"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".

Monday, May 6, 2019

Risk of Marginal to Pulse Severe Storms Once Again

TODAY: A few subtle changes from yesterday's premises (that can make a much larger difference in the scheme of things) appears to be underway from what earlier guidance would left one to think.

As referred to the other day, a mid level trough was premised to slide south of Central Florida by this morning leaving much of 'dead Central' just that. Dead to storms today due to it being too dry aloft; however, given the latest actual sounding out of KSC and model trends, such is not the case at all.

There is still sufficient moisture availability as far north as I-4 and it appears that 'nearly' enough will continue to be at play at least into early afternoon that far north.

Model guidance , especially short-term model runs are consistently showing enough surface based instability and moisture to be in place , if not all day, from nearly all of Brevard County south to Dade.

Temperatures aloft are a bit similar to yesterday as far as it being cold enough aloft to perpetrate strong updrafts along with some dry slots to motivate more potent ones, and mid-level lapse rates look to be running perhaps a tad more favorable for storms today to make up for a slight warming at 500mb (20,000 ft). The overall 'areal coverage region wide'  of instability, however, does not appear to be as great.

On the other hand, sea-breeze development up and down the east-coast looks much more likely than it did yesterday with the morning starting out with very light winds at the surface (though westerly all locations). 

The KSC sounding does show 18 kts of WSW winds around 4000 ft, but below that they are less than 10kts which a sea-breeze could over-come, especially after 1pm though it might be a shallow one. The sea breeze front is where the best low level converge can occur initially , thus resulting in upward momentum. Resulting outflow boundaries from earlier activity coming together along with the sea breeze is likely going to be where the real 'threat' will lie (perhaps Southern Brevard, Indian River, St Lucie counties ).

Strongest of storms will not really get going it appears until after 1-2pm, with a convective temperature of 89F. But again, it is where boundary mergers occur a couple hours later that will tell the story in full. Do note that the NWS has mentioned a reference to 'possible funnel clouds' and 'small hail' with the greater threat again today being wind gusts.

There is some question, however, as to how strong activity will be for Central and North Brevard.

 That far north is the area that has been in question in regard to whether it would rain there at all or not today, that is at least (in the bloggers view) until early this morning, and now especially mid-morning it does appear even that far north could see a 'strong storm'. 

One of the short-term models has very emphatically been implying some of the first activity of the day will go up near 'The Cape' and that storm when finally collapsing would send an outflow boundary southward and scour out much of the surrounding arear within 20-30 miles (perhaps)  - despite otherwise favorable conditions.  

On the other hand, if that does not occur then even a region as far north as SR 50 could be in the park for a 'stronger' type storm especially along the US1 corridor from near Port St John southward.

Below is the Blogger's 'Guess with a Stretch" (to include North Brevard or an area north of South Melbourne).  

(NOTE: The official forecast out of the MLB NWS is not calling for any storms today north of Melbourne as of earlier this morning)

For BLOG Purposes Only, Writer's   'Best Guess at 9AM''

Storm Prediction Center's Outlook at 8:00AM

All in all, apart from the above mentioned, the better chance for 'strong' storms will be along the east coast today, with mainly showers some developing into 'thunder' approaching from the west by noon time (first Lake/Polk) counties, for example

Strongest storms will be after 3pm - 6:45pm from Brevard to Dade Counties, with 'enviably' a 'mystery storm' perhaps evolving somewhere in St. Lucie/Martin Counties near Lake Okeechobee for  those so inclined to witness a 'good storm'.

BEYOND: The rest of the week continues to be dry and warm, even much warmer come Friday through the weekend when  the risk of even then, only perhaps an isolated storm could come above, but in general, next weekend looks dry with summer like warmth (but not quite the humidity).

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Sunday, May 5, 2019

Strong Storms Again Possible Today - Not a Good Beach Afternoon

Late Saturday afternoon  of May 4, 2019 facing South toward the Cocoa Beach Pier from Cape Canaveral
Today: Not much change in thinking in regard to today's weather set up and eventual outcome as the day progresses from late morning into mid afternoon.

A similar set up in the atmosphere per surface instability forecasts with a dry layer in the mid levels   combined with similar temperature profiles  aloft are all forecast to be present. Winds aloft today appear to be just a bit stronger,and as such the east coast Sea Breeze particularly north of Vero Beach might not be able to work as far inland as it did yesterday (for example, west of I-95) if at all. Without a sea breeze at all the whole 'forumla' will significantly change (namely the risk of stronger storms , or at least coverage of them, will be greatly reduced).

On the other hand, with the drier air aloft and strong instability at the surface forecast and similar colder air aloft it is again expected we'll see another round of storm activity to progress initially from the west side of the state eastward , mainly south of a line running from Cedar Key (West Coast) to Southern Flagler County (East Coast) southward toward Southern Palm Beach County (even interior Dade).

There is a bit of a 'condition' however in all this, that being any precedent cloud cover could put a bit of a damper on storm strength and/or coverage. All in all, most guidance suggests the most active areas will be  in the area noted below.

Blog Forecast For Most Active Areas

Below is the Official Storm Prediction Center's (SPC) Outlook for the areas most likely to be impacted by the 'Marginal Risk of Severe" storm activity

Inevitably, there will be a variation from yesterday. There were a few 'minimally severe wind reports' yesterday , but the majority of wind reports came in at the 40-45mph range, which is again expected to be the case today in and near the stronger storms . There was also a 1.00" hail report.  The other difference today might be a slightly earlier onset and hence east ward progression of the main storm focus by an hour or so, from yesterday.

MONDAY: Weak mid-level trough and associated surface 'front' and co-located moisture band will be working down the state as the day progresses. The boundary should lie almost directly 'west-east' across the state around 2-3pm tomorrow afternoon . 

Instability looks ample enough for fast moving 'showers' and maybe some thunder, but the storm risk appears at this time to be substantially lower and limited perhaps more to the East Coast south of Ft Pierce. Rain chances however, do exist mainly from near Cape Canaveral or Melbourne southward .

TUESDAY-FRIDAY: East wind will bring drier air and typical morning and afternoon temperatures. Mornings in the lower 70Fs at the coast (60Fs inland) and afternoons in the lower 80Fs (coast) and mid-upper 80Fs inland. There may be a period of time Tuesday and/or Wednesday for some shallow onshore type showers to work toward the coast, but the chance is quite low as things appear this hour of writing.

FRIDAY-SUNDAY: As we work from Friday into the weekend, thunderstorm chances may well return with much warmer temperatures as well, with muggy low-mid 90Fs a possibility over the interior.

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Saturday, May 4, 2019

Chance of Pulse 'Strong/Severe' Storms Today/Sunday

une 6, 2016 from the KSC Visitor's Center
TODAY: Similar temperature/wind regime from yesterday, though suspect it will get warmer today than yesterday with less cloud coverage to start the day. 

Plentiful low - mid level moisture and surface based instability with a near to side-shore 'sea breeze' along the east coast under a prevailing SW-WSW steering flow aloft of about 10 kts (South Central/South) up to at times 23 kts (North Central) could keep the convective train chugging with residual activity after the first thrust of storms manifests lingering toward dark in some areas.

Near to side shore winds combined with outflow boundaries from 'early onset' activity could result in greater low level convergence in the presence of very cool (but not unusually cold) air aloft, combined with per the RAP sounding for KSC (for example) at 4pm of a dry mid level slot , might result in 'small hail' but more certainly wind gusts in the 40+ mph range. There was a 'severe qualified' gust yesterday in activity near Jensen Beach, so would expect a bit more of the same today, if not a bit more active.

As of early today (this writing) , "Prime Time" could commence after 2pm east central as other showery with some thunder activity progresses east ward along the west coast sea breeze, with a collision occurring mainly near to south of I4 around the 4pm time frame. 

Areas that experience 'early onset' (prior  to 4pm) might all out 'escape' any of the stronger activity that would/could have occurred later since those areas would be stabilized by the cooling rains that fall from them (assuming there will be such activity).

Overall 'coverage' of storm activity looks almost certain, mainly for areas over the interior south of I-4. Here is a 'general thunderstorm' coverage outlook generated by the Storm Prediction Center (SPC), located in Norman , Oklahoma.

Back to home, strongest storms will be capable of frequent lightning. small hail, and strong wind gusts in and near the strongest storms. 

Things should begin to wind down in regard to the stronger activity rather quickly after 5:30- 6:30pm, though expect there could be residual pocket of rainfall to continue in some locations.

The bloggers most 'unofficial outlook' (refer to official sources as usual) is to be watching for strong/pulse severe activity in the 'red' area today.

SUNDAY: This day could be just as active (if not more so) as today. 

Early morning model guidance at least 'suggests' that the 'risk' of stronger storms seems to be even greater, for the same general area as today, though extending further northward to cover all of Volusia if not even Flagler Counties.

Granted , this is subject to change as usual, but it does appear to be that at a minimum, we could expect yet another day of a round of storms , but where specifically any one storm will hit with greater impact is as usual indeterminable.

MONDAY: Risk of stronger activity at this stage diminishes greatly as mid level moisture pooling along a mid level trough pulls off the U.S. East coast and slides south toward Lake Okeechobee. 

Temperatures remaining typically warmest inland. 

Coming days look to get quite warm by Wednesday, especially for the interior with wide spread lower and maybe even some mid-90Fs (?); however, as far as rainfall is concerned, mainly 'dry'.

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