"But seeing they could not See; hearing they could not Hear"
“The views expressed herein are those of the author and do not necessarily represent those of the National Weather Service or affiliate/related organizations. Please consult .gov sites for official information”

"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".

Saturday, June 11, 2011

Chance of Storms (Possibly Strong) Near the Fires In South Florida Today

Not as complicated as it may look to break things down: 1) Low level circulation exists over/near the Central Bahamas (orange arrow shows east Florida on backside of this circulation; 2) Upper level circulation in the Eastern Gulf up to the jet stream level (blue arrow); 3) Expected sea-breeze fronts shown in blue boundaries late today; 4) showers/thunder possible in green and lavender. Image extracted from the Storm Prediction Center's mesoscale analysis page via http;//  with the colored annotations by self

CURRENT: Not much change from the past two for East Central Florida so not much need to elaborate there. There are two 'kind of' interesting features here mid-morning 1) convergent cloud line over far North Brevard over northern Cape Canaveral to KSC has moved little since 8AM. 2) Convergent bands emanating from the back side of the surface low over the Bahamas bringing showers near the coast of Ft. Pierce and vicinity but not quite making it ashore.  Both features will likely dissipate with onset of the East Coast sea-breeze which is a little slow in getting started today due to the disruption on the normal diurnal low level wind cycles in the presence of the surface low as well as the upper level one in the Eastern Gulf.  Mid-level flow flow is weak across the state and a bit dry as well between the low and upper level features. Mid-level moisture is sorely lacking, so not expecting any showers over the land area today here.

"HSD" FORECAST PERCEPTION TODAY: The highlight for the day is hopeful thinking that showers and thunderstorms will form very close to the  persistent fires in Western Miami-Dade area. Smoke had moved in toward the metro area this morning on NW winds which had been directed toward the WSW-W the previous two days.  Under the assumption that thunder can form over  the far South today, this would potentially help quench the thirsty vegetation, although there is also a threat of lightning. Mid-level moisture and winds are lacking, so any storm that can develop in this area could be either an efficient lightning producer or a wind gust maker near the storms. This would be the CON side regarding the fires. That being, should a storm form near the fires, send out dry lightning and be accompanied by strong wind gusts, this would add fuel to the fires rather than abort them.

The other area of interest for showers will be toward interior west and northwest Florida as indicated by the showers (green) color. Late evening low level wind convergence near I-75 could result in some very late afternoon thunder in that area, although that  chance becomes even more questionable.

TOMORROW: Essentially all low pressure features will be moving toward the NNE-NE over the next 24-48 hours, thus Sunday will begin an overhaul (transition) of the atmosphere in the winds fields.  There does appear that there will be a better chance of sea breeze convergence (collision) over South Central and South Florida over the interior. Light mid-level winds and timing (late) of this collision will likely keep the coasts dry on both sides of the state, but there is a chance of isolated thunder over the interior areas to west of I-95 and South Florida once again.

MONDAY/TUESDAY: A stationary front over the country's mid-section and into the NE states (combined with a geographic-type trough down the spine of the Appalachian Chain) will be forced south to southeastward into Central Georgia. By this time, the low currently over the Bahamas will be FAR removed from the picture and possibly merge with the synoptic scale front off the coast of the NE states with time. Overall atmospheric moisture levels will be sufficient for interior thunder again, but mainly closer to the front/trough over North Florida. Finer details, given the mounting uncertainty with time going into this time frame will need to be re-evaluated as this time frame approaches. 

It is interesting though (to this writer), that Tuesday could end up being a day of rather strong thunderstorms over East Central Florida.  Both the NAM and GFS indicate the surface front will be located near Southern Georgia with NNW-NW flow aloft, and from the WNW in the mid-levels ( with a sea breeze).  Mid-upper level energy (vorticity lobes/maxims), are forecast to be embedded within this flow and to enter Central and North Florida during the early - mid afternoon hours.  The net affect would be isolated but strong storms over East Central Florida from the mid-late afternoon reaching the coast by early evening. Worth monitoring. Meanwhile, South Florida might remain once again dry during this time frame.

BEYOND TUESDAY: GFS has shifted gears into over-drive (unfortunately) and wants to bring the front completely through the state by Wednesday, bringing a return to 'east to west' low level flow across the state. This is forecast, per this sudden change, to last until at least early NEXT weekend before a pattern more favorable for seasonable afternoon/evenings showers and thunder can again be introduced into the forecast as it previously had shown to be continuous from Tuesday and points on in previous model runs. I believe this change in the extended is due to the strength o fa system as it gains momentum over the Central Plains states today and tomorrow, which looks to be greater than previously supposed. Not sure I'm buying into the trend just yet.

TROPICS: No tropically inclined features worth note are analyzed this morning. Will be watching the Bay of Campeche area though heading into late next week (personally).

As is noted at the top of the web page for these forecasts, 'all discussions and forecasts are of my own interpretation/extrapolation/best guesses. Please refer to official NWS forecasts".  To add, though, I often read each and every forecast discussion from the offices in Florida as well as others in the Deep South as well as the Plains states to gain a broad perspective of the overall large scale picture. It is interesting to see what others are able to see that I may miss; on the other hand, it sometimes (but rarely) works the other way around.

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