Winter Weather in the deep south thread

[Ed Mahmoud]

Away from bodies of water, the 850 mb (about 1500 meters) freezing line is usually an approximation of where the rain/snow line will be, and with low humidity and light winds, morning lows will usually get close to the 850 mb temperature, sometimes even cooler.



But not on a small island surrounded by 20ºC or warmer water.


Even with the cooler waters offshore Texas, when IAH is having a freeze, GLS is often in the low to mid 40s.

[boca]

Away from bodies of water, the 850 mb (about 1500 meters) freezing line is usually an approximation of where the rain/snow line will be, and with low humidity and light winds, morning lows will usually get close to the 850 mb temperature, sometimes even cooler.



But not on a small island surrounded by 20ºC or warmer water.


Even with the cooler waters offshore Texas, when IAH is having a freeze, GLS is often in the low to mid 40s.

Thanks Ed I'm up on tropical weather not winter weather since winter weather doesn't really affect South Florida except for once in a blue moon.

[DESTRUCTION5]

The 850 0 line is south of the Keys again.I'm new at winter weather isotherms temps so what does that mean as far as tempature is for Florida.
http://www.nco.ncep.noaa.gov/pmb/nwprod ... p_162m.gif

Snow in Key west! LOL WOHOO!!!

[Ed Mahmoud]

The 850 0 line is south of the Keys again.I'm new at winter weather isotherms temps so what does that mean as far as tempature is for Florida.
http://www.nco.ncep.noaa.gov/pmb/nwprod ... p_162m.gif

Snow in Key west! LOL WOHOO!!!

Well, it would be snowing a few thousand feet above Key West...

And that is assuming some of that light six hour precip was still falling...

[JonathanBelles]

http://www.nco.ncep.noaa.gov/pmb/nwprod ... n_162l.gif

This is what it would look like at the surface.

[Extremeweatherguy]

Well, I don't want to get anyone too upset, but according to JB, this will likely be the coldest airmass of the entire winter from Mississippi eastward. He could be wrong though, so there is still some hope left for you guys in the southeast that want a cold winter!

[MGC]

With a solid two months to go for winter, I doubt this will be the coldest of the winter. Looks like we might get down into the upper 20's with this cold shot. A typical winter here on the MGC sees a couple of mornings in the mid 20's so this is nothing unusual.....MGC

[Sean in New Orleans]

I remember several occasions in my life where New Orleans got into the mid and upper teens. I clearly remember one time hearing Slidell was 8F. That is the real cold stuff...the frigid stuff. No signs of that with this front. Seems like typical Winter cold spell.

[Brent]

Well, I don't want to get anyone too upset, but according to JB, this will likely be the coldest airmass of the entire winter from Mississippi eastward. He could be wrong though, so there is still some hope left for you guys in the southeast that want a cold winter!

I think it will be the coldest of the entire winter, but that's kind of disappointing, because it's only going to last 2-3 days and it looks like there will be no moisture.

Typical cold snap down here, not anything earth-shattering.

[CajunMama]

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LAKE CHARLES LA
340 AM CST THU DEC 27 2007


...THE FIRST FRONT HAS MORE PACIFIC AIR WITH
IT...HOWEVER A SECOND SURGE OF COLD AIR WILL MOVE THROUGH TUESDAY
AND THIS WILL LIKELY BRING THE COLDEST TEMPERATURES OF THE SEASON
TO THE AREA...

Conservative lake charles nws thinks it'll be cold too.

[Cyclone1]

Well, I don't want to get anyone too upset, but according to JB, this will likely be the coldest airmass of the entire winter from Mississippi eastward. He could be wrong though, so there is still some hope left for you guys in the southeast that want a cold winter!

Meh. It's La Nina, (and well, it's the South). None of us really expected a freeze out. Maybe next El Nino...

[Ivanhater]

Dont want to get anyone too excited but 18z is rolling in out to 114 hrs and moisture has returned on the gulf coast....

[Brent]

Dont want to get anyone too excited but 18z is rolling in out to 114 hrs and moisture has returned on the gulf coast....

South of the freezing line of course.

[Ivanhater]

True..but I it all depends how fast the gfs bumps the moisture out before the arctic air comes in...still far out for timing of the precip...

[Lowpressure]

Looks to be dated for the 1st. Cold grips in better during the 2-3-4 timeframe, we will see. Moisture would be nice.

[VoodooCadillac]

Granted - we're a very limited, "special" case, and not in the deep south, but here's the snow (from NWS Asheville):

AS OF 315 AM FRIDAY...THE MAIN FEATURE OF THE MEDIUM RANGE FORECAST
IS THE POTENTIAL FOR A BLOCKBUSTER NORTHWEST FLOW SNOWFALL EVENT DURING
THE MIDDLE OF NEXT WEEK. OVERALL...00Z/28 RUNS OF THE GFS AND ECMWF
ARE IN GOOD AGREEMENT ON THE SYNOPTIC PATTERN EVOLUTION FROM MONDAY
THROUGH FRIDAY. THE TROUGH AFFECTING THE REGION SUNDAY NIGHT QUICKLY
PUSHES OFF THE EAST COAST...TAKING WITH IT THE SURFACE CYCLONE. RAIN
CHANCES DRY UP QUICKLY SUNDAY NIGHT INTO EARLY MONDAY AS BEST LIFT
AND MOISTURE EXIT STAGE RIGHT. DO CARRY SOME LINGERING CHANCE
POPS...MAINLY IN THE EAST IN THE 00-06Z TIME FRAME MONDAY.

THE MOST INTERESTING PORTION OF THE FORECAST TAKES SHAPE TUESDAY
THROUGH THURSDAY. THE MOST RECENT MODELS RUNS PORTRAY ALL OF THE
INGREDIENTS FOR A HIGH IMPACT NORTHWEST FLOW SNOWFALL EVENT. A
CLIPPER TYPE LOW DEVELOPS AND MOVES EASTWARD ACROSS THE GREAT LAKES
ON TUESDAY...PUSHING A WEAK COLD FRONT THROUGH THE FORECAST AREA.
BEHIND IT...H85 TEMPS BEGIN FALLING BELOW 0C AFTER 12Z TUESDAY. GFS
SHOWS H85 TEMPS GETTING AS LOW AS -18C BY 06Z THURSDAY ACROSS THE NC
MOUNTAINS. LOW LEVEL MOISTURE IMPINGES ON WESTERN CAROLINAS ON
TUESDAY AND REMAINS IN PLACE THROUGH THURSDAY MORNING. LOW LEVEL NW
WINDS AND MOISTURE MAXIMIZE WEDNESDAY AND WEDNESDAY NIGHT...MAKING
THIS THE PRIME PERIOD FOR SNOWFALL. CROSS SECTIONS TAKEN FROM OFF
THE TIP OF LAKE MICHIGAN TO THE NC MOUNTAINS SHOW THE TOP OF THE
MOIST LAYER REACHING -30C WEDNESDAY AFTERNOON...WHICH IS WELL INTO
THE DENDRITIC CRYSTAL GROWTH LAYER. MODEL SOUNDINGS ALONG THE
TENNESSEE BORDER ALSO SHOW 25-50 J/KG OF CAPE ON WEDNESDAY WHICH
WOULD SUPPORT CONVECTIVE NATURE OF SNOW SHOWERS AND SOME BURSTS OF
HEAVY SNOW. ALSO...ORIENTATION OF ISOBARS CREATES A BACKWARD
TRAJECTORY POTENTIAL THAT WOULD BE CONDUCIVE FOR A GREAT LAKES
INFLUENCE AND ENHANCEMENT OF SNOWFALL ACROSS THE AREA. I HAVENT EVEN
MENTIONED THE COLD AIR YET...WHICH IS VERY IMPRESSIVE. IF YOU HAD TO
MAKE A LIST OF THE INGREDIENTS FOR A BIG NORTHWEST FLOW SNOW
EVENT...THE CURRENT MODEL RUNS PORTRAY THEM ALL.

LOW LEVEL MOISTURE RETREATS NORTHEASTWARD ON THURSDAY AS A STRONG
SURFACE HIGH BUILDS IN FROM THE WEST. HIGHEST POPS ARE IN PLACE
WEDNESDAY AND WEDNESDAY NIGHT. CURRENTLY...THIS EVENT LOOKS AS
THOUGH IT IS EASILY CAPABLE OF PRODUCING WARNING CRITERIA SNOWFALL
ACROSS MUCH OF THE NC MOUNTAINS.-- End Changed Discussion --

In the last half-dozen years, this type event (described above) has been our only reliable source of snow.

It's been years since we've had a significant storm originate in the Gulf and take the traditional southeast track that used to give us our biggest snows. Granted - those storms still occur, but it's so warm it ends up being a rain, or freezing rain event instead of snow.

What's described above can easily yield 12+" of snow on the NC/TN border mountain areas and 2-3" in the Asheville urban area - and nothing outside the mounatins.

[Lowpressure]

I know, and in living in Charlotte, we will probably see nothing. Or at best occassional snow showers.

[JonathanBelles]

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE TAMPA BAY RUSKIN FL
529 AM EST FRI DEC 28 2007

FLZ039-042-043-048>052-055>057-060>062-065-282230-
LEVY-CITRUS-SUMTER-HERNANDO-PASCO-PINELLAS-HILLSBOROUGH-POLK-
MANATEE-HARDEE-HIGHLANDS-SARASOTA-DE SOTO-CHARLOTTE-LEE-
529 AM EST FRI DEC 28 2007

...EXCESSIVE COLD IMPACT...
A STRONG COLD FRONT IS EXPECTED TO MOVE ACROSS THE REGION MONDAY NIGHT
OR TUESDAY USHERING IN MUCH COLDER AIR. AT THIS TIME THE POTENTIAL
EXIST FOR WIDESPREAD FREEZING TEMPERATURES ACROSS THE NATURE COAST
SOUTHWARD INTO INLAND PORTIONS OF CENTRAL FLORIDA DURING THE
MIDDLE OF NEXT WEEK.

[DESTRUCTION5]

Ocean effect snow on E Coast of FL? Ive seen this a few times...cold!!!

http://www.nco.ncep.noaa.gov/pmb/nwprod ... p_144l.gif

[Lowpressure]

Ocean effect snow on E Coast of FL? Ive seen this a few times...cold!!!

http://www.nco.ncep.noaa.gov/pmb/nwprod ... p_144l.gif

DESTRUCTIONS, You are correct
Living in Jacksonville several years 5-6 ago, I remember snow in Daytona Beach- ocean effect.