'Queen of Mean' Irene Backlashes Mid-Atlantic - Florida Toasts

ENHANCED INFRARED IMAGE OF IRENE SUPERIMPOSED WITH WATER VAPOR IMAGE (the reds/oranges/yellows are dry air). Not the abrupt change in dry to moist along the far north side of Irene's "Kingdom")

TODAY: There's no escaping the information related to Hurricane Irene today when turning on the TV. Folks along the Mid-Atlantic Coast through New England are hopefully prepared for what extremely heavy rainfall combined with strong wind, beach erosion, flooding, and power outages, and storm surge offers in their respective areas. The bathymetry of coastal inlets, outlets, bays, points, and islands will have everything to do with which locations are most heavily impacted by storm surge and direct wind. Either way, the rainfall totals will ultimately be highest where the combination of razor sharp  rain streaks occur repeatedly over the same areas - combined with the persistent, broad scale rain shield.  I would not be surprised to see rainfall totals higher than current estimates, especially heading into coastal New England and over and down toward Baltimore Harbor...as Irene will be merging with the frontal boundary and mid-level trough. Those effects have yet to be realized at this point.    The saving grace for residents further inland at this point is that the current track and forecast (as depicted)..is toward the NNE. But for residents in New England it spells "A-B-I-G-D-E-A-L".


LOCALLY: The peripheral effects of Irene are still being sensed over Florida, which is still encased within the broader mid and upper level circulations of Irene's Storm Machine System.  Wind today will remain W-WSW...with high temperatures in the mid-upper 90Fs and high dew-points resulting in heat indices in the 105-115F range if not much higher.(per the officials, the 115F is the writers own doing). 


Personally thinking that along the east side of the state, especially East Central to NE Florida  could well see temperatures over 100F. Anticipating possibly seeing the thermometer warmer than I have ever (that is 101F). Dew-points will be running high as well. The saving grace, it looks a bit 'milky' out there at my place...very thin cirrus could preclude the record break. Believe Vero Beach stands the best chance of seeing an official record be broken at a reporting station...but far and wide, other records could go down..DAB in second perhaps. 


The heat and moisture (at the lowest level), especially over North Central, are reflected well by the instability of the atmosphere which at this moment (analyzed) and later today (forecast) will be extreme, with Convective Available Potential Energy approaching 7000 j2kg2 units and lifted indices nearly -9C. This is extremely unstable..but its usage, if any, is conditional. Temperatures above that layer are not all that cold. If there is no trigger to set the energy off...it's just a powder keg without a match. That will be the case today.  There are some matches within striking distance indicated  on model guidance though (vorticity) ...but even so, with temperatures aloft being only marginally accommodating  precipitation today will be in isolated pockets if it is to occur at all (it is in isolated fashion over South Florida and parts of the Keys right now since some cool air aloft is present).     


The best chance of rain/thunder today is where both moisture in the mid and lower levels can be in place exactly coincident at the time some upper level energy passes over head. Timing of BOTH of these factors is sporadic, and guidance is nearly useless since with ever hourly run the two factors shift around in both location and amount. Thus, it's best to run with low end rain chances..but some folks will likely get wet today. 


The graphic depicts the most likely areas this might transpire any time over South Florida from the  current time and further north heading into the afternoon through dark. Both areas should dry out sufficiently aloft for no rain chance after sunset.

A Shower could occur any where to the south (right) of the green arrow. Thunder could occur South Florida earlier as some remaining cool air aloft is in place. That is forecast to pull out by mid afternoon; however, I've observed bad track records in guidance in regard to arrival and departure of temperature aloft variations. Also shown here, is a batch of showers and thunderstorms that pulled off the East Coast early this morning which are associated with a moisture pocket and energy. Most of this formed off shore. 

SUNDAY/MONDAY: These two days look quite similar, but moisture will increase a bit. Do not expect it will be quite as hot  because there should be more cumulus clouds in the sky to offset any prolonged direct, unadulterated sun beams striking earth.  There is a better chance of rain over the East Half of the state from mainly DAB and south..but JAX area could get in on the game as well.  Most (but not all) activity will form toward the Eastern Interior and move well offshore...most thunder should not occur until this activity has moved offshore, but that is not set in stone.


TUESDAY: Irene's impacts and her 'territory' of bizarre August weather will lose its reign since the storm will now be north of the lower 48. Moving on to conquer new land.  Sea breezes should form by noon but remain fairly close to the coast. Temperatures return to seasonable norms as does thunderstorm coverage. Some storms on Tuesday could be "strong' in anticipation of a departing jet stream streak of winds well overhead aiding in upper level lift combined with sea breeze convergence in the low leve near the east coast  sea breeze boundary.  


WEDNESDAY/FRIDAY: The trough of low pressure that is located north of the state and across the Deep South today will have sunk south and  be broken off, drifting into the North Central Gulf, as high pressure builds in from the west behind it.  Although very diffuse, this boundary could act as a source of mid-level moisture convergence across much of the state.  Winds resume an easterly component but become quite light both aloft and at the ground. One could argue for late morning to noon time showers/thunder near the east coast working west during the afternoon...with more showers possible close to where the trough is hung up, which appears will be close to dead central. The pattern described above might wash out by Friday, by which point we've reached the end of model reliability.


TROPICS: Watching in days to come both the Gulf and Atlantic.  Already indicated, potential for low latitude tropical waves to pass well south of the state through the Western Caribbean  toward the Yucatan. ..keeping in mind...believe that although the cut off 700mb trough mentioned previously over the Gulf might not be depicted in models, experience says that energy associated with it will linger and wait for something to trigger upon...at which point it will be revealed. 


Thus, watch the Gulf and the Bay of Campeche (where the first action could occur).  Also watching the Atlantic along the remnant boundary to  ignite as either a tropical or sub-tropical system as well.  What else could be  rolling across the Atlantic from a tropical wave that rolls of  near the Cape Verdes, abetted by the West African Jet?  Peak of Hurricane Season time.  

Pre-Irene. Two Sky Lords Converse