"But seeing they could not See; hearing they could not Hear"
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"From its chamber comes the whirlwind, and cold from the scattering winds." - Job 37:9.

"The wind blows to the south and turns to the north; round and round it goes, ever returning on its course".

Tuesday, September 20, 2011

Will a 'Caribbean Express' on the Tropical Connection Dampen Weekend Plans?

Sunrise Sea Storm On The Approach This Tuesday Morning, Looking South-southeast from Cape Canaveral 

TODAY: Very little change in thinking required today through Wednesday. Mainly SE winds, light but prevailing from the surface to 10,000 feet over South and Central Florida continue to draw in sporadic atmospheric moisture globs. As anticipated, the east coast (namely Brevard and eventually parts of Volusia and Flagler) got in on the rain act over night through late morning. The Brevard Activity has ended, but not before sending outflow to the west through north, which is generating more activity further from the coastal communities toward I-95 and west.  Expecting most thunder and lightning over the interior today, isolated and possibly becoming a bit more scattered toward late afternoon and dinner time over the interior..mainly from Osceola County and north in the same locations as late yesterday, although more could be found toward I-10 as well. Some stronger storms are possible later today to the far north near Gainesville and west of JAX, although some high clouds on the approach from the west might offset that possibility.

It is up for debate as to whether the west coast sea breeze will be able to from today, or at least in regard to how far that breeze will work east and away from the coast. The pressure gradient at the surface is light through the lower levels, so with daytime heating it should be able to work a good  10 -15 miles inland. The East Coast Sea breeze has started already, but should make less inland progress north of Volusia County. Stronger storms are possible over far North Florida and perhaps toward the SW Coast. 

TONIGHT/WEDNESDAY: Increasing moisture on continuing SE winds (light and variable at the surface overnight) should continue. The diurnal cooling of the land mass overnight in opposition with the now warmest waters most of the east coast sees at this time of year could give rise to more showers and maybe some thunder after midnight, mainly upstream of the North and Central Bahamas where wind current eddies provoke/stir the atmosphere over the warm waters to generate showers. This morning the 'chosen spot' was  eastern Brevard County. Guidance points toward that location again, but the reality is that there is no definitive way to know for sure if there or anywhere will fall victim. My location received over 1.8" of rain between 1AM -11AM this morning.

Downpour around 9:30AM, Accompanied by Thunder

THURSDAY/WEEKEND: Will put this entire frame in one category for the time being.
The frontal boundary alluded to yesterday near the Mississippi River, sure enough as guessed (despite what some guidance had shown), is now no longer forecast to progress beyond NW Florida toward NE Florida for quite some time to come. The parent upper level low is shown by the GFS to nearly cut-off from the main jet stream flow..although in doing so over Lake Superior, it is resupplied by impulses from the Northern Branch Jet Stream from the WNW (Canada)...these impulses or waves of energy evoke the low to Drop toward the SSE over Lake Michigan as the are pulled in and drop down the backside of the low. 

Despite the normal attempts to continue eastward it begins to confront the vast high pressure area that stretches from the far Eastern Atlantic to the United States.  If one is to believe the GFS, this trough is no match for such a might region of high pressure, so instead of moving further east it simply works south with time...with each disturbance feeding in from the back (west) drops yet further south through the Tennessee Valley. As such, the pressure gradient in the mid-upper levels tightens harboring more of a steady SSW flow aloft, while winds at the surface remain much lighter, enough to allow sea breezes each day.  

Meanwhile, as the trough/low drops further south, the "Caribbean Moisture Express" is enhanced further both from the far SW Gulf as well as the south and Central Caribbean.  If again, one is to believe the GFS, then this moisture will feed the whole way up the Eastern Seaboard over  Appalachians toward Maine through Monday next week as a series of impulses exits Florida (perhaps as a result of diurnal afternoon thunderstorm activity over the state) or off the coast of SE Georgia, all commencing sometime around Thursday but much more pronouncedly by Saturday.

Colors are depicting the amount of deep layer moisture. Purple is very high moisture content (necessary to produce rain) whereas the light blue toward the Rockies is very low. This is the forecast of the GFS for Sunday evening. But it continues through early next week. Moisture is being converged or squeezed between high pressure on the far right and low pressure to the west. In this image is also shown some higher moisture dropping into Louisiana/Eastern Texas. That is a reflection of another disturbance dropping south, to eventually join forces with the "Tropical Connection Train" by Tuesday.
 Again, the extended as always is to speak in only very general terms. The next model run will show a variation of this theme...and by the end of the weekend if not much sooner the picture could be quite different. In fact, there might be several variations or completely different conclusions on a continuing basis. The truth can only be revealed as it happens, or at least within a 24-48 time frame. 

 It would not surprise me if even a surface low forms over or near Florida during the course of the weekend. There is  a brief time frame where Florida is shown to be in northerly winds, as perhaps one indeed does form, but then gets scooted up the east coast as some sort of faux warm front.

Flooding might become a big concern for eastern parts of the Mid-Atlantic and west toward Eastern Tennessee and into Virginia before all is said and done if the scenario depicted this morning actually unfolds and comes to fruition.

TROPICS: The tropics are being watched, and there might be an "Ophelia" on the approach in the next couple of days. At this point, it appears any said such storm would have to be either diverted north or continue westward into the Caribbean...and over the Leeward/Windward Islands. If it is diverted north, that would mean a break in the pattern just described above...and anything beyond Monday is completely out-to-lunch on the GFS run of 8AM this morning. 

The rains finally broke this morning

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