

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Thursday, January 12, 2012

Three Cold Days Ahead to Commence Overnight- Tonight

Cold days EMERGENCY  beginning Friday morning, although not as cold as in this image. We might be lucky to see blue sky to much of a degree for Friday and Saturday, unlike this pristine image shows . More below.

FRIDAY/SATURDAY: Okay, not quite an emergency, but this post does have urgency. Late day post this Thursday evening. Post haste make not waste, so it will be made brief.  

A second cold front after yesterday's, can't even tell one went through given the warm air  today, is on the approach as noted in Wednesday's post. The front will be across Central Florida between 3AM -7AM Friday morning  and   approaching the north shore of Lake Okeechobee during sunrise. Wind behind the front becomes northwest. Skies should remain partly cloudy at times over night..with mildly cooling temperatures as would be expected after sunset. 

The bigger change will be post-cold front early Friday as full cold air advection occurs during peak heating on Friday. This will offset the normal diurnal heating cycle, and in fact, temperatures will likely FALL all morning after sunrise toward noon or early afternoon. Highs Central remaining in the mid-50s and lower 50Fs far north central to upper 40Fs further yet north. South Central and South to be in the low-mid 60Fs, and maybe some upper 60Fs far south.  

Good chance it will become at least mostly cloudy mid afternoon as dense jet stream cirrus clouds and 500mb cirrostratus clouds are swept well overhead, blocking the sun's rays .

Despite the cloud cover blanket potential, lows by Saturday morning might still fall to the mid-upper 30F north half toward the lower-mid 40Fs extreme East coast (east of US1 toward Canaveral and South) and south Florida. Saturday appears will be the coldest day of this set up from sunrise to set, cooler than Friday by several degrees round the clock with continued cloudiness seeming to be a good bet. If the sun can be shining more than my line of thinking is this evening, temperatures will be easily 5 degrees warmer than noted in this post if not more. That does not appear to be likely though, even if the clouds are not as prevalent. Point is, back to the jackets and wind chills for a time.

SUNDAY: Frost possible Central and Northern Interiors, and warmer all areas by noon time or so, with highs into the lower-mid 60Fs Central, warmer south. East coast overnight lows Sunday night (east of US1 from Port Canaveral and South) might fall only very little after dark Sunday night.

MONDAY: Warming trend all parts of the state with a quick rebound. Onshore easterly winds   becoming more SSE toward Wednesday will prevent overnight coastal lows from falling below the low 60Fs. That is a big turn around to have overnight lows possibly warmer than the day time highs of Saturday and Sunday . 

BEYOND: The last Long Range model indicates a trend toward a chance of rain on Wednesday with another front in the area; however, temperatures are not expected at this point to fall to the low degrees of this front tonight or that previous one last week. If this year is like that of last year, this next cold snap might be the 'end all of end alls' for this season other than " onesies or twosies cold duration 'snaps' " 

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Wednesday, January 11, 2012

Gusty Winds Today, Rain Good Bet, A Strong Storm Possible

Mean Sea Level Pressure (MSLP) Lines and 10 Meter Winds AGL in Knots (Above Ground Level) per the Melbourne, FL National Weather Service (NWS) Website (see link in graphic). Front is shown in Gulf of Mexico. Expecting stronger activity today , if any, to be south of the red line. Prefrontal trough to be enhanced by late morning toward noon time with higher sun angle, although cloudy skies will prevail throughout the day offsetting  heating.

The above image shows where some boundaries at the surface exist. The satellite image shows what the sky looks like from above the clouds we see looking down toward earth.

CLOUDY skies can be see from space over Florida. Storms
are embedded within these clouds, mainly off Southwest Florida, with another small line becoming organized  about 60 miles west of Cedar Key near the lower Big Bend. The 'cold front' really is not much of a cold front seeing how it originated over the SW United States. The colder air is behind another front to come early Friday.

TODAY: Rain chance increases across the state today, although anticipate that not many areas will see the heavier rains. In fact, most areas will only experience light rainfall. A trace of rain fell in Canaveral near daybreak along with a "Red Sky at Sunrise". There is an old adage, "Red Sky in Morning, Sailor Take Warning".  Rain chances are shown by most of the model guidance to pick up late morning from west to east as daytime heating (albeit weak due to cloud cover) increases mid-level lapses rates (change in temperatures with height) to only a small degree. Otherwise, wind energy associated with the mid-upper level troughs which are propagating the surface front eastward will increase across Central and South Florida after Twelve Noon. At that time is when rainfall coverage could increase. Any storms will be embedded within the cloud cover, and will not be easily discernible upon their approach until very close to any one (your) location. Temperatures to remain in the low-mid 70Fs, possibly toward upper 70Fs far East Coast south of Brevard.

STORM CHANCES: As of this writing, a small cluster of storms with some lightning has taken shape well west of Cedar Key, FL which is located generally WSW of Gainesville, FL along the west coast. The biggest cluster of storms is well west of SW Florida in the Gulf. This cluster is closely linked to the warm Gulf waters of the Loop Current. It is thought by all guidance they will never make it to shore once they begin to depart those warm waters. So far, loops of radar and lightning animation seem to be verifying this line of thinking, but can never say never toward South Florida. For now though, the trend of several days has shown little activity over South Florida with this system, and early morning model runs have not changed along those lines.

Better chance appears now to be South of I-4 and north of a line running from near Sarasota to Vero Beach as was surmised yesterday. A few graphics are included below with descriptors.

Helicity is a measure of corkscrewing winds in the horizontal. The red shows higher helicity. The higher this value, the greater potential for lifting mechanisms in the atmosphere to act upon any shower or storm that can manifest in the generally unfavorable environment today. But one can never be sure in cases similar to those of today. In the past, a strong toward severe storm or two has managed to manifest regardless of preconceived notions. Believe the best chance of any such activity today over land will occur between the lavender lines, especially Brevard County. 

This above plot is as close to 'actual' as one can get. NOW, we can look at the Rapid Updated Cycle (RUC) model forecast plot for this afternoon around 3pm. This is  showing the Energy Helicity Index at the lowest atmospheric levels. The Green Shows at least 'something worth noting'. This value combines both helicity and Convective Available Potential Energy (CAPE) in the atmosphere...(long story).
01KM EHI  (Energy Helicity Index) per RUC. Note where the green is located. By the next hour in this run of the model, these values are even higher but have moved offshore Brevard, Southern Volusia, and Indian River County. Prior hours to this time frame show little. These are coincident with during and just after peak heating, no coincidence. Note another peak in green toward SW Florida. 

 ...For today, cloudy and breezy. Guidance shows winds of 40 knots just above the surface, so it is possible Small Craft Advisories and Lake wind advisories could be needed after 11AM toward late afternoon as the prefrontal trough and front cross the state. Guidance also shows winds could remain elevated to breezy well after dark. Winds from the South to SSW becoming SW-WSW at 14-22mph with gusts toward 32mph near any showers or possible thunder storms. The strongest wind gusts in storms should they be able to manifest COULD top 55mph, but coverage of such activity will be very isolated and therefore the Storm Prediction Center is no longer outlooking Florida for severe weather. The more favorable location is the Carolinas closer to the parent surface low pressure center.

Better chances for strong activity almost anywhere along the west coast toward West Central and SW Coast, as well east East Central. Brevard/Osceola, Eastern Orange, and Indian River Counties seem to have a better chance of stronger winds and a brief but heavy down pour, not to discount Northern Palm Beach and Martin Counties as well. Cloud to ground lightning is possible as well, but very isolated. Expect most lightning to be  in-cloud or cloud to cloud. 

It has not rained heavily in quite some time for most areas, so it is a good point to be made that roads could become slick easily today, and will be traversed during rush hour while still wet. The biggest threat today will be the roads, although some gusty winds and who knows, maybe a brief 'spin-up' like tornado toward East Central, but definitely not hanging any hats on that hook.

BEYOND: Front to clear the state after dark, and become draped out across the Florida Straits close to or just south of the Keys until the true COLD FRONT crosses the state overnight Thursday night and very early Friday. 

COLD AIR ADVECTION ALL DAY FRIDAY..meaning, cold air filtering in on NW winds even during peak heating. Breezy on Friday and cold, becoming cloudy as well due to the potential of fairly thick altostratus and cirrostratus sun. Hopefully, this will not be the case, but if so, could be highs Central and North will never breach the lower 50Fs, warming into the lower to mid 60Fs South Florida.

will be the potential real weather maker for rain related activity, although showers can accompany the actual front in blue as well. Partly cloudy on Thursday with increasing clouds late as the next front approaches

 THURSDAY OVERNIGHT: Jet  streak of 140 kts winds aloft will be departing the SE States placing Florida in the left  exit region (right rear quadrant)..this generates lifting in the upper levels and could induce cloud coverage during the time of cold air advection.
A lethal combination!! for those not favoring cold weather.

FRIDAY - SUNDAY: Much like those last days that were cold. Winds become light with some sunnier skies but remaining very cool during daylight hours through Saturday and even Sunday to of less a degree. ..but morning lows to not appear will reach freezing, and even frost might be hard to come by due to light winds.

MONDAY: Cool start and then rebound. It still appears another stormy system will be on the horizon around week three of January, but this system now on our door step and the cold air to follow over the weekend and Friday might just be the end of the worst in the temperature department. Just Maybe.

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Tuesday, January 10, 2012

Strong To Severe Weather Possible on Wednesday

Latest visible satellite image from this Tuesday morning. A cold frontal trough is taking shape into the GOM (Gulf of Mexico)..shown. The Low over Texas is in the upper levels with a surface low further to the east in developmental stages. High pressure is gradually easing off the east coast of Florida with very light winds over much of the state gradually becoming SE-SSE today and S to SSW-SW on Wednesday as the high pressure moves further away and the front approaches.

TODAY: Peninsular Florida in the prime time of niceties today. Highs in the mid-upper 70Fs (do I hear a low 80F somewhere?)  except near the beaches and their cooler sea surface temperatures. Light winds and only a few clouds except toward the Panhandle and North Florida where denser clouds are producing potentially light rainfall over the Panhandle or at least dense cloud cover.  The image above is annotating areas of potential weather wary concerns for Wednesday. More on this in the next image.

Overnight lows tonight in the 60Fs state wide as clouds and moisture increases and winds become due south and pick up toward the 10mph range and stronger toward daybreak.

WEDNESDAY: Front crossing through. Winds becoming S-SSW at 12-20mph, possibly gusty. Increasing clouds Central and South right after day break with rains and possible storms already in progress NW Florida approaching the West coast from near Sarasota and north then across toward JAX early through mid-morning.  Winds at various levels of the atmosphere per the morning GFS Model Forecast Run show  sufficient speed shear / bulk shear  and even a little directional shear toward NE Florida Southward toward Ocala/Daytona/Sanford/North Titusville working into early afternoon, through various levels of the atmosphere to support winds gusts in the 40-55mph range in any heavy rain storm or thunderstorm. Thus, believe there COULD be a severe thunderstorm watch in affect at various times for different areas beginning early day through early evening (South Florida). Image for 10AM tomorrow morning per the GFS run with personal annotations...below:

In red is where I'm thinking lies a potential for severe winds at or above 58mph in gusts or even brief straight-line in any thunderstorm that can organize. Could be a brief tornado 'spin-off', but organized Deep Layer directional wind sheer is not really appearing to be sufficient for a flat out call on such formations as of this morning. South of the most southern red line, potential strong winds below severe category. Note that there is a second front to come some time toward overnight Friday night/early Saturday.
WEDNESDAY (CONT'D:) Rainfall to progress from west to east (and southward) during early to mid morning, first impacting the west side of Florida as far South as Sarasota well before reaching far East Central. Could be hearing strong to severe storm reports filtering in by mid-morning well before rainfall reaches the east coast. The Storm Prediction Center early today has ALL of Florida under a "See Text", meaning they are watching the situation, but not ready to hoist any 'for certainties' for a severe potential. If that were the case, Florida would be in what is referred to by their stringent guidelines as at least a "Slight Risk" (for severe weather). "See Text" in this case could mean that wide-spread severe weather is not expected, in which case any alerts or warnings to be issued will be on a case by case basis, and are not of a high enough threat at this point for the state to be under closer scrutiny for a full blow 'threat' .  Rainfall should be reaching south of I-4 after 12-1pm and progress Southeast ward through the remainder of the state mid afternoon through mid-evening before ending all areas well before midnight Wednesday evening.

THURSDAY/FRIDAY: Westerly winds and partly cloudy skies with highs in the lower-mid 70Fs and lows in the 50Fs..partly cloudy. The second front is forecast so far to be crossing through overnight Friday night toward Saturday morning. The details on this boundary's passage will need to be refined as the time draws closer.

WEEKEND: Drier and much cooler to cold in the mornings. It is possible highs will never crack 60F Central and North on Saturday, with a slow warming trend albeit remaining below normal on Sunday. Cool start Monday morning with what might be a big recovery into mid-week next week as temperature recover to seasonal norms, if not a notch above those.
"Cloudy With A Chance of Meatballs"

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Monday, January 9, 2012

Tale of Two Fronts On The Way Mid-Week

Sunrise This January Morning. Image is a video clip take from the actual video now on YouTube

TODAY: Nice Sunrise This Morning. Video can be viewed at

Otherwise, High Pressure is centered very close to if not over the Florida peninsula today as a complex frontal boundary gathers its wits across the Deep South with low pressure centered over North Central Texas. This system will progress eastward through tomorrow with snow as far south as San Angelo and Midland/Odessa area toward the lower panhandle region.  Meanwhile, the high pressure over Florida will be slowly progressing east and off the Peninsula during the day on Tuesday with southerly winds slowly ensuing. Temperatures to remain quite pleasant at to just above what would be considered seasonally 'normal'.

TUESDAY: Light winds again, with increasing cloudiness ahead of the approaching front, especially over portions of North Central Florida and all of North Florida. Some strong storms are possible over the Panhandle beginning late day Tuesday into Tuesday evening.

WEDNESDAY: Cold front will be approaching. South winds becoming SSW during late morning toward noon time. Becoming mostly cloudy with increasing rain chances from NW to Southeast from sunrise to sunset. At this time, would not expect any or very little rain to fall south of I-4 until after 1-2pm. Strong toward severe category storms due to strong winds are possible, mainly north of I-4. Even if no thunder is heard as far south as a line from near Vero Beach to Sarasota and north, stronger wind gusts are 'possible' due to the strong nature of the winds aloft being dragged to the surface (ground level), especially in heavier rainfall areas.  The front will continue through the remainder of the state, impact Central and South from early-mid afternoon through sunset, clearing the state by mid-late evening.

THURSDAY: Not much all that cool really, another front is on the way toward the weekend. More details concerning that boundary in a later post. So far, the guidance has been holding back on the second boundary being a rain maker; however, the trend is toward the temperatures again becoming very cool toward cold 24 hours a day, not unlike our last event...most notably this go around toward the South 1/2 of the state.

HERE IS AN IMAGE FROM THE GFS with a hand plot of fronts and pressure systems for WEDNESDAY MORNING. This image is derived from the 7AM run of the Global Forecast System (GFS) computer model forecast for only the surface parameters. This model shows wind fields, temperatures, and atmospheric moisture content all the way up toward 35,000 feet above ground at what is considered in the field of meteorology "standard constant pressure heights " in increments of millibars. Again, this is only for the surface, or in other words, what it would look like in the morning newspaper.

GFS Surface depiction for Wednesday morning. The fronts and text have been drawn in for explanatory purposes. 

BEYOND: Note there is the second front to come. It is behind that front the cold air will arrive, which could be a good 36-48 hours after the first front on Wednesday. There has been a fairly strong signal that we will again be fairly cold once again in Florida, and perhaps another good chance we will encounter and even greater severe weather threat heading out of week two of January toward week three. Realize, the last week of January can often be one of the coldest of the winter season, being as it is one full month after the lowest sun angle (December 22nd). There is a time lag as the earth's surface is still cooling. But, one can never know for certain. Last year, our coldest days were over during the beginning part of January.

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Saturday, January 7, 2012

Winds of Change Beginning - Up to 3 Rain Chances Possible Toward Mid-Month

If only the weather was a simple as a posted sign. The sky does have it's signs when one learns how to read between the transparent lines. 

Infrared Satellite Image and Animation Prior to Daybreak indicates that  mid-upper level clouds shown by the gray to white color scheme are moving from the west toward the east. Model guidance clearly shows this influx of moisture aloft as dictated by its depiction of moisture aloft. This moisture will be in place in varying degrees, mainly across the north half of the state and a portion southward toward North Lake Okeechobee all day, thinning out a bit toward mid-late afternoon.
This image shows the moisture aloft from a different perspective. Data acquisition interpolation plotted out in color codes, with blue being the most moisture. The wind barbs point from west toward east. Animation of the satellite image shows this is in fact the direction of cloud motion  

Winds of change, meaning, model consistency in a broad sense indicates the days of cold are coming to an end, and chances of rain are entering the mid-long range time frame in the second and third weeks of January. It has, afterall, been quite a while since any rain has truly been in the forecast. There is a chance that not only rain chances, but strong to winter time severe storms will be possible heading toward mid-January into Week 3. Long range temperatures are not expected, so far (fingers crossed) plummet to those experienced recently. This was the prognosis in recollection of an earlier post for the future, and so far  this is holding true to form. Can't even really be sure but the signs are consistent. Cannot  hurt to gaze forward in possibility. Meanwhile...

TODAY: It is Saturday, January 7th. As can be seen in the images above, a mid-level ripple in the atmosphere (short wave trough) is passing over head accompanied by moisture. This can be seen on the satellite image and in looking outside, I see an orange/pink sunrise beginning to aspire. Winds are dead calm and temperatures statewide are running in the mid 40s toward lower 50Fs. Warmest temperatures are under the thickest impinging cloud cover toward the Tampa area where the clouds act as a blanket aloft, not allow warmer air from the previous day to escape into the atmosphere. Like yesterday, there is wide spread fog , some very dense, in many areas. Areas outside of the fogged in locations remain unaware that neighboring areas are experiencing this fog. The fog will lift out by mid-morning at the very latest with highs in the upper 60Fs, although some mid 60Fs where clouds are most prevalent are possible. Actual high readings could be in the lower 70Fs, but I would not expect that to be the prevalent modus other words, only relatively briefly. Most  likely toward Lake Okechobee and South where clouds will not be as prevalent is where consistent 70Fs will occur, unless clouds are not as prevalent as current line of thinking is depicted.

TONIGHT Thru TUESDAY: Gradually warmer overnights by a few degrees as well as days. A few clouds, light wind, and some near to right on "True, Blue, and 72F" fact, possibly even warmer, especially on Tuesday with highs in the mid-upper 70Fs (south).  A cold front will be on the approach; the jury is out concerning its impacts as far as how much, where, when, and how strong rain will fall including a strong storm potential. It is my inclination this go around to preclude a severe threat, although it is tempting to consider it given the forecast wind fields on the GFS model. Thus, watching the Wednesday time frame for at least rain and maybe more than simply that. If conditions warrant a more in-depth detailed low down,  we will delve into this day with more in-depth analysis and description in a future post or posts. 

WEDNESDAY:  As noted above, a possible pre-frontal trough and associated cold front will bring in the biggest chance of rain we have had for quite some time. Not necessarily at this conjuncture that it is 100 percent certain...but we are leaning that way. The good news though, is that it does not look to get much colder after the boundary passage than it is this morning.

BEYOND: Though it will not be getting much colder, there is a reason. This could very well be only the first of up to 2 more fronts within a one week to 10 day time frame, each carrying a rain potential..and each with a chance of greater impact and accompanying strong to sever storm investigation as an over all pattern in the wind fields at all atmospheric levels takes place. 

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Tuesday, January 3, 2012

Wear Layers Through Wednesday

Layers of the Skin. Layers of Clothes Add Protection to our nerves and warmth  from Wind Driven Cold Air That Penetrates the Top Layers of Our Skin. This added layer (s) will be necessary in varying 'degrees' through Wednesday. By Thursday late morning, we can start shedding.

TODAY: Not doubt it is cold outside today, even in the sun. In the sun protected, but wind driven shade it's a different story, downright nippy. As of 1:15pm it is 43F degrees at this location from home, colder still to the North and North West. Far cry from summer's 93F at this time. No need really to go into any fine details, since this is the story, with none other to discuss. The high pressure circulation drawing south the cold air will rotate more toward the state than retreat back to the west a bit tomorrow as another 'short wave' ripple in the atmosphere passes by. This will only change the wind direction back toward the WNW as it begins to retard in strength in the next 48 hours. Nonetheless, the cold air will continue tomorrow, albeit a bit warmer tomorrow by several degrees after noon time. What is very interesting is that dew points are running in the single digits in some locations around the Central and Northern Portions of the state..with lighter winds tonight..this will allow the ambient outside air temperature to fall all the more. Thus, there is FREEZE WARNINGS in affect for basically everyone who reads this post, except far toward South Florida and east side very close to the beaches from Brevard and south.

WEDNESDAY: Cold morning everywhere except as shown in the image below...that is to say, it's all relative. The east coast from near Canaveral and South will likely be spared the worst with a low in the 33F- 38F range, but elsewhere lows will range from the teens to low 20Fs near and north of I-10, warming toward the mid-20Fs to low 30Fs range most other areas statewide except as shown in the image. Blue indicates 30Fs and 20Fs...the narrow green along the east coast is closer to 40F, but this might be just a tad too warm as indicated by the latest GFS surface temperature depicted.

Note the 'green' along the coasts. Yet, blue extends well into the interior southern portions of the state. Light winds over  the Panhandle could drop the temperature shown here significantly lower than shown here, especially with the very low dewpoint temperatures into the teens and single digits.
BEYOND: The biggest jump upward in temperature first appears will occur on Friday afternoon, and from there on out through the weekend we will be returning to climactic norms, with lows in the 40Fs to lower 50Fs, and highs in the 70Fs. No rain on the horizon yet.

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Monday, January 2, 2012

Winter - For Real - Arriving As I Write This Post

Microscopic View of Frost. Note the amazing order in this realm of frozen moisture madness

TODAY: No need for a weather map today. Fact is, a cold front is passing down the peninsula this morning as the sun rises, and will continue onward to the South beyond the southern tip. What's there to see? Wind behind the front will come from the NW around 12-18mph, possibly breezier toward the Barrier Islands as cold air intrusion collides with warmer air  wafting just above the waters of the rivers...although strong winds are not really anticipated , the wind chill will become notable by late in the day as the sun starts to set and we lose solar heating within its capacity. Highs not likely to get out of the 60Fs today except toward South Central and South Florida.

TONIGHT/TUESDAY : Another influx of cold air tonight on continued NW winds. Coldest overnight to early morning since last winter earlier in that season. Lows in the low-mid 40Fs coasts, mid 30Fs through low 40Fs interiors. The National Weather Service is already sending out the alert of a wind chill advisory for all of Tuesday through at least late morning, apparent temperatures in the 20Fs. Some areas toward the North could see some upper 30Fs, with highs possibly not making it out of the 40Fs on Tuesday after the second surge. Time to pay the winter piper's dues at long last. The inevitable arrived.

WEDNESDAY: Possible frost away from the immediate coast, as well as some freezing temperatures toward Northern interior of North Central, but 30Fs are possible as far south as NW Dade County in rural Miami area and elsewhere, everywhere statewide (other than the Keys). Closer to 40F from the Barriers of Southern Volusia and South along the east coast within a mile or so of any coastline, except the Panhandle and all of Northern Florida where it will be colder. Lighter winds just might allow for frost formation, impacting agricultural interests of any kind, including home plants that are outside. 

Thankfully, the lower wind speed will reduce the wind chill factor, with the chill factor being the resident occupant. In other words, cold by our standards and what we have been acclimatized  toward. Point blank, we're not used to this. Thermostats might have to come on to heat mode. I have yet to turn mine on since that last time it was turned off a long time ago last year. A little warmer by afternoon though than on Tuesday with highs in the 50Fs to lower -mid 60Fs (South Florida).

THURSDAY/FRIDAY: Very cool/cold starts, but it does not look like it will not be as cold as Wednesday morning. Warmer in the afternoons as well, and from the afternoon onward subsequent days should be progressively warmer , approaching near normal for the weekend.

WEEKEND: Back to where we started, like yesterday's weather. Another front or two is forecast to press through heading into week two of January, but not with the impact of these two that are front and center. Will this be the worst that winter has to offer this year? I have doubts, but so far, that is what is being depicted by the overnight run of the Global Forecast System into mid-month.

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