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.
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