"But seeing they could not See; hearing they could not Hear"
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"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".

Friday, July 21, 2017

Larger Rainfall Totals - Heavy Thunderstorms Again - With Some Near Coast

Storm Clouds Loom Over Hickory Tree Road in Osceola County on Thursday.
Vivid Lightning was dead ahead at the time of image
St Cloud in Northern Osceola reported over 2.5" of rain yesterday
TODAY: Looks like a variation of yesterday's theme. KSC sounding came in at around -7.5C at 500mb and a bit cooler at 700Mb at around 7C (from yesterday). With no capping in place and little in dry air up from the surface to 500mb column would except showers to initiate easily once convective triggers are reached by noon time or so (the KSC sounding shows the convective temperature to be 89F for that area), outside of earlier smaller showers that could begin sooner.  There is already plenty of activity across SW Florida progressing slowly eastward.

Low -mid level ridge axis remains suppressed to far South Florida up toward Southern Shore of Okeechobee County today and tomorrow.

As such, steering in the mid-levels is from the WSW at about 10kts but suspect once sea breezes kick in that most storm motion will be dictated by propagation along the sea breezes as they progress inland and then along outflow boundaries / lake breeze mergers until the brew is mixed until there is one big convective mess 'somewhere' over the interior. The slightly better winds aloft today will only lead to further unpredictable storm motions across into areas that haven't already been worked over by earlier storms. The blue area in the image below is a 'guess' of where that might be.  

Biggest hazard again today will be driving in heavy rainfall and the ever present cloud to ground lightning strikes that can occur prior to heavier rainfall onset under billowing cloud tops or even outside of the storms themselves in 'clear air'.

SATURDAY-SUNDAY: For now will clump these two days together as the Song Remains the Same more or less. Only difference might be for a slight decrease in coverage, namely on Sunday, and that steering toward the immediate east coast north of Palm Beach County might increase just a bit; either that or the east coast sea breeze might get pegged closer to the coast if winds at the 925-850mb levels increase more toward 15kts which is being implied as a possibility on both the morning NAM and GFS model runs. Of the two days, Saturday looks to be the day for a Strong Storm potential once again, with decreasing coverage on Sunday.

MONDAY-WEDNESDAY: Main shift from previous thinking is that the ridge axis' remains across South Central toward South Florida for the duration into next week, even into NEXT weekend. That is to say, somewhere across South Central Florida. The pattern seems to favor more and more the east side of the state for mid-late day storms, though there is some drier air that is going to be thrown into the mix. The GFS runs a 'dry slot' across mainly Central or South Central for several days. Inevitably if this is the case, it will mean many areas will remain rain free, but on the other hand some areas along the moisture gradients across South Central and or North Central might see some vigorous updrafts evolve late in the day. 

FAR BEYOND: Just for now and then we can see how things change in the future, the GFS implies this 'drier' period for some areas will remain relatively brief, (maybe 2-4 days) as yet more moisture begins to fill in and steering remains from the WSW-SW. Granted that is too far out in time; just to throw the bait out for now..then we can see how well the models continue to bite on that prospect  in future runs.

TROPICS: Nothing in the tropical realms of concern at this time into the first week of August (at least). Even if something were to form in the Atlantic, given the upcoming pattern :  location of the ridge axis, and winds would not be welcome for a visit to the "Sunshine" State.

Heavy rainfall along SR528 near I95 on Thursday

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