"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".

Sunday, January 23, 2011

Rain and Storms (Some Possibly Strong/Severe) Statewide Tuesday - Early Wednesday

Image: Image roughly depicts the temperature regime at 7:45AM this Sunday morning with widespread mid-upper 30s and pockets of freezing west central, totally below freezing NW Central and all North. Warmest along A1A from the Launch pads down A1A to Miami and thru the Keys.

RECAP: Everything unfolded as expected yesterday, with (in my mind) the true cold front right across Central Florida at 1pm yesterday. During that time frame a wind gust of 38mph was recorded on the hour at KSC landing strip with other gusts observed of near equal value at other Central Florida observation locales. The strongest winds occurred along and just behind the leading edge of lowest (driest) dew point air while the base of the mid-level trough and strongest winds aloft rounding it crossed the state.

The same scenario unfolded later in the day further south during the late afternoon and early evening as this boundary continued southbound. With the dry air fully in place across Central Florida by late afternoon and a continuing good dose of NW winds harboring in full cold air advection, the mercury fell in perfect accordance with the setting sun. Winds remained most elevated overnight on the east side of the intracoastal waterway, keeping overnight temperatures from falling much after midnight from KSC and south along A1A. In fact, at sunrise the temperature at Patrick AFB was the same as that monitored at Miami International Airport, 45F. KSC and Canaveral (my porch) both showed a low of 41F, with widespread mid-upper 30s inland. The coldest temperatures South and Central were on the west side of the state (west of Orlando) down to Okeechobee and over toward Punta Gorda (34F both locations).

TODAY: High pressure centers over Southern Georgia northward to Canada will move east during the day but remain generally in firm control over the Florida peninsula today. A north wind today will slowly abate in strength during the day, although we might see a pick up during and just after peak heating as it nearly parallels the coastline. By late afternoon it will most significantly decrease as it slowly veers toward the NE throughout the evening. Skies remain mainly clear, although some stratocumulus could begin to move onshore from Ft. Pierce and south along the coast. It will be cool today with afternoon highs similar to those of yesterday (low 60s) expect far south where it will be cooler than yesterday due to the delayed 'true frontal' passage south of West other words mid 60s down there. Wide spread low -mid 60s should be the rule though, cooler north but not by much until as far north as I-10.

TONIGHT: Light NE-ENE wind overnight will advect higher dew point air temperatures onshore to approach I-95 by daybreak, Monday. This will keep coastal temperatures a good 8 degrees warmer than last night. Pretty quick sunset temperature drop should level off at the coast by 10pm as the now prolonged NE'ly component wind continues to modify mainly the coastal air mass, with a low in the upper 40s there as opposed to much cooler temperatures inland. Frost possible Monday morning North and west of I-4 where the richer dew point air will have permeated and overnight lows will fall into the mid-upper 30s with near calm winds there.

MONDAY: Air mass modification, which to a small degree has already begun this morning will show its true colors during the day in a most uneventful way, namely in the form of higher dewpoints, warmer afternoon temperatures, and some stratocumulus clouds. Low 70s could be realized far south, with mid-60s very close to the coast and upper 60s away from the coast. A few degrees warmer yet from West Palm and south, especially over SW Florida. Winds very light from the ENE-E and partly cloudy. Additionally, an inverted trough along the coast will be setting up very close to the coast from Miami to the Cape, which will strengthen during the afternoon. A shower is possible SE Florida (and models show this to occur as well near the Cape by late afternoon). This might be stretching it a bit though, and will leave it at that there could be periods of enhanced clouds to mostly cloudy conditions periodically...but predominantly partly cloudy.

MONDAY NIGHT-TUESDAY EARLY: Phase two of air mass modification in full swing at sunrise with a warm front developing far South overnight late and located nearly across dead Central Florida at sunrise. SSE winds all day south of this boundary as it heads north through the day toward I-10. Mild overnight temperatures with increasing moisture. Will introduce a small rain chance along the coast as the warm front passes and crosses along the inverted trough which should be located right at the coast from Miami northward with time. Rain chance should disappear for a time from mid-morning to early afternoon while a low pressure system RAPIDLY develops in the northern Gulf south of the mouth of the Mississippi River.

TUESDAY AFTERNOON AND BEYOND: By Tuesday afternoon we continue with a healthy SSE-S wind at the surface with a veering wind profile as one goes up in the atmosphere (more from the SW-W as one goes high up in the atmosphere). This would favor rotating storms by late afternoon but the amount of overall instability is highly debatable, but certainly rain chances increase as a shot of mid-level moisture crosses South and Central Florida as a totally separate entity from the developing storm system which will be ever-evolving in the Northern Gulf. Won't bring in the thunder word at this point, but bears watching. Time to keep advised of the weather though if one hasn't already.

TUESDAY NIGHT: Leaving this period in general discussion mode until the finer details can be ironed out between various models. But the very general consensus is for the weather to go downhill continuously (west coast and north first) spreading east overnight. Low and mid-level winds strengthen to 50+ knots across Central Florida by late afternoon Tuesday, and get stronger in the upper levels over night.

Looks like the peak of any strong/severe activity (if it's going to occur) will happen while it is dark. First on the west side then approaching the east side of the state after midnight. This could occur in at least two waves of activity. Should note that heavy weather will have already been occurring over North Florida for quite some time prior to that over Central Florida, and any outflow boundary generated by that activity further north that works south toward Beach Line Alley (Tampa to Cocoa Beach) could create havoc in not only the timing forecast but also the intensity of storms. It is simply too soon to dig into these intricate details this morning, considering this is still a good 60 hours (at least) away. And we haven't even touched on what could occur over the Loop Current off the west coast during the late afternoon Tuesday into the late evening hours.

Tuesday temperatures will be close to the low 70s (especially south where cloud cover will be less an issue)...regardless, no temperature issues Tuesday anywhere rain or shine. Do believe that at a minimum Central and definitely north Florida which will already be being impacted by heavy rains will see increasing cloudiness during peak heating which will temper down what other would otherwise be a downright pleasant day.

POINT IS: Remain advised on the weather situation during lunch time on Tuesday!! I expect to see lightning strikes over the Panhandle south to the East Central Gulf by that time at a minimum. This is still an evolving forecast situation, and yet to evolve actual one which leaves plenty of room and time for forecast consistency. It's going to come right down to the hour(s) as various ingredients pull together.

The trend has been for favorable wind profiles to evolve which would favor near severe to severe strength wind gusts with one or perhaps two periods of rotating storm structures, so tornadoes are not out of the realm of possibility. Expect that various portions of the state at some time or another will see either a Severe Thunderstorm or Tornado Watch, especially north of a line running from Palm Beach County on the east side toward Sarasota on the west side. An additional fly in the ointment might evolve for Extreme South Florida as well due to even less than obvious reasons than the ones presented at this time than what have been barely hinted at yet. In these situations though, I always watch the Keys toward Miami for an unstable air mass erupting northeastward from off the Yucatan over toward Western Cuba which impacts South Florida/Keys.

I am expecting to see the chance of rain in publicized forecasts for Tuesday go up possibly a couple of times between early today and Tuesday morning. In my mind, the chance of measurable precipitation to occur some time over the entire state is 100% between mid-day Tuesday through Wednesday morning. South Florida and the Keys will be the last to see rain exit the state, perhaps as late as sunset (or later) Wednesday. But Central should be clear of the worst by early-mid morning Wednesday. Don't hold fast to these 'notions' at this time, as they are simply that. But do remain advised at your leisure for the time being.

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