|Preliminary Outlook (for blogging purposes/not official) For Wednesday|
Orange shows thunder chances. Given the cold air aloft, we MIGHT be in for some surprises on Wednesday due to some hail
WEDNESDAY (Image above): Low pressure will be forming along the Northern Gulf Coast near Louisiana. Meanwhile winds SE at the surface but quickly shifting to West in the mid-upper levels. Upper level temperatures are very cold tomorrow, but lack of deep moisture and low level instability could limit storms to the interior whereas showers could end up moving offshore in at least an expanse shown above if not further south. Thunder could roll off shore the east coast from the Canaveral area and north as well, but it seems more certain along convergence boundaries inland.
THURSDAY: Interesting scenario continues to unfold per consecutive GFS model runs. Forecast discussions which address the ECMWF model of which I have no detailed access to are addressing timing differences and issues which could make a world of difference in the forecast in regard to storm intensity; thus, the precursor comment to not go unsaid is that this blog post is based on the GFS model trends over the past 2 1/2 days, which measa generally nearly 9 model runs.
There is a chance that mid-afternoon storms could form and move in along the west coast from Tampa and north, mainly along and north of I-4. Wind fields above the ground will be becoming stronger with increased helicities values as time goes by and upper level support moves in toward and after dark.
Nevertheless, air aloft unusually cold with curving wind profiles and increasing shear could result in some surprisingly strong to severe storms later Wednesday afternoon mainly along and north of I-4 with an isolated one or two yet further south. Such said storms will have no problem moving right along and not die off quickly as would be in the case in the summer.
Otherwise, greater 'wind energy' moves in after 10pm for a possible second surge of activity. Now, it is possible this will end up being an Event Before the Event situation, where the stronger storms end up being earlier, but so far given the winds this does not appear all too likely. If the latter event (if there is two or even one, at all)..there could be a tornado watch issued across the peninsula as deemed necessary as more and more recent forecast information becomes available. So far, there has been consistency of which most highlights in my mind at least an area spanning from near to just north of the Central Dividing line and north for a tornado threat, possibly coming out of storms in the form of broken bow echoes and rotating isolated activity early on.
Later Thursday evening a QLCS Squall Line which is pretty much a fancy acronym for a broken squall line containing some discrete storm cells, could start to form, but again much of this is entirely speculative and likely over-amped on the blog posters part. Instability is lacking, making this a chance for a high shear - low CAPE set up which is difficult one to forecast with as much certainty would there be more instability at play.
Bulk shear is showing up at the lowest levels (unusual for Florida clear up to 20,000 feet at least) accompanied by very respectable upward vertical velocities regardless of the lack of CAPE and low level instability.
Do note, that the Storm Prediction Center is saying very very little about Thursday at this point, so chances are this will be a pre-emptive Strike Out in the forecast game. For now, the pitch hitter is at bat until it is more clear as to how the cards may fall and who's on base.
BEYOND: Rain chances end from NW to SE Friday ending Dead Central by noon but likely sooner and South Florida by mid-late afternoon. Stronger Storms possible mainly South Florida on Friday from late morning through mid-afternoon. After Friday, a drying trend sets in with slightly cooler temperatures but nothing unusual returning to the normal range in the matter of a day or two.