[nwctwx]

Tornado Watch Effective Until 6pm : Florida

THE NWS STORM PREDICTION CENTER HAS ISSUED A
TORNADO WATCH FOR PORTIONS OF

CENTRAL FLORIDA
COASTAL WATERS

EFFECTIVE THIS SUNDAY MORNING AND EVENING FROM 1040 AM UNTIL 600
PM EST.

TORNADOES...HAIL TO 1 INCH IN DIAMETER...THUNDERSTORM WIND GUSTS
TO 70 MPH...AND DANGEROUS LIGHTNING ARE POSSIBLE IN THESE AREAS.

THE TORNADO WATCH AREA IS APPROXIMATELY ALONG AND 85 STATUTE MILES
NORTH AND SOUTH OF A LINE FROM 15 MILES WEST NORTHWEST OF SARASOTA
FLORIDA TO 15 MILES NORTH NORTHEAST OF MELBOURNE FLORIDA. FOR A
COMPLETE DEPICTION OF THE WATCH SEE THE ASSOCIATED WATCH OUTLINE
UPDATE (WOUS64 KWNS WOU1).

REMEMBER...A TORNADO WATCH MEANS CONDITIONS ARE FAVORABLE FOR
TORNADOES AND SEVERE THUNDERSTORMS IN AND CLOSE TO THE WATCH AREA.
PERSONS IN THESE AREAS SHOULD BE ON THE LOOKOUT FOR THREATENING
WEATHER CONDITIONS AND LISTEN FOR LATER STATEMENTS AND POSSIBLE
WARNINGS.

DISCUSSION...STORMS ARE EXPECTED TO GRADUALLY INCREASE IN INTENSITY
ACROSS CNTRL FL THIS AFTERNOON. BREAKS IN CLOUDS SHOULD ALLOW FOR
SOME SURFACE HEATING OVER S CNTRL FL AND CONTRIBUTE TO MARGINAL
INSTABILITY. ATMOSPHERE IS EXPECTED TO GRADUALLY DESTABILIZE NWD
WITH TIME AS BOUNDARY LIFTS SLOWLY NORTH THROUGH CNTRL FL. STRONG
SHEAR PROFILES WILL SUPPORT SUPERCELLS WITH ISOLATED TORNADOES
POSSIBLE.

[nuconvert]

Lots of snow this year back east, and in Europe, and in Asia.......must be that darn global warming.

[Libertarian4Bush]

BRING. IT. ON.

[Dat Mon]

Thanks for the post, and keep us updated!

I have an important group meeting in Philly scheduled for Tuesday evening, and im wondering if I should be thinking of canceling it now. Problem is...I may not know if this storm will be bad until it is too late.

[billorites]

Meteorologist Larry Cosgrove's thoughts...

WEATHER SUMMARY THROUGH NEXT 72 HOURS

With the American forecast schemes now clearly trending toward earlier predictions on ECMWF, GGEM, and UKMET runs, it is time to deal with the growing storm threat shaping up over TX. The faster rate of development make this matter imperative, since much of what transpires in the U.S. will occur within the next 72 hours. In a nutshell, we have a rare event called triple phasing taking place. A disturbance in the southern branch strengthens, and incorporates energy from the polar jet stream (in this case a shortwave entering ND). This combinant feature, fed by a huge moisture fetch and widespread intense convection, grows to the point where cA values in Canada are pulled into the circulation, and an existing Grand Banks vortex (50/50 Low) is forced to retrogress into the St. Lawrence Valley, in effect being captured by the explosive impulse. This last leg of phasing all three of the existing high level windstreams looks to occur Monday night, after which time the resultant monster gyre will slow down as it approaches LBR, its final destination.

Because the circulation and dynamics with the TX/Gulf States feature will be so strong, low level cold air from a moderately strong cell of high pressure in QC will be drawn as far south as lower Appalachia and the Piedmont. So while the relatively mild temperatures of Saturday may give residents of N GA, W SC, W, C NC and SW VA a false sense of security, the track of the cyclone and the rapid rise in UVVs on Sunday will produce frozen precipitation, with potential for heavy wet snow in the higher elevations. This in-situ type of wedge from cold air damming could give winter-starved Southerners one last shot at snow and ice before the Winter of 2004-2005 slides into history. Further south, FL looks to be hammered by a combination severe weather + excessive rainfall event, with the low and frontal structure passing in very close proximity to the Sunshine State.

Of course the usual question marks are in place concerning the track and rain/snow line of this cyclone. I like to place the surface reflection of a storm along the leading edge of 500MB height falls. The existing blizzard over eastern Canada (with formative cAk vortex) has shifted the mean trough axis to about 75 W Longitude, so any new cyclogenesis will have to proceed to the right of that demarcation. Since the ultimate destination of the phased storm is the QC Eastern Townships, the low moving up the coastline should bend back somewhat to collocate with the new motherlode. This is why I am insisting on a path of deepest pressure falls through RI, MA, and NH into E QC. So while much of the Interstate 95 corridor gets blasted by what appears to be (and should turn out to be!) a blizzard, anyone living to the right of a Guilford CT....Barre VT....Quebec City QC line is going to experience a change to rain.

Two things stand out about this particular system: the phasing aspect AND the convective appearance, with intense UVV and Omega fields showing upon all of the forecast schemes compacted around the low and its inverted trough (linking the circulation with a the vestigial low in the Great Lakes). Sharp vertical transfer will channel cold air to the surface and keep the rain/snow line along the immediate coast, while at the same time produce staggering snowfall rates that will leave heavy accumulations across the Appalachian Mountains and coastal plain. During Monday night, the sudden drop in 500MB heights and added vorticity should make for an excellent display of thundersnow across N MD....N DE....PA....NJ....NY....W CT....W MA....VT. Then as the low takes on vortex characteristics, winds will increase dramatically by Tuesday morning. Lake-effect snow squall generation should maximize under the vast motherlode, which on Day 4 should effectively cover much of the Midwest and Northeast, driving colder air into the Deep South.

Where would I rank the potential of this system? At least in the same category as the January 22 2005 storm, but more likely comparable to such memorable events as March 1962, December 1992, and January 1996. Keep in mind that much of the snow produced will be wet-ratio type, which can greatly affect power transmission and roof integrity.

[SkyPilot]

Thanks for the info. On Friday, people at work were making plans for meetings and events on Monday thru Wed--saying things like:

"Well, let's all get together on Monday afternoon about 5:00pm and discuss this."

I expect it to be a whiteout by then.

[Peach]

A near historic snowstorm in the northeast is a BIG storm. When we lived in New York and Connecticut, we saw lots of big storms, but I don't remember many of them being called historic.

[Mad_Tom_Rackham]

Is it cold enough to snow in southern GA?

[jolie560]

Very heavy,steady rain all day here in Jacksonville. Wind gusts 30-40. Flood-prone areas are already flooded. Power went out briefly this morning. 2:30 pm EST

[Fiddlstix]

[NCjim]

Here is the complete set of maps - caution - not for dial-up!

http://www.easternuswx.com/bb/index.php?s=5cc59a4402c0775d60ab586533fe2745&showtopic=22490

[TBall]

BR and others did not say anything about the possibility of this on Friday. After reading a FR thread on the two scenarios being Tennessee Valley or East Coast I wanted to see the local forecast. All the area predictions I saw called for rain/snow mix and did not even mention the Nor Easter possibility. At least NOAA presented the two possibilities.

[Maelstrom]

Please keep us updated and ping me once in awhile dammit.

I must travel the I-81 corridor extensively Monday morning and Monday afternoon

[Ernest_at_the_Beach]

Sun shine in Southern California today.....but we should get some crdit for our contributions to this storm, part of our storm has to be part of this storm....but at least on the east coast it will be snow....how deep would 9 feet of water be if it were in snow?

[The Mayor]

They are calling for 6 to 10 inches in the Buffalo NY area.

I hope they are wrong!

[Ditter]

The sun is finally out here in Houston. This storm system was a wet one for us. The rough weather moved thru here on Thursday morning and we have had several days of rain.

[sweetliberty]

I don't know how much more of this global warming I can handle.

[farmfriend]

Once in a blue moon, I'm actually glad I live in CA.

[Oorang]

Excellent maps and information, thank you.

[Brad’s Gramma]

From wet and soggy and muddy Southern California, I pray that all of my FRiends on the OTHER side of the country are safe!!