Worst Drought Area Might See Some Big Rains Today

Chance the Some Storm Activity Could Propagate Off the East Coast as Light Rain
but more likely that Some Large Totals 'Might" Amass "Somewhere" over Interior Counties.
Watching Osceola and/or Eastern Polk County for now

TODAY: A bit different today than yesterday. KSC sounding expectantly came in colder aloft than yesterday and more moist. If it be correct and representative across a large enough area, steering from the WSW is a bit stronger today as well, at least north of Melbourne. 

Looking outside at the lower cloud motions, it does appear to be the case. The convective temperature was set at 89F as of sounding time which spells out at least 2PM for 'beginnings' but true going showers into storms is not expected to commence until around the 4pm time frame and to quicken on up from there on out.

Initially we could see showers form along the West coast sea breeze from the Big Bend area and south as well as along the east coast sea breeze near the St John's River Valley Basin (Northeast Florida), in tangent with activity in from the coast down to Brevard. Some of this could be quite close to the coast (to at least hear 'Thunder on the Beach' from Canaveral northward, to possibly moving off shore north of the Cape). Otherwise, strongest activity will have to with until sea breezes meet accompanied by early activity outflow mergers.

Chance that activity will propagate then south and west toward SW Florida very late in the day into th early evening. That area this morning is atmospherically more dry than Central Florida and by in large far South Florida will have to wait for activity to move into that area from the north as it looks now. 

It also appears there might be a remnant boundary across Central from just north of Sarasota toward the Mims area which might act as a triggering mechanism in that area early on toward the 3:30-4:30 time frame. 

Overall, the 'red areas' in the image above are to depict where there might be a strong storm worth making a Special Weather Statement or even a warning over...or even in East Central the chance of larger rainfall totals. The latest NAM model is hitting hard on the east half of Osceola County for totals of up to or over 3" by the time all is said and done today. So if for nothing else, will be interesting to see what comes out of that if anything, and would be helpful for drought relief purposes.

THURSDAY: Latest guidance indicates a variation of today with perhaps a late start and activities further from either coast. Again, and as can be typical of the wet-season type rains apart from any synoptic (larger) scale influence, whatever occurs the day before can have some influence on what will occur where at the beginning of the following day (though not always). There are some interests tomorrow in regard to a Launch at the Space Center set for late afternoon, which 'might' be threatened if nothing more than by extensive cloud cover for viewing purposes.

FRIDAY INTO THE WEEKEND; Again, guidance does really increase overall atmospheric moisture content in excess of 2.00" (today the Cape was showing about 1.74")  and thus spits out numerically bigger rain chances by percentages. 

I am still skeptical however that higher PWAT (precipitable water values) will equate to higher rain chances.

 It might mean but more cloud cover instead. For example, the last several runs of the GFS have shown very little instability at all in the low levels of the atmosphere and lower afternoon high temperatures during the same time frame implying cloudier conditions and more stable over all, even though very humid.

 GFS rainfall depictions do show showers/storms...mainly nearer the coast which is always possible.  Latest GFS run shows CAPE (convective instability) at only around 500 j2/kg2s both days this weekend which is very low (stable) as far as summer goes. By comparison today the CAPE is forecast to run around 2000 j2/kgs near the immediate east coast and 1000 -1500 inland.

In other words, not so sure it will be all big rain chances this coming weekend as opposed to cloudier. Time will tell.

Chance of Showers/Thunder (Isolated Strong) Today

Sunrise Monday Morning

TODAY: Changes to the overall 'scheme of things' at hand to commence during the mid-late morning hours. Temperatures aloft will decrease (become much cooler) as the influence of an upper level trough down the east side of the country becomes the ruling influence as opposed to warm temperatures aloft that were present under the reign of a high pressure ridge. As a result, the capping aloft which prevents rising motion will no longer be an issue that prevents showers from forming.

With cooling aloft, ample low to mid level moisture, and convergence along sea breeze / lake breeze boundaries we should be able to get showers and storms to manifest today. Much rain is needed to alleviate the now 'severe to extreme drought' conditions across a large portion of Central Florida.

Recent short term guidance implies even a rather 'early onset' as meaning beginning around 2pm near Eastern Osceola or Western Brevard County as well as up by NE Florida and far SW Florida as well. Exactly when activity generates and where might determine where any stronger storms will end up being later. 

If any area has a storm 'earlier on'..it is unlikely that same area would see the chance of a 'stronger storm' later as the area will have already been worked over (stabilized by rain cooled air).

Steering today will be slowly toward the east coast, with the best chances of rain being experienced at the beaches proper from Indian River County and North (though only in spotty fashion).  Many areas will not see rain today as well, especially near and west of Route 27. The stronger storms would like be a bit in from the coast nearer to the I95 region or even further into the interior.

The only fly in the ointment is a thin layer of cirrus clouds evident on infrared satellite imagery as of 545AM (see below). These aren't going away any time soon, but would watch to see if those wouldn't point toward a later storm / shower onset that guidance implies.

WEDNESDAY: So far, guidance points to a near carbon copy of today, but with perhaps a slightly higher coverage of activity.

BEYOND: Things begin to change mainly in regard to 'where' rain will fall, with a shift more toward the interior alone, and eventually (perhaps more toward the west side of the state. The models have been deviating a bit though in many regards in terms of exactly how much high cloud coverage there will be going into the weekend.

 Numerical output reads 50/60% chance of rain..but are they seeing moisture related to high clouds? Too soon to say. As noted yesterday, the rain chances even get a boost heading into the first week of June around the 3rd or 4th but am skeptical at this point.

It's Beginning to Look a Lot like Summer

Sunday Morning Paddle Out 

TODAY: Increasing dew points (running in the lower to mid 70Fs early this morning) means increased humidity.  Compared to 20-30F dewpoints (and lower most of the time in the winter).

The increased humidity with dry air aloft and a mid-level capping means nearly hot AND humid as well, over the interior during early to mid afternoon. The high down by Miami proper yesterday was 98F if that was harbinger. 

Today very warm with wide spread mid-90Fs inland and some isolated upper 90Fs down along the St John's River Valley Basin west of JAX into Central and parts of South Western Central Florida as well; warmest locations appears will be near and north of the Orlando area.

Otherwise, though moisture is lacking at time it is increasing hence higher dew points and a more humid feel to the day will be at hand as opposed to what it was like on Friday and Saturday.  Temperatures aloft are a bit warm so hard to see how deep convection (thunderstorms) could get really going today, even rain showers. On the other hand, with sea/lake breeze convergence at play with the moisture  to continue increasing...there could be some 'accidents' today resulting in showers across South West Florida and up along or near Rte 27 to west side of Orlando and/or even as far north/east as Western Volusia county after dark. That would be on the high end of the rain-chance potential spectrum, to maybe even have some lightning "Central very late". On the lower end of the spectrum potential is very little rain chance much of anywhere.

TUESDAY: Again, warm with a better chance of shower/storms as noted in previous blog post several days ago.  Guidance is still  rather bullish on overall coverage and is shifting around on where rain will fall. Will side with the more consistent GFS and place the better rain chances near to west of I-95 from Indian River County and north toward St Augustine late in the day with isolated potential any other interior location. Temperatures aloft are expected to be much cooler tomorrow , instability sufficient, and moisture still in place.
There is a bit of an easterly push aloft in place which might put the east coast beaches into the 'rain chance' realm after dark (though it would be light, unless things change between today and tomorrow which is always possible).

WEDNESDAY: Again, like Tuesday with seemingly an even better rain chance of sea breeze convergence activities up and down more of the peninsula but again favoring the more northern 1/2 to 2/3 of the state over  Interior regions. Again, chance of a push back toward the east coast or at least anvil/debris blow off making for cloudier conditions toward or after dark on the east coast north of Lake Okeechobee.

THURSDAY: Perhaps again a chance of thunder/rain however upper level cloud cover from cirro-stratus or alto-cumulus cloud decks might actually put a big strain of whether storms can even form, especially going into Friday-Sunday. ON the other hand, increased cloud cover means not nearly as hot for afternoon high temperatures. Will hold off on specifics for this time frame in regard to rain/storm locations or their favor-ability due to the potential of the aforementioned cloud cover coming into play make rain chances nearly nil except in some locations. Even without cloud cover this day, the more western side of the state is favored.

Heading into the weekend might not hurt to be watching for showers closer to the coast in the early morning hours toward late morning though afternoon rain chances might be on the decrease due to hints of increasing upper level cloud cover possibly all weekend. That would mean, 'so much for a completely sunny weekend' -- unlike our previous one.  

Does all of the above said spell "Wet Season!"?  Not necessarily just yet though 'climatologically' it can and has begun this soon, but also much later into the second week of June. The GFS implies what looks like  the more 'assured' reality of the Wet Season and hence drought relief to be more likely heading toward the June 3-5 time frame and beyond so either way it won't be long now.

"Risk' For Severe Weather Through Early Thursday - Could Wet Season Begin Next Week?

Current Storm Prediction Center Forecast (SPC) Valid through 8AM Thursday Morning.  Area  in-between the 'orange arrows' for blog purposes only
 (and at time of 'certain' interest only to the blogger for future reference)

TODAY: As of 8AM EDT the Storm Prediction Center (SPC) based in Norman, Oklahoma has 'upped the ante' on the 'Potential' for severe weather today in parts of Florida which could occur at various times (even into early Thursday at this point)  All modes of 'severe' are possible which would include wind gusts of 58 mph or great, hail of 1" or great, and a few tornadoes.

As of earlier today the greatest risk is across North Florida where at 10% tornado risk area has been sketched out. Their forecast will be updated again by 2pm this afternoon   A Tornado Watch is also  in affect as shown below.

The greatest risks are for 'severe category' winds and 'weak tornadoes'. See graphic and color coded key to the graphic below.

Though there is only a small amount of activity currently at time across North Florida (including a tornado warning at time of typing) it is expected that radar will look significantly different (much greater coverage of storms) by all model  in the next few hours toward noon and early afternoon and work south and east with time.  

In fact, in just the hours between 7AM and 10AM it has increased GREATLY. Earlier there was but one or two storms across North Florida. However, as of 10!5AM...the radar now looks like as shown below with the tornado warning shown along the NE Coast.  

Compare as seen below the difference of over only the course of three hours.

Radar at 7AM

Radar at 10:15AM

EARLY-MID AFTERNOON: By this time a new SPC outlook will have been released. Latest HRRR (high resolution rapid refresh) model runs have continued to imply areas over almost all of Central Florida, especially east central, could begin to see showers or even some thunder to develop rapidly and move offshore as winds aloft will increased along with the wind shear aloft and increasing helicity values as well. Some could start to form prior to noon time in isolated fashion and are not at first expected to be a 'threat'.  

Strongly suspect another Tornado Watch will be issued to cover the regions south of the current watch to as far south as a line toward Martin or St. Lucie County if not the rest of the state.

In summary, best option for the reader is to 'tune in' to local television broadcasts or whatever resources have proven to be most effective and efficient, such as your NOAA Weather Radio. Seeing the TV radar and hearing the analysis of what is being shown is worth the while, and would be advised (if possible) beginning early afternoon. Channel 7 usually does a good job but any channel will do.

Early Morning Depiction of the 'Sig Tor' parameter on the HRRR model.
Since that run these values (see color coded index) have decreased a bit but the general location remains the same .  Areas all the way down to South Florida are also at 'threat' going into the over night hours.
This could all change , however and as such
is not in the forecast from the SPC, at least not as of 8AM

OTHERWISE: Going into tonight, especially after 500PM things could really begin to 'ramp up' for all of Central South of I-4 and north of a Vero Beach to Punta Gorda line. 

The 'window of opportunity' appears to be rather long (up to 6 hours) for more than one event in any given area. 

Some areas will have a decent shot of rain more than once, as a result, going into Thursday morning when all is said and done right over the worst drought stricken areas even. A plus there.

AFTER THURSDAY AND INTO THE WEEKEND: Dry and pleasant with warming temperatures into the weekend. That is to say Friday - Monday. By Late Monday a new song might need to be sung for the beginnings of a more wet period per the last few runs of the GFS model.

TUESDAY- SATURDAY NEXT WEEK: Though this is too far out for accuracy's sake, it is being implied that another upper level trough will attempt to dig down the east half of the United State though not nearly to the degree as it will be doing so in the next 24 hours including today (and will be the cause of the Potential Severe weather being forecast).  

Regardless, with warming temperatures, ample moisture, sea breezes in effect and the climatologically favored time of year for the wet season onset, all parameters so far are shown to be in place for the chances of showers and storms in the afternoons mainly over the interior but even close to either coast (at first the east coast, then later the west coast) as time wears on. This will need to be revisited however for consistency during the next couple of days, but if so it looks like the beginnings of a slow but sure wet season pattern, which might come and go for several days at a stretch. Not unusual.

Chances of Eastern (Interior) Thunder - Even Rain at Coast (Late) Some Areas - Severe Possible Wednesday

TODAY: Upper level trough from the west is slowly approaching Florida (for some possible 'eventful weather Wednesday and/or Thursday' as surface ridge axis  which had been north of Central Florida begins to drop to Central and even South Central (weakly) late in the day.  Best overall atmospheric moisture is so far shown (and forecast) to be north of Lake Okeechobee today. Strongest 'west to east steering will be from near Melbourne and north though quite weak and not strong enough to overcome the east coast sea breeze from Brevard and South. 

The west coast sea breeze appears will be the dominate feature today and to press eastward the most and first across the northern third of the state. First activity overall for mid afternoon could initiate across NE Florida sending outflow southward and regenerating / propagating more activity southward with time..as more activity along the east coast sea breeze presses down  I95 across Flagler / Volusia Counties and then back to the east more into Seminole/Osceola Counties late day along the east/west coast sea breeze collision. Some of this activity might be able to press off shore with thunder mainly north of the Cape but some shower activity with 'rumbles aloft' might make it to the beaches from MLB and north.

Further south and much later toward the 6-8PM time frame activity will be strongest west of I-95 (as it appears now) near Seminole/Osceola Counties and Central/Eastern Orange county as well (perhaps). Guidance differs on how far South true thunder along I95 will manage. The 4KM NAM shows storms as far south as St. Lucie County whereas the latest HRRR prefers Central into Osceola County as the southern most activity.  The HRRR was way off earlier today though and seems to be latching on to what the 4KM NAM is seeing (which on the other-hand might be over-done) which liked the idea of storms even further south.

Will compromise between the two as written / drawn (image) above. Elsewhere, sea breezes from both coasts accompanied by Lake Okeechobee Breeze convergence could manifest some thunder over the general Glades area as well.

TUESDAY: For now guidance implies even more favorable for thunderstorms up and down the east coast in regard to the wind parameters but lack of moisture might mean 'no dice' on storms Tuesday ;   might require revisiting this tomorrow to see if that is still the case.

WEDNESDAY: Highly unusual pattern aloft for Florida is in the making. Upper level trough in a position that looks more like winter (with a 100kt jet stream as well) with strong wind aloft over Florida and appears ample instability resulting in bulk shear sfc-500mb of about 40Kts with temps running around -8 to -10C could produce storms with strong wind / small hail. GFS implies it is possible the east coast sea breeze if it can form will remain pinned right at the coast and have little effect an adding an additional boost to the storms if they can manifest. 

Precedent cloud cover is going to be a problem for storms to form is the big fly in the ointment (suspect) especially south of I-4. The Storm Prediction Center has taken a broad brush on this day as a result of the synoptic scale situation placing  much of Florida in "Slight Risk" for severe category storms on Wednesday already.

THURSDAY: Timing big issue this day, but appears instability will be sufficient from Oak Hill (well south of I4) for a storm chance again from Brevard County and South as long as the surface trough axis associated with the upper level trough does not press too far south over night Wednesday and early Thursday. Wind aloft this day in the jet stream up to 100kts. Could be an 'early onset' day if storms get going this day..and will be interesting to see if it doesn't end up being 'the day after the day' that ends up being the 'most interesting' in regard to strong storms (particularly for parts of South Central/ South Florida). The Storm Prediction Center so far is not 'out-looking' this day.

BEYOND: Drying out a bit and so far the Memorial Day weekend looks warm and dry though Sunday especially from Central Brevard and South along the East Coast might begin to see shower activities. Too soon to say at this point and will work on that as later (and more accurate) model guesses come out during coming days ahead.

Dry with Near Record Highs Mid-Late Week

Arcus Shelf on the Leading Edge of a Thunderstorm Encroaches on Cape Canaveral

TODAY: Cool start to the day with near calm wind - pre-dawn temperatures running between lower 50Fs inland to 60F or just above closer to the ocean's edge in a few locations in the proximity of warmer ocean waters now running near 78F (at Port Canaveral for example). 

Otherwise, mainly clear today and warmer than yesterday (mainly inland). Coastal temperatures might run close to the same as yesterday once the sea breeze sets in , mainly lower 80Fs.

MONDAY-TUESDAY: Little change to the overall scheme of things. Again, cool morning Monday rapidly warming within the first 90 minutes of sunrise, even more so after the 10AM hour toward noon. Again perhaps a bit warmer than today inland though . By Tuesday morning morning lows will also be moderating. Wind  remains light.

WEDNESDAY-FRIDAY: Implications being impressed by the Global Forecast System (GFS) model are for highs in the lower-mid 90Fs, perhaps breaching the 95F mark in a few locations almost anywhere well inland. 

Whether these will be 'record breaking or near-so' cannot say, as do not have daily record data available. The record high for yesterday was 92F (set in 2006), and temperatures this mid-week appear will easily breach that mark. 

Coastal temperatures will   seasonably  be   mild in presence of the sea-breeze with highs more toward the mid-80Fs but perhaps upper 80Fs to near 90F if the sea breeze were for some reason have a late start. With sea-breezes both being active  and moisture gradually increasing we'll begin to see more cumuliform clouds as well.

Toss that Beat in the Garbage Can

NEXT WEEKEND: Next chance of rain or thunderstorms commences Saturday. The GFS is minimal on rainfall in association with the frontal boundary that would herald the rain chances , however, so bears watching. Suspect it will change in it's outlook once Tuesday or Wednesday rolls around. 

Otherwise, the rainy season usually enters into the picture anywhere from the last week of May to as late as the second week of June some time. Couldn't be soon enough, as parts of Central Florida interior are in a "Severe Drought".

Chance of Showers/Thunderstorms Late Today through Mid-Day Friday

Evening Storm Off Shore Cape Canaveral, Florida  - May 5, 2015

TODAY: Rather complex forecast in regard to timing of 'potential' rainfall periods and intensities thereof today from late afternoon toward early afternoon Friday. Will use this post to describe one of the possible  scenarios that at time is being implied will evolve across two particular models --the NAM (North American Mesoscale Model) and the HRRR (High Resolution Rapid Refresh)

Current initial boundary producing rains and some lightning across Western Panhandle (see below image)  is advancing east. This boundary itself is not expected to have a 'direct' impact on peninsular Florida. 

During the day increasing SW Flow just above the surface should abet in propagating the west coast sea breeze well beyond the spine of the state while the east coast sea breeze runs more parallel to the coast with a much slower inland progression. 

Sea breeze convergence coupled with sufficient instability and slowly  increasing winds aloft coupled with seasonably cooler air aloft could set off a broken line of heavy rainstorms and/or thunderstorms up and down the east coast from near Daytona Beach and southward sometime after 5PM toward 7PM. Further west expect mainly showers along the leading edge of the west coast sea breeze , mainly near Rte 27 and eastward.

Some storms (near or east of I-95) might end up being on the 'strong side'  , mainly from Central Volusia southward due to the better chance of low level convergence/forcing along the sea breeze and less late afternoon cloud cover in those areas.

TONIGHT: Meanwhile, a cold frontal boundary will still be on the approach toward Central Florida prior to sunrise Friday. Timing on the boundary is still a bit sketchy though it will clear all of Central before mid-late afternoon .

Latest NAM guidance has been consistent on potential rains and even thunder to enter into the region south of I-4 near sunrise but then again, could be delayed toward noon time or so. The areas most likely to be impacted by this secondary boundary appear will be north of the Ft Pierce area and south of line running from Jacksonville toward Cedar Key on the west coast (see below).

 Again, there is the remote chance of stronger storms especially along the more northern areas (e.g., near to just north of I-4), but then again possibly toward Central as well if the boundary is delayed until late morning. 

FRIDAY NIGHT: Either way, rain chances will end all areas from North to South - first by mid -morning , North..then late morning to early afternoon North Central..to Central to South Central heading toward mid-late afternoon. Clearing sky conditions systematically work in behind the end of the rainfall, but exactly when a good dose of sunshine will be the prevalent mode is uncertain.

 With these rains as noted thus will end the last chance of rain for the state for many days to come, at least for over a week to 10 days.

SATURDAY/SUNDAY: Clearing skies  on Saturday but much cooler with lows in the upper 50Fs to lower  60Fs ; highs in the 70Fs with a westerly wind. 

Sunday will start out also cool but warm to near normal in the afternoon with highs in the lower-mid 80Fs interior and closer to upper 70Fs close to the east coast as winds become more north to north-northeast and weaken.  

True Shower Coverage -Even Thunder - Possible At Long Last

Canaveral Pea Fowl in the scrub

TODAY: At long last after such a dry April (other than a few random showers) we have a 'bona fide' chance for showers, even thunder possible on this first day of May 2017. Granted, no 'drought breakers' are foreseen this week but can't hurt. Only 'threat' might be if a random lightning strike were to hit on parched ground, resulting in brush fire.

Otherwise, increasing deep south to south west flow will import some greater moisture through the lower levels into the mid-atmospheric levels as the day wears on as a front approaches the Florida Panhandle. The greatest chance for thunder is across the panhandle where the SPC (Storm Prediction Center) has outlined a marginal risk for severe weather.  Not sure how well that will pan out at least for the day light hours given the cloud cover over the region at time. Better chance up that way appears to be after dark from near Tallahassee and east along the front itself.

Meanwhile, increasing south to south southwest flow in advance of the front over peninsular Florida..and moisture convergence with ample instability and cooler air aloft should be enough to set off some convergence lines of showers mainly across the east half of the state from Daytona and South as the east coast sea breeze attempts to manifest and press inland. A remote thunderstorm possible, with the better chance of thunder appearing to be for Indian River, St Lucie, Martin, and Palm Beach Counties later in the day, possibly even a stronger one or two.

TONIGHT: As front works south the rain chance might again increase , particularly for Brevard County after midnight and before sunrise. 

TUESDAY: Tuesday might dawn for areas of Brevard / Osceola/Indian River Counties (mainly) with rain showers in the area, though nothing particularly strong, if even thunder. Rain could be occurring in the area up through noon time before the boundary shifts further south. Best chance of shower/thunder going into Tuesday afternoon will again be  Indian River, St Lucie, Martin, Palm Beach Counties and southward to Dade.

WEDNESDAY: Easterly flow with little to no chance of rain much of anywhere but toward the west coast of the state.

THURSDAY/FRIDAY: Another front will approach the area with the better chances of rain it appears to be North half of State, with Central getting its dose on Friday - though will likely need to revisit these days as they get closer.

WEEKEND: Weekend looks dry both days and pleasant with temperatures near normal with lows in the 60Fs and highs in the lower to mid 80Fs southern interior. Continues to look dry for quite some time to come as well.