TODAY: Upper trough off the U.S. East coast with Florida along the SW Periphery of said trough, with mid level disturbance dropping along the backside of the trough and across Florida appears could impact parts of South Florida today with a few showers. Otherwise, status quo weather of yore continues, with light on shore winds and afternoon cumulus clouds away from the coast (where subsidence behind the sea breeze front could result in mostly clearer skies). In regard to the above image, the clouds off shore are dropping south. Not seen now was a healthy thunderstorm cluster (Sir-prize!) that dropped south from east of central and all of the state (no longer visible). This was picked up well by the NAM model, which bears as preamble for what it shows tomorrow..at least in theory.
TONIGHT/TOMORROW: Appears the mid-level vorticity/boundary will get locked up toward South Florida and retrograde toward Central late tonight as surface high pressure presses SE of the state, resulting in a E -ESE surface wind by Friday...a bit complicated to explain, but we can suffice it to say that pockets of 'vorticity' (coiled wind energy as noted passing overhead and retrograding) combined with very cold air aloft for this time of year "schould" (choose which word fits best) result in a coastal trough with very reasonable upward extend as high as 10,000 -13,000 ft (as opposed to 2-4000 ft under "normal circumstances" for coastal troughs.).
Convergence in the low-mid levels combined with moisture being tapped into with E-ESE winds along and behind the trough could result in moisture convergence working upward toward 10-15,000 ft along and behind this trough. This (stress 'assumed') moisture combined with the mid-level energy already in place and upward vertical Velocity fields ..most likely along the east side of this trough... could result in showers and maybe even thunder as far north as the Cape by later tomorrow, but more likely from St. Lucie County and South. Most activitiy will occur East of Orlando southward working inland the further South one progresses.
Otherwise, seeing as how this a new manifestation which developed in model guidance during the past 18 hours, this rain chance "~en-masse chance ~" bears watching for a good rainfall total potential if the NAM model runs of the past 12 hours have any merit along the east coast from the Cape and South (although, its track record has been below less than stellar for quite some time now).
Given the cold air aloft and veering (but rather weak) wind profiles...would not be surprised to see worst case coastal waterspout potential popping up somewhere along the east coast some time tomorrow toward the coast. On the other hand, most areas will more than likely see increased cloudiness through noon Saturday at least along and South of I-4.
SATURDAY: Rain chances/clouds diminish mid-morning through afternoon from East Central fairly quickly toward Southwest Florida as the trough washes out and high pressure reigns supreme. No true chance of measurable rainfall (if even) is indicated well into next week after Saturday's 'potential slight chance of showers' when "Bermuda High Syndrome" kicks in, resulting in SE-SSE winds round the clock , day and night prior to the next boundary in question toward later next week.