"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".

Tuesday, January 4, 2011

Variably Nice Through Mid Day Wednesday

This morning's images first show the averaged mid-upper flow as observed this morning, with the second image showing the 700mb forecast (which is in the mid-levels) for this afternoon. Note that the two images look very similar. Invariably the flow just overhead is from the west, and it's quite moist in a shallow layer around 5000 ft. The first image also shows this moisture content occurring in 'patches', with a more significant consolidation (by the light blue shades) approaching the Florida Panhandle. The last image was included to depict the developing upper level set up described yesterday with impulses ejecting out of the low off Southern California riding eastward and merging with arctic air near Texas. The overall 'mean' track of the two combined is across N. Florida, Alabama, and Georgia through Thursday.

SYNOPSIS: A weak mid-level impulse is currently passing over N. Florida, Georgia, and probably about to already exit Alabama. Some very light rain patches have been noted over N. Florida this morning per radar returns, but much of this is not reaching the ground. Not shown is a very leak low pressure system off the Florida East Coast (east of Ormond Beach) and randomly located high pressure bubbles embedded within the westerly flow just overhead. Meanwhile at the surface over Florida the pattern is much the same (especially from near SR520 and points north), but a generalized weak westerly surface flow will develop today in the wake of the short-wave trough passing to the north of Central Florida. Another way of looking at is, is that the North Half of Florida is setting up for a variety of weather conditions during the next 48-60hrs while South Florida remains south of the trouble makers (for the most part).

TODAY: So what does this all mean for today? We've lost the northerly wind of yesterday, and as expected a weak west wind should be the prevalent mode today. The models are all showing more sun than clouds this afternoon, but I'm not willing to fully bite on that notion. It's safe to say that the majority of the day will be partly cloudy with the majority of atmospheric moisture still in place between a 2800- 5000 ft layer still in place like yesterday and as mentioned above (the level at which the clouds will be today). The high temperature today will consist of widespread mid-70s with upper 70s further south. The 70F degree isotherm will run roughly along the Beach Line toward Tampa, with areas further north of this line in the mid-upper 60s, with the 70s south of that line.

The coolest spot in East Central Florida today will be right along A1A from the 520 Causeway north through Cape Canaveral and up toward Daytona Beach Shores and Ormond Beach. But locally, the Port Canaveral area toward the pads may just eke out a low 70F degree reading -- in short, it'll be close. I mention this only in recognition that it would be nice to make that what has personally become 'the magic number for these parts' .

It's all contingent on the presence (or lack there of) of the pesky on again/ off again stratocumulus deck at the critical peak heating hour of 12-30pm to 2:30pm. These clouds form at the level described above where the most moisture is present aloft. Expect we will see a good cloud break during the late morning, but as is often the case with ample low level moisture in place during this particular synoptic set up during the winter, the heating provided during the 'cloud break' aids only in forming more clouds after an hour or two. But it is safe to saw that the beach side will easily see very close to 70F...ah, who cares really? Who knows, if clouds do not reform as feared, low 70s could be easily realized.

Elsewhere though, despite some clouds, those areas west of the rivers will all be in the mid-70s with upper 70s possible as well in a few spots, most likely over all of South Florida and in patches over the Central portions.

WEDNESDAY: With passage of the short wave to our north today and tonight we could see a northwest wind developing on Wednesday for a time which could also harbor in some ever so slightly drier mid-level air during the afternoon for a brief time. With that notion, despite the more northerly wind tomorrow, the better chance of sunshine will result in temperatures similar to today.

LATE WEDNESDAY: Pretty big overrunning (isentropic lifting type), rain event is just beginning to evolve along the Northern Gulf of Mexico, and will most assuredly become evident during the day Wednesday as a solid rain shield evolves from Southern Mississippi-Alabama and the Florida Panhandle as energy from the low off the California Coast ejects eastward toward that area. Additionally, a surface area of low pressure could form in the North Central Gulf which will ride along the developing boundary and eventually across North Central or North Florida during the day Thursday. The sky conditions by late Wednesday afternoon will gradually deteriorate from Melbourne to Tampa and all points north with lowering cloud ceilings and the chance of rain fall increasing as the fully evolved rain shield sinks south toward SR 528 around midnight. Temperatures will be in the mid 50s as winds back to the WSW and increase to the 10-15mph range into Wednesday night. I'm seeing a chance of thunder on The Weather Channel this morning. Believe the chance will be limited to folks further north.

THURSDAY: Do believe that anyone from Satellite Beach toward Tampa Bay will be waking to light or even periods of moderate rain fall Thursday morning and even more likely at lunch time in advance of the boundary sinking south and evolving into a cold front. Or at a minimum, an overcast sky. The rains could actually start as soon as 11pm -1am time frame overnight (Wednesday into Thursday).

Very cloudy all day Thursday with temperatures hold steady in the 60s, but this is iffy. If the rain falls for a long duration of time, wouldn't be surprised to see high end 50s in a few spots due simply to cooler air aloft being dragged down to the surface (rain cooled air). Thursday looks like a pretty crummy day. How long the chance of rain will last over Central Florida is still questionable in my mind to some degree, but do believe it will be over by mid-late afternoon as the now evolved cold front sinks south only slowly at first without a good push aloft from the northwest as is typically experienced when a big cold air event strikes. Thus, there won't be a sudden change in weather conditions as the fronts continues south.

Behind the boundary temperatures will fall though and stay 'fallen' through Saturday. "Help, I've fallen and I can't Get Up!". The biggest weather story will occur when the low pressure system and energy helping to generate our rains phases with energy out of Canada NNE of Florida near the eastern mid-Atlantic and NE States over the weekend where a widespread snow event will evolve, perpetuated by a combination of Pacific and Gulf Moisture with colder Arctic Air as those two storm tracks merge.

FRIDAY: Someone get her "life alert"! Very cool Friday and Saturday with much improved sky conditions. Interestingly, the last 2 runs of the NAM have shown a little 'cold pocket' near West Central Brevard county (of upper 30s). Don't know what that's all about; just an observation of that model is all. But low 40s for Friday and Saturday with afternoon highs in the upper 50s to low 60s seem to be the status quo at this point (morning model runs have not come out yet, so this could change and will be mentioned in tomorrow's post). The coldest day looks to be Saturday.

And of course, warmer to maybe even much warmer from West Palm Beach to south of Sarasota on the West Coast where they are further away from the zonal, westerly flow and cooler air aloft. This same area will see a significantly less chance of rainfall as well. In essence, South Florida will remain out of the storm track altogether, not to say it won't rain down that way some where though, just not as high of a chance of accumulations with less coverage.

SUNDAY: A warming trend will develop by afternoon as yet another storm impulse approaches from the West (Texas) along the zonal flow aloft over the Southeast states and winds begin to veer completely around to an easterly and eventually southerly component to start next week.

Believe the weather headlines as noted above by late week and into the weekend will concern folks around the east and south side of the Great Lakes due to Lake Effect snows and around the mid-Atlantic States toward the extreme Northeast States. All this will occur as Florida will have long dried out and will be entering the end phase of this brief very cool spell.

In fact, while they are ending or still experiencing their event up that way we'll already be setting up for the next 'close to impossible at this point to forecast' weather event of sorts. Timing and intensity of which at this point is up for grabs. But again, as has been mentioned in several previous posts, even the long range Magic Eight Ball outlooks do not show a very cold spell of freezing temperature potential for Central or South Florida. Would be nice to read "You Will Encounter a Sunny, Warm Stranger" after giving it a good shake, but that is yet to be seen. In essence, a period of below normal temperatures is at hand from Thursday Afternoon through Sunday morning.

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