"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".

Friday, November 4, 2011

Cold Front Clears State Tonight, Nor'Easter Conditions Through Monday

NOW at 7:15AM - Cold front progressing down the state with rain showers over the Tampa Area to Jax and into Ormond Beach near Daytona. Increasing clouds precede and accompany the cold front which have entered the Orlando Area while the Cape Area remains clear at sunrise.. Est'd front positions and times of those positions in dashed lines.
Showers will become less likely the further south the front progresses, most likely along the Gulf Coast Side toward Ft. Myers with some lighter drizzle like rain occurring on and just behind the boundary from Central To South Florida  

TODAY: A cold front is working down the peninsula from NW to SE with temperatures in the Panhandle in the 40Fs. Preceding the front, temperatures along the immediate east coast are cooler than the past few days as expected given the loss of the onshore wind component which blew across Atlantic water temperatures in the 70Fs. Temperatures this morning south of the front are generally in the mid-upper 60Fs, although some lower 60Fs are being observed west of US1.

The front should cross the Beach-Line toward the east coast between 11:30am to 1:30pm and be accompanied by mostly cloudy sky conditions, and some patches of drizzle. Skies will begin to clear up in this area from Orlando and east after 2pm, with partly cloudy to scattered clouds working toward late afternoon with some better clearing after 5:30pm, whereas South Florida should then be in whatever cloud cover the front can still muster up.

Temperatures today across Central will top out in the lower 70Fs due to cloud cover preceding the front during peak heating hours whereas far South Florida could work into the low-mid 80Fs in Dade, Collier, Broward, and lower Palm Beach Counties. SW winds precede the front and WNW-NW winds follow in the 10-18mph range.

TONIGHT: Front will have cleared the state, and expect a fairly rapid temperature drop as the sun goes down everywhere behind the front, mainly Central and North Florida with clearing skies and lessening winds which will be gradually veering to the NW-NNW overnight. Temperatures falling into the low-mid 60Fs by 8pm Central and colder north Florida.  Temperatures along A1A will likely bottom out around 4-5AM and hold steady right near 60F but much cooler west of the intracoastals the entire East Coast with lows falling into the upper 40Fs west side of Orlando and South to interior SW Florida with a broad expanse of of mid 50Fs toward Miami Metro and Ft. Lauderdale. In essence, nothing has changed from the expected in yesterday's post.

SATURDAY: The surface low accompanying this front will be moving off the South Carolina Coast and be sliding slowly toward the ESE-SE through the day. Florida will be on the backwash side of the developing low and on the front end of high pressure building into the Mid-Atlantic and NE States behind the frontal boundary. Increasing NNE-NE winds by Mid Afternoon with a chances of sprinkles right along the coast with increasing winds in the 18-27mph range from Ft. Pierce to JAX. Here is the GFS representation of this scenario per its 2AM EDT Model Run.

SATURDAY at 2AM. Sprinkles possible at the coast, but mostly expecting cloudy skies. Low that is shown will drop SSE-S another 100 miles at most and remain nearly stationary through Sunday

SATURDAY NIGHT: The GFS is very consistent from run to run, and although it varies slightly with the ECMWF well offshore, the impacts to Florida are not really all that significantly different to bother going into a description on how they differ. The NAM is again most aggressive with the wind fields showing a near gale at the coast. It also shows only specific areas to get rain fall, while most areas are dry. For the most part, Saturday looks dry except that pesky field of very light rain at the coast depicted by the GFS, which looks more to me like mist, especially since the forecast sounding reflects some slightly drier air at the 1000 ft level. Any rain to fall from the already shallow deck of moisture (dry above 6500 ft) will have to do so through winds of 25-40 kts before reaching the ground. Chances are, it will be dry on Saturday until after dark.

SET THE CLOCKS BACK ONE HOUR. We begin Daylight Wasting Time.

Despite the stronger winds at the coast and up through 5000 ft, they will decouple quickly at night, thus inland winds will become more northerly, drainage type with cool over night temperatures , but not quite as cool as Saturday morning. Each morning becomes slowly warmer, and winds decouple again Sunday night into Monday.

SUNDAY: The strongest winds appear will occur late Saturday afternoon and again on Sunday during the late morning through late afternoon. Sprinkles or mist could turn to showers for a time Sunday afternoon with winds at the coast in the 18-27mph range, although winds just above the deck could be a bit stronger. This still needs better confirmation though, since the potential is there for winds in the 32mph range (at least) which is getting to the 'very breezy' to windy level. Showers could occur up and down the entire east coast on Sunday as the low drops to its lowest southern latitude well offshore , which could spread into the interior during the course of the noon-5pm time frame. Highs in the lower-mid 70Fs, perhaps a bit warmer toward South Florida.

SUNDAY NIGHT: Winds decouple once again, with more northerly type winds of 4-8mph over the interior (west of I-95) while coastal winds remain NE-ENE at 12-18mph with overnight lows in the lower to mid 70Fs right at the beaches and cooling by 10F degrees further inland with the drainage flow. Mist or light showers still possible, but again...have an inkling to hedge toward only cloudy.

MONDAY-WEDNESDAY: Winds gradually will decrease for good not until Tuesday night with sunset, predominately in the 18-24mph range at the coast with shower sprinkles again penetrating inland during the day once winds 'recouple' with the stronger 2000 ft level winds after sunrise and spread to the west during the late morning. There could be a time frame when winds become more ENE but those will start to back more toward the NNE to even N on Wednesday as the low pressure area starts to fill and lift north.

The latest GFS has one new twist. Better rain chances along the east coast on Wednesday as the low opens up and allows deeper back wash moisture to back into the coast rather than be wrapped around the low while it was more tightly wound. Meanwhile, another cold front will be approaching the state which puts a quick end to the rain chances later Wednesday afternoon with decreasing winds (which will have already been noted by Tuesday night).

The low off the coast will be stuck in a very progressive split jet stream flow pattern over the U.S., but will act as a bit of a block out at sea. Eventually, the block will break and the progressive pattern will affect Florida as well heading into Thursday.

***NOTE: During the course of this Nor'Easter like event, winds will have a very LONG FETCH off the NW Atlantic. Seas could build well offshore with extra high tides which could cause some minor beach erosion issues in some locations. Needed to say, rip currents and rough seas will be a big boating and swimming hazard, although not sure why anyone would want to go in the ocean to swim under the cloud cover and 'not so warm' temperatures in the 70Fs...with equal ocean temps. Tourist beware. This could make for some good "Victory At Sea" surfing for the experienced who don't mind a strong drift down the coast. I always preferred heading out at one location and not fighting the drift, with someone to pick me up 5 miles down the coast a few hours later.

BEYOND: Very progressive pattern indicating TWO fronts to impact the state Thursday and again toward the end of the weekend. Best rain chance is with the first front on Thursday afternoon and evening.

Winds oddly enough never even get southerly preceding the next front, but instead back to N to NW-WNW-W as the low off the coast lifts north and the next front moves in. The GFS last night had a big cold shot of air with this front taking temperatures in the 40Fs almost state wide (  which seemed suspicious this far out in time since the GFS has a history of over estimating low temperatures beyond 120 hours). Sure enough, the newer run is no longer showing air that cold, and suspect the next run will be even warmer. Very progressive pattern continues with a strong southern branch jet of 100 kts across Florida and an equally strong branch just to the north of the state (but how far north is the great unknown). 

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