Rains Chances Slowly Increase For Florida...But When?

The BIGGEST Player for much of North America Today through Friday seems to be that big Double Whammy System in the Atlantic Off New England. It is barely moving if at all this morning. We can see in this image the third of three small MCS (Mesoscale Convective Complexes) that moved off the Coast of South Carolina since this morning. These are narrowly missing Florida, and the storms associated with them can be seen on The Weather Channel here in East Central Florida.

CLOSE UP OF THE SYSTEM OFF NEW ENGLAND.
THESE TWO AREAS ARE STAYING IN PLACE...ROTATING
IN PLACE DISCRETELY, WITH THE SOUTHERN ONE ROTATING NORTHWARD AROUND THE LARGER, NORTHERN ONE. NO MODEL SHOWS THESE AS SEPARATE ENTITIES!!

THE THREE MCS COMPLEXES EARLY THIS MORNING. THE MOST SOUTHERN ONE WAS VERY ACTIVE SHORTLY BEFORE I SAVED THIS IMAGE. HIGH PRESSURE JUST TO THE WEST AND OVER WEST FLORIDA IS BLOCKING THESE FROM REACHING THE STATE

TODAY'S VERY SMALL CHANCE OF AN ISOLATED RAIN SHOWER OR MAYBE THUNDER. EAST CENTRAL WOULD BE AFTER 6PM. THE ZIG ZAG LINE IS SUBSIDENCE TO THE WEST OF THE DISTURBANCE THAT IS OFF TO THE EAST, WHICH CAN BE SEEN IN THE FIRST  IMAGE ABOVE BUT NOT IN THIS ONE. LOW PRESSURE NEAR ORLANDO IS THERMALLY INDUCED (FROM HEAT)

SYNOPSIS: Big blocking low pressure system (s) off the New England/Mid-Atlantic Coast and high pressure over the NE Gulf at time, as has been the case the past 48 hours. Little has changed other than that the low pressure area is enlarging. This system is proving to be quite the forecaster's quandary for not only Florida but the Central Plains states today. This will continue to be the case until it moves..somewhere..which should be a bit more south..then east to northeast beginning later Friday as a system in the Central Plains today  finally gives it the boot.  The Central Plains states system will be forced to 'dig' toward the ESE-SE in days ahead, and in turn force the high pressure area near Florida that is creating all of the hot, dry afternoons to move south and east with time. At time, it appears fairly safe to say this process will begin on Friday but that to could change given the now unforecast/unanalyzed strength of the Atlantic System by the models. This system is indirectly affecting forecasts in the Plains as well, making what looked initially to be a very active severe weather day there not 'quite so bad'...but still 'bad'.


TODAY/THURSDAY: Until that time, the best chance of any showers or thunder will be in the areas drawn above, with an outlier on the South Side of Lake Okeechobee.


It is interesting that a lot of the reason we have not had rain is due to warm air in the mid -levels. Per the latest short term model, in disagreement with the other models run this morning, this warm 'cap' is to disappear this afternoon; however, moisture is too meager in general (PWAT too  low) to produce rain. I can tell by looking outside that the warm air aloft hasn't broken down yet over Brevard due to the haze. Perhaps even the short term model was a bit too hasty in removing this 'cap' of warm air.


Would like to add at this point, the for several days now the high pressure was supposed to break down, with some models (all of them) showing increased rain chances starting yesterday or Tuesday. But that low of the NE U.S. Coast is stronger and more stubborn than any model or person for that matter could foresee. Remember in the post two days ago, this possibility was alluded to? It was mentioned in could even end up drifting right over the state. That too, can still happen going into Friday, thus..the chance of no rain is always there until proven otherwise.


How much of glitch in any forecast going into the weekend will this have? Not too much, but the timing will be an issue. Timing, that is, of when the Atlantic System makes a move.


Two boundaries today. 1) a bit of a trough axis will lay across far N. Brevard County today until mid-late afternoon. We'll know when it breaks over East Central at the coast when we gain an on-shore wind component. In the upper levels moisture is slowly working south from far NE Florida and will build up behind this boundary. Another spoke, or boundary, lies further north toward JAX which will move little. Both of these boundaries could act as focal points for a small precipitation  'chance' later today...but the southern one near Brevard will rely on the wind shift..and that would have to happen at just the right time. If it happens too soon the area will be scoured out by subsidence behind the boundary with the land/sea breeze meeting each other over an area further to the NW where the air is too dry after day time heating removes the low level moisture in that area...caveat..with that boundary in place near North Brevard..just enough moisture could accumulate near it. Thus, the rain chance. Anything to form, if the timing is just right, would probably only be a rain shower though unless something very magical occurs beyond the scope of the laws of physics.


The same scenario will likely play out tomorrow as well, but a change will be in progress.


FRIDAY: Based on guidance, Saturday would be a transition time when the Plains system works far enough east to dislodge the high pressure over the NE Gulf. This would allow more moisture to work in, and with cold air aloft and late afternoon seabreeze / land breeze collision to occur along the east coast of the state late in the day. Better chance of thunderstorms on Friday...but isolated. However, forward motion...and more importantly to Florida, the direction of that forward motion owing to whatever the Atlantic System does..will make a big difference for the state down the road to 'recovery'.


SATURDAY/SUNDAY: Given the blocking pattern and it's evil history (for forecasters), the weekend will be interesting to see how it unfolds. COULD be that there will be rounds of rain/thunder chances at just about anytime, favoring the east side but not always. It gets more difficult when it is forecast that the sea breeze on the east coast will no longer develop. There will be cold air aloft and no capping, but lack of a trigger and any low level boundary collisions as well, in the presence of no forecast upper level disturbance could result in just lots of clouds and some showers. On the other hand, any unforeseen disturbance embedded in this "yet to develop pattern' could contain all kinds of little disturbances to generate very strong thunderstorms. At this time, it appears either Saturday or Sunday would be that day. ...keeping in mind that often any kind of blocking pattern is often hastened foreword too quickly by models..so that time frame could very well end up being Monday/Tuesday...or anywhere in between.