Jump to content

  • Member Statistics

    17,606
    Total Members
    7,904
    Most Online
    ArlyDude
    Newest Member
    ArlyDude
    Joined

Christmas Storm III

Cold Rain

By Cold Rain,
in Southeastern States

Recommended Posts

  • Replies 1.1k
  • Created
  • Last Reply
FoothillsNC

FoothillsNC

Posted
Posted

Its just loony how the Euro keeps getting more and more intense with the phasing. Basically though, my thoughts remain unchanged. As expected, the low has shifted ever so slightly further south (at least initially) so that the heaviest precipitation rates will be felt across eastern NC. Thats not to say areas in the western Carolinas can't get on the action, its simply too early to know for sure how powerful of a system we are dealing with. The degree of phasing is extreme since the euro is essentially dealing with three pieces of energy that will phase together... the timing literally has to be perfect.

wwkriw.png

well I mentioned earlier in the thread why I am a believer in the extreme solution. Its possible because of the extreme NAO we've had, the 3 previous arctic outbreaks attest to a portion of that, and now we have signs on all models of an almost unmatched PNA ridge in western Canada, and to top it off, the ejection of a southern shortwave, which probably remains healthy and closed the entire trip. I've been saying since 3 days ago I think it will stay closed most of the trip, also we have the Newfoundland vortex moving away at just the right time again, on all the models. These are all necessary ingredients for an unprecedented situation here in the Southeast. The blocking has been off the charts 2 weeks or so, and if we truly do get the split flow temporarily and the big PNA ridge (the biggest unknown-- but looks likely), then we can certainly have an extreme solution. Its just that we have never seen all these indices at the exact same time on any one storm for our area. It happens in New England every few years, but probably only once in 100 years for the Southeast. The extremely deep amplification is the key to this I think, and the Euro has been really good lately on the real amplified looks. But its no guarantee of course. Only time will settle this Personally I think the actual surface pressure is underdone off coastal Georgia by a few millibars, given the setup. But looking back at past 1000 mb storms in coastal GA, they've been really good ones here, and thats without the 5H cutting off over the Southern Apps. Its really an unprecedented setup in modern times. I guess we'll see, but if the Euro maintains this look, then someone in the Carolinas is going to get buried. Literally.

One other thing, the QPF is never right over the Upstate, eastern GA and western foothills and piedmont of NC for coastal GA storms I've noticed. There will be an inverted trough stretching back to GSP or AVL region , like all coastal storms, that for some reason the models never show well. This happend last Feb. as well, where the ligght snow continued on for hours and hours here and western NC foothills all due to that feature. So thats part of the reason I take QPF witha grain of salt in a situation like this.

Link to comment
Share on other sites
superjames1992

superjames1992

Posted
Posted

000

FXUS62 KRAH 220810

AFDRAH

AREA FORECAST DISCUSSION

NATIONAL WEATHER SERVICE RALEIGH NC

310 AM EST WED DEC 22 2010

.SYNOPSIS...

A WEAK LOW PRESSURE AREA AND COLD FRONT WILL MOVE EAST ACROSS THE

CAROLINAS TODAY. STRONG AND COLD HIGH PRESSURE WILL THEN BUILD INTO

THE AREA FROM THE NORTHWEST TONIGHT THROUGH FRIDAY.

&&

.NEAR TERM /TODAY AND TONIGHT/...

AS OF 200 AM WEDNESDAY...

LOW TO MID LEVEL WAA ALONG AND IN ADVANCE OF A WEAK SURFACE

TROUGH/LOW CURRENTLY OVER SOUTHERN TN WILL CONTINUE TO PRODUCE

OVERCAST SKIES THROUGH THE EARLY-MID AFTERNOON PERIOD. WHILE WE

COULD SOME SPRINKLES EVERYWHERE ACROSS THE FORECAST AREA...SLIGHTLY

BETTER 1000-70MB SATURATION AND LIFT INVOF OF THE SFC WARM FRONT

WILL GIVE SOUTHERN PORTIONS OF THE CWA A BETTER SHOT OF MEASURING A

HUNDREDTH OF TWO THIS MORNING.

THE SURFACE LOW/TROUGH AND ASSOCIATED WEAK LIFT/CLOUDS WILL

GET KICKED EASTWARD THIS AFTERNOON BY THE SHEARED CLIPPER WAVE

DIVING SOUTHEAST THROUGH THE MID-ATLANTIC REGION. COLD DRY AIR

ADVECTION WILL THEN ENSUE...AIDING IN CLEARING SKIES LATE THIS

AFTERNOON AND INTO THE EVENING.

TEMPERATURE FORECAST IS ACTUALLY QUITE CHALLENGING. MUCH LIKE

YESTERDAY...OVERCAST SKIES FOR MUCH OF THE DAYLIGHT HOURS WILL

INHIBIT INSOLATION. HOWEVER...WESTERN SECTIONS COULD BREAK OUT EARLY

ENOUGH IN THE AFTERNOON THAT TEMPERATURES COULD REBOUND JUST BEFORE

SUNSET...RESULTING IN SOME OF THE WARMEST READINGS ACROSS THE

FORECAST AREA. HIGHS IN THE LOWER TO MID 50S IN THE WEST AND

SOUTHERN SECTIONS. DELAYED CLEARING WILL MAKE A COOLER ACROSS THE

NORTHEAST...WITH HIGH IN THE LOWER TO MID 40S. MUCH COLDER OVERNIGHT

WITH A PERSISTENT 6 TO 8 KT NORTHWESTERLY WIND. OVERNIGHT LOWS IN

THE MID 20S TO LOWER 30S.

&&

.SHORT TERM /THURSDAY AND THURSDAY NIGHT/...

AS OF 200 AM WEDNESDAY...

RENEWED CAA ON THURSDAY AS THE CANADIAN SURFACE HIGH BEGINS TO

EXTEND SOUTHEAST INTO THE REGION. THE DEEP NWLY FLOW BETWEEN THE

CENTRAL US UPPER RIDGE AND CLOSED COLD CYCLONE OVER THE NORTHERN

ATLANTIC MARITIMES...WITH RESULT IN CLEAR/SUNNY SKIES WITH BREEZY NW

WINDS OF 20KTS IN THE AFTERNOON. TEMPERATURES ONCE AGAIN RETURN TO

BELOW NORMAL RANGES...WITH THICKNESSES 25 TO 28 METERS BELOW THE 30

YEAR AVERAGE. HIGHS IN THE LOWER TO MID 40S. OVERNIGHT LOWS IN THE

LOWER TO MID 20S.

&&

.LONG TERM /FRIDAY THROUGH TUESDAY/...

AS OF 300 AM WEDNESDAY...

FRIDAY THROUGH SUNDAY NIGHT...THE OVERALL SYNOPTIC PATTERN CONTINUES

TO HAVE AN UPPER TROUGH ENTERING THE SOUTHERN CA REGION LATE WEDNESDAY

AND MOVING EAST ACROSS THE SOUTH CENTRAL UNITED STATES WHERE IT THEN

PHASES WITH NORTHERN STREAM ENERGY DIVING OUT OF CANADA FRIDAY INTO

SATURDAY. RESULTANT SURFACE CYCLOGENESIS OVER THE NORTHERN GULF

COAST WILL THEN LIFT NORTHEAST SATURDAY INTO SUNDAY ALONG THE

SOUTHEAST COAST. UNCERTAINTY AND MODEL DIFFERENCES ALL REVOLVE

AROUND THE EXACT TRACK OF THE SURFACE LOW...WITH THE ECMWF

CONTINUING TO BE THE SLOWEST (ALTHOUGH THE GFS IS TRENDING SLIGHTLY

SLOWER)AS IT TRACK THE SURFACE LOW ACROSS THE NORTHERN GULF OF

MEXICO BEFORE BOMBING OFF THE CAROLINA COAST ON SUNDAY.

WITH THE TREND TOWARDS THE SLOWER TIMING...MOST OF THE PRECIP IS NOT

EXPECTED UNTIL LATE CHRISTMAS DAY/NIGHT NOW...BUT WILL LEAVE A

SLIGHT CHANCE IN FOR THE NORTHWEST FRIDAY NIGHT AND INTO SATURDAY

DUE TO THE TIMING UNCERTAINTIES. WILL THEN GRADUALLY TREND POPS OUT

OF THE REGION DURING THE DAY ON SUNDAY...ALTHOUGH POPS MAY NEED TO

BE HELD IN LONGER IF THE ECMWF VERIFIES. ADDITIONALLY THE SLOWER

TIMING NOW FAVORS PREDOMINATELY SNOW ACROSS ALL OF CENTRAL NC...WITH

THE GREATEST FORECAST CHALLENGE NOW BEING SNOW ACCUMULATIONS. THIS

WILL HAVE TO MONITORED CLOSELY OVER THE NEXT COUPLE OF DAYS AS THIS

HAS THE POTENTIAL OF BECOMING A SIGNIFICANT SNOW EVENT IF MODELS

CONTINUE TO TREND AS THEY HAVE.

MONDAY AND TUESDAY...COLD AND DRY CONDITIONS ARE EXPECTED DURING

THIS TIME FRAME AS ARCTIC HIGH PRESSURE OVER THE NORTH CENTRAL US

GRADUALLY BUILDS SOUTH INTO THE DEEP SOUTH. THIS WILL RESULT IN

TRANQUIL WEATHER AND WELL BELOW NORMAL TEMPS.

Link to comment
Share on other sites
FoothillsNC

FoothillsNC

Posted
Posted

Hate to be the bearer of bad tidings, but the Op Euro is a big outlier compared to its ensembles- still has a decent event, but much more like the GFS than the Op. Sorry, I think this may easily happen.

I think the use of ensembles is extremely overrated and they continually get misused . There is a reason the Op. model is number 1. I've seen the ensembles outdone many times by the operational GFS and ECMWF. I'm not saying it will happen this time though. The storm could be out to sea barely, this is too close to call or know this far out, even if it had ensemble clustering, we've seen that go the way of the dog many times as well. Nothing is ever a lock in weather.

Link to comment
Share on other sites
POWERSTROKE

POWERSTROKE

Posted
Posted

I think the use of ensembles is extremely overrated and they continually get misused . There is a reason the Op. model is number 1. I've seen the ensembles outdone many times by the operational GFS and ECMWF. I'm not saying it will happen this time though. The storm could be out to sea barely, this is too close to call or know this far out, even if it had ensemble clustering, we've seen that go the way of the dog many times as well. Nothing is ever a lock in weather.

That's why I can't get to excited, been down this road before

Link to comment
Share on other sites
superjames1992

superjames1992

Posted
Posted

PRELIMINARY EXTENDED FORECAST DISCUSSION

NWS HYDROMETEOROLOGICAL PREDICTION CENTER CAMP SPRINGS MD

312 AM EST WED DEC 22 2010

VALID 12Z SUN DEC 26 2010 - 12Z WED DEC 29 2010

...EUROPEAN CENTRE GUIDANCE STAYS THE COURSE ON POWERFUL EAST

COAST STORM DECEMBER 26-27...

WILL STICK WITH THE CONSISTENT ECMWF FOR THE PRELIMINARY FRONTS

AND PRESSURES FOR DAYS 3-7. FOR THREE CONSECUTIVE MODEL

CYCLES...THE DETERMINISTIC ECMWF HAS INDICATED A

MASSIVE...DEEP...SLOW-MOVING CYCLONE HUGGING THE CAROLINA AND MID

ATLANTIC COASTS THE TWO DAYS FOLLOWING CHRISTMAS. THE ECMWF AND

UKMET WERE THE FIRST OF THE GLOBAL NUMERICAL MODELS TO SWITCH FROM

TRACKING THIS WAVE ALONG 40N THROUGH THE MIDWEST...TO A SUPPRESSED

PATH ACROSS THE DEEP SOUTH. SINCE THIS BREAK-AWAY...THE UKMET

SPLIT OFF EVEN FARTHER SOUTH...WITH THE ECMWF LOCKING ONTO AN

EVOLUTION THAT TAKES THE DEVELOPING LOW TO THE FLORIDA PANHANDLE

AND THEN SHARPLY UP THE EASTERN SEABOARD. THE GEM GLOBAL FOLLOWED

THE EUROPEAN CENTRE TRACK ON ITS 00Z/21 RUN...BUT HAS SWUNG THE

SYSTEM OUT WIDER OVER THE ATLANTIC THE LAST TWO RUNS. THE GFS HAS

SHIFTED TO THE SOUTHERN ROUTE ACROSS THE GULF STATES ON ITS

CURRENT RUN...BUT LIKE THE GEM GLOBAL...DIRECTS THE CYCLONE WELL

SOUTH AND EAST OF CAPE HATTERAS. THE ECENS MEMBERS HAVE AVERAGED

CLOSE TO THE DETERMINISTIC ECMWF...WITH MANY MEMBERS FOLLOWING IT

EXACTLY...AND OTHERS TRACKING A BIT FARTHER OFFSHORE. THE

EUROPEAN CENTRE GUIDANCE HAS THE ADVANTAGE IN DEVELOPMENTAL

SYSTEMS WITH ITS HIGH RESOLUTION...AND IS FURTHER AIDED BY ITS

4D-VAR ANALYSIS IN GENERAL. ITS ENSEMBLE MEMBERS ARE MORE HIGHLY

RESOLVED THAN THE GEFS MEMBERS...AND WITH DYNAMIC...DEVELOPMENTAL

SYSTEMS...THE EUROPEAN GUIDANCE SHOULD HAVE THE EDGE.

INDEED...THE GEFS MEAN HAS BEEN CONSISTENTLY FLATTER WITH THE PATH

OF THE BIG STORM...WHICH IS CERTAINLY IN LINE WITH THE LOWER

RESOLUTION. EVEN SO...FOUR 00Z/22 GEFS MEMBERS STILL TRACKED

COMPARABLY TO THE ECMWF...SHOWING A DEEP NOREASTER AND A HIGH

IMPACT STORM FOR THE MAJOR METROPOLITAN AREAS ASTRIDE INTERSTATE

95 FROM WASHINGTON TO BOSTON. TO WIT...THESE GEFS MEMBERS ARE

GOING AGAINST THEIR LOWER RESOLUTION/LESS DEVELOPMENTAL NATURE.

THE ECMWF HAS MUCH CLIMATOLOGY ON ITS SIDE AS WELL...WITH ITS

TRACK WEST OF THE GULF STREAM...AND THE BOMBING PHASE NEAR AND

NORTH OF CAPE HATTERAS.

THE MOST UNUSUAL...AND THREATENING...ASPECT OF THE ECMWF FORECAST

IS THE RELATIVELY LOW LATITUDE AT WHICH THE STORM MATURES AND

STALLS/LOOPS. MORE TYPICALLY...SYSTEMS WILL CLOSE OFF AND HOVER

OVER THE WATERS SOUTH OF NOVA SCOTIA...AS WITH THE MOST RECENT

CYCLONE STILL AFFECTING DOWNEAST MAINE. THE ECMWF SHOWS THE

UPCOMING CIRCULATION COMING TO A HALT JUST EAST OF THE DELMARVA

PENINSULA...WHICH PUTS THE VERY POPULATED AREAS OF THE EASTERN MID

ATLANTIC...LONG ISLAND...AND SOUTHERN NEW ENGLAND IN A PROLONGED

PERIOD OF HIGH WINDS AND HEAVY PRECIPITATION...MOSTLY SNOW. THE

EXTRAORDINARY NEGATIVE NAO THIS MONTH COULD CERTAINLY SUPPORT SUCH

AN ANOMALY. EVEN BEFORE THE RAPID DEEPENING PHASE OF THE

SYSTEM...AREAS OF THE DEEP SOUTH FROM THE INTERIOR GULF COAST

STATES TO GEORGIA AND THE MOUNTAINS AND PIEDMONT OF THE CAROLINAS

MAY SEE A VERY RARE WHITE CHRISTMAS...AGAIN...CONSISTENT WITH THE

REMARKABLE DISRUPTION AT HIGH LATITUDES.

WHILE THE EASTERN VORTEX RELOADS AND EXPANDS...THE FLOW STREAMING

OFF THE PACIFIC WILL BE LARGELY SHUNTED FARTHER NORTH THAN RECENT

DAYS...WITH THE POLAR JET TAKING AIM AT THE WASHINGTON COAST.

SOME FLOW WILL SPLIT INTO THE FAR SOUTHWEST...BUT WITH NOT NEARLY

THE ROBUSTNESS OF THE PAST WEEK.

CISCO

Link to comment
Share on other sites
lilj4425

lilj4425

Posted
Posted

THE ECENS MEMBERS HAVE AVERAGED CLOSE TO THE DETERMINISTIC ECMWF...WITH MANY MEMBERS FOLLOWING IT

EXACTLY...AND OTHERS TRACKING A BIT FARTHER OFFSHORE.

I found this statement from the HPC particularly interesting. I was worried all of the ensembles were against the OP run but apparently they aren't.

Link to comment
Share on other sites
FoothillsNC

FoothillsNC

Posted
Posted

PRELIMINARY EXTENDED FORECAST DISCUSSION

NWS HYDROMETEOROLOGICAL PREDICTION CENTER CAMP SPRINGS MD

312 AM EST WED DEC 22 2010

VALID 12Z SUN DEC 26 2010 - 12Z WED DEC 29 2010

...EUROPEAN CENTRE GUIDANCE STAYS THE COURSE ON POWERFUL EAST

COAST STORM DECEMBER 26-27...

WILL STICK WITH THE CONSISTENT ECMWF FOR THE PRELIMINARY FRONTS

AND PRESSURES FOR DAYS 3-7. FOR THREE CONSECUTIVE MODEL

CYCLES...THE DETERMINISTIC ECMWF HAS INDICATED A

MASSIVE...DEEP...SLOW-MOVING CYCLONE HUGGING THE CAROLINA AND MID

ATLANTIC COASTS THE TWO DAYS FOLLOWING CHRISTMAS. THE ECMWF AND

UKMET WERE THE FIRST OF THE GLOBAL NUMERICAL MODELS TO SWITCH FROM

TRACKING THIS WAVE ALONG 40N THROUGH THE MIDWEST...TO A SUPPRESSED

PATH ACROSS THE DEEP SOUTH. SINCE THIS BREAK-AWAY...THE UKMET

SPLIT OFF EVEN FARTHER SOUTH...WITH THE ECMWF LOCKING ONTO AN

EVOLUTION THAT TAKES THE DEVELOPING LOW TO THE FLORIDA PANHANDLE

AND THEN SHARPLY UP THE EASTERN SEABOARD. THE GEM GLOBAL FOLLOWED

THE EUROPEAN CENTRE TRACK ON ITS 00Z/21 RUN...BUT HAS SWUNG THE

SYSTEM OUT WIDER OVER THE ATLANTIC THE LAST TWO RUNS. THE GFS HAS

SHIFTED TO THE SOUTHERN ROUTE ACROSS THE GULF STATES ON ITS

CURRENT RUN...BUT LIKE THE GEM GLOBAL...DIRECTS THE CYCLONE WELL

SOUTH AND EAST OF CAPE HATTERAS. THE ECENS MEMBERS HAVE AVERAGED

CLOSE TO THE DETERMINISTIC ECMWF...WITH MANY MEMBERS FOLLOWING IT

EXACTLY...AND OTHERS TRACKING A BIT FARTHER OFFSHORE. THE

EUROPEAN CENTRE GUIDANCE HAS THE ADVANTAGE IN DEVELOPMENTAL

SYSTEMS WITH ITS HIGH RESOLUTION...AND IS FURTHER AIDED BY ITS

4D-VAR ANALYSIS IN GENERAL. ITS ENSEMBLE MEMBERS ARE MORE HIGHLY

RESOLVED THAN THE GEFS MEMBERS...AND WITH DYNAMIC...DEVELOPMENTAL

SYSTEMS...THE EUROPEAN GUIDANCE SHOULD HAVE THE EDGE.

INDEED...THE GEFS MEAN HAS BEEN CONSISTENTLY FLATTER WITH THE PATH

OF THE BIG STORM...WHICH IS CERTAINLY IN LINE WITH THE LOWER

RESOLUTION. EVEN SO...FOUR 00Z/22 GEFS MEMBERS STILL TRACKED

COMPARABLY TO THE ECMWF...SHOWING A DEEP NOREASTER AND A HIGH

IMPACT STORM FOR THE MAJOR METROPOLITAN AREAS ASTRIDE INTERSTATE

95 FROM WASHINGTON TO BOSTON. TO WIT...THESE GEFS MEMBERS ARE

GOING AGAINST THEIR LOWER RESOLUTION/LESS DEVELOPMENTAL NATURE.

THE ECMWF HAS MUCH CLIMATOLOGY ON ITS SIDE AS WELL...WITH ITS

TRACK WEST OF THE GULF STREAM...AND THE BOMBING PHASE NEAR AND

NORTH OF CAPE HATTERAS.

THE MOST UNUSUAL...AND THREATENING...ASPECT OF THE ECMWF FORECAST

IS THE RELATIVELY LOW LATITUDE AT WHICH THE STORM MATURES AND

STALLS/LOOPS. MORE TYPICALLY...SYSTEMS WILL CLOSE OFF AND HOVER

OVER THE WATERS SOUTH OF NOVA SCOTIA...AS WITH THE MOST RECENT

CYCLONE STILL AFFECTING DOWNEAST MAINE. THE ECMWF SHOWS THE

UPCOMING CIRCULATION COMING TO A HALT JUST EAST OF THE DELMARVA

PENINSULA...WHICH PUTS THE VERY POPULATED AREAS OF THE EASTERN MID

ATLANTIC...LONG ISLAND...AND SOUTHERN NEW ENGLAND IN A PROLONGED

PERIOD OF HIGH WINDS AND HEAVY PRECIPITATION...MOSTLY SNOW. THE

EXTRAORDINARY NEGATIVE NAO THIS MONTH COULD CERTAINLY SUPPORT SUCH

AN ANOMALY. EVEN BEFORE THE RAPID DEEPENING PHASE OF THE

SYSTEM...AREAS OF THE DEEP SOUTH FROM THE INTERIOR GULF COAST

STATES TO GEORGIA AND THE MOUNTAINS AND PIEDMONT OF THE CAROLINAS

MAY SEE A VERY RARE WHITE CHRISTMAS...AGAIN...CONSISTENT WITH THE

REMARKABLE DISRUPTION AT HIGH LATITUDES.

WHILE THE EASTERN VORTEX RELOADS AND EXPANDS...THE FLOW STREAMING

OFF THE PACIFIC WILL BE LARGELY SHUNTED FARTHER NORTH THAN RECENT

DAYS...WITH THE POLAR JET TAKING AIM AT THE WASHINGTON COAST.

SOME FLOW WILL SPLIT INTO THE FAR SOUTHWEST...BUT WITH NOT NEARLY

THE ROBUSTNESS OF THE PAST WEEK.

CISCO

Year after year our big events go unnoticed to the folks at HPC. I don't think they have ever forecast a big event in the Southeast as long as I've been reading them for atleat 20 years. Whether its flooding or an icestorm, we always take the back seat if any, if the Midatlantic and Northeast is involved in inclement weather. I guess Atlanta, Charlotte, Raleigh, Memphis , Nashville and Jacksonville are small towns? They really need to get out of the same old fashioned line of thinkng that was common 30 plus years ago. A good quarter of those cities' residents have moved down here now. A lesson in demographics is in order at HPC. They're incredibly biased toward that region and shouldn't be since they're the premiere HEMISPHERIC prediction center. The least they could do is cover a potential historic event in the Southeast. Up there with the Weather Channel as far as reliability and responsibility goes, but oh well.

Link to comment
Share on other sites
lilj4425

lilj4425

Posted
Posted

CAE updated AFD:

LONG TERM /FRIDAY NIGHT THROUGH TUESDAY...

MODELS CONTINUE TO INDICATE A THREAT FOR WINTRY PRECIPITATION OVER

THE WEEKEND. LATEST GFS IS TRENDING COLDER AND SLOWER...MORE IN

LINE WITH ECMWF/CANADIAN MODELS. HIGHLY AMPLIFIED UPPER TROUGH IN

THE EASTERN STATES OVER THE WEEKEND. MODELS DEVELOP LOW IN THE

GULF WITH CONSENSUS TRACK EAST-NORTHEAST ACROSS NORTHERN FLORIDA

LATE SATURDAY AND OFF THE SOUTH CAROLINA COAST SUNDAY. PRECIPITATION

TYPE ANALYSIS SUGGESTS UNCERTAINTY BUT A SIGNIFICANT THREAT LATE

SATURDAY/SATURDAY NIGHT FOR WINTRY PRECIPITATION. MODELS SOUNDINGS APPEAR

QUITE COLD WITH ADEQUATE MOISTURE IN SNOW GROWTH ZONE SATURDAY

NIGHT. SNOW APPEARS TO BE THE PREDOMINATE PRECIPITATION TYPE. WILL

INCREASE THREAT FOR WINTRY PRECIPITATION FROM PREVIOUS FORECAST

AND LOWER TEMPERATURES SATURDAY AFTERNOON. MOST OF THE

PRECIPITATION SHOULD END BY 12Z SUNDAY WITH MOISTURE BECOMING

SHALLOW. COLD AND DRY AIR MASS IN PLACE THROUGH REST OF EXTENDED

WITH TEMPERATURES SIGNIFICANTLY BELOW NORMAL THROUGH TUESDAY.

Link to comment
Share on other sites
lilj4425

lilj4425

Posted
Posted

GSP updated AFD and it's a long one:

SHORT TERM /THURSDAY THROUGH SATURDAY NIGHT...

-- Changed Discussion --AS OF 315 AM WEDNESDAY...SOME COMPELLING CHANGES IN MODEL GUIDANCE

POINT TO AN EVENT OF HISTORIC PROPORTIONS OVER THE PIEDMONT OF THE

CAROLINAS FOR CHRISTMAS DAY. THE ECMWF HAS BEEN REMARKABLY

CONSISTENT FOR THE PAST THREE DAYS WITH A SOUTHERN TRACK OF A

DEVELOPING LOW ACROSS THE DEEP SOUTH/NRN GULF COAST ON SATURDAY AND

SATURDAY NIGHT. THE GEM GLOBAL HAS MORE OR LESS BEEN FOLLOWING THAT

LEAD. FINALLY...ON THIS MODEL CYCLE...THE GFS...WHICH HAS BEEN A

FASTER NORTHERN HOLDOUT...IS ON BOARD WITH MOVING THE MAIN LOW

PRESSURE CENTER SLOWLY ALONG THE NORTHERN GULFMEX COAST ON CHRISTMAS

DAY. ON THE ONE HAND...THIS HAS RAISED CONFIDENCE THAT OUR MOSTLY

WHITE FORECAST FOR THE WEEKEND IS ON THE RIGHT TRACK. ON THE OTHER

HAND...CONFIDENCE IN THE GFS IS WEAKENED WITH ITS MAJOR DEPARTURE.

CONFIDENCE WILL GROW FURTHER IF THE OPERATIONAL GFS KEEPS WITH THE

SLOWER SOLUTIONS OF THE ECMWF AND GEM. NO MATTER WHICH MODEL HAS THE

BETTER TRACK...ALL THE MODELS NOW FEATURE PARTIAL THICKNESS VALUES

THAT FAVOR ALL SNOW OVER THE MAJORITY OF THE FORECAST AREA. FORECAST

SOUNDINGS LACK A WARM NOSE...SO IT LOOKS LIKE A RAIN/SNOW PROBLEM.

THE ONLY LOCATIONS THAT WOULD MIX OR CHANGEOVER TO RAIN WOULD BE

ROUGHLY SOUTH OF A LINE FROM HARTWELL TO ANDERSON AND LAURENS. TEMPS

SHOULD BE WELL BELOW THE GUIDANCE WITH THIS SCENARIO. WITH MUCH OF

THE PRECIP TYPE ISSUES OUT OF THE WAY...THE FORECAST BECOMES MORE OF

A TIMING AND QPF PROBLEM...THE GFS STILL BEING 6-12 HOURS FASTER

WITH ONSET BETWEEN MIDNIGHT AND SUNRISE CHRISTMAS DAY. THE SLOWER

ECMWF WOULD HAVE ONSET AFTER SUNRISE TO NOON SATURDAY. WITH THE GFS

ON BOARD...THE FORECAST IS BLEND OF THE GFS AND ECMWF FOR TIMING.

POP RAMPS UP FROM CHANCE TO LIKELY MAINLY SATURDAY MORNING AND

AFTERNOON. IN AN EFFORT TO REIN IN THE EXCITEMENT...THE QPF

GENERALLY FOLLOWS THE LOWER AMOUNTS ON THE GFS...WHICH STILL GIVES

US A UNIFORM 3-5 INCHES OF SNOW ACROSS THE FORECAST AREA SATURDAY

AND SATURDAY NIGHT...WITH THE EXCEPTION OF ELBERT...ABBEVILLE...AND

GREENWOOD COUNTIES THAT STAY ON THE WARM SIDE OF THE RAIN-SNOW LINE.

IT SHOULD BE NOTED THAT THE SLOWER AND STRONGER ECMWF HAS PLENTY OF

SUPPORT FOR ITS SOLUTION. IF THAT MODEL WERE TO VERIFY...WE WOULD

HAVE A MAJOR WINTER STORM MOVING UP THE COAST OF THE CAROLINAS

SATURDAY NIGHT AND SUNDAY...AND THE PIEDMONT WOULD STAND TO GET UP

TO DOUBLE WHAT IS CURRENTLY FORECAST. EITHER WAY...IF WE CONSIDER A

WHITE CHRISTMAS TO BE ONE INCH ACCUMULATION ON CHRISTMAS DAY...THAT

HAS NOT HAPPENED IN THE AREA FROM GREENVILLE (1963) TO CHARLOTTE

(1947) IN NEARLY 50 TO 60 YEARS. IF THIS FORECAST WORKS OUT...IT

COULD BE AN EVENT THAT WILL BE TALKED ABOUT FOR THE REST OF OUR

LIVES. THE POTENTIAL DOWNFALL WOULD BE IF THE SYSTEM SLOWS DOWN EVEN

MORE...IN WHICH CASE THE BULK OF THE SNOW WOULD FALL ON SUNDAY. STAY

TUNED!

IN THE MEAN TIME...WE HAVE A RELATIVELY QUIET PERIOD THURSDAY INTO

FRIDAY AS UPPER RIDGING SUPPORTS HIGH PRESSURE RIDGING DOWN FROM THE

NW WITH COLDER AIR FILTERING IN AHEAD OF OUR DEVELOPING STORM. KEPT

THE FORECAST AREA DRY THROUGH FRIDAY EVENING WITH TEMPS CLOSE TO A

BLEND OF THE GUIDANCE.-- End Changed Discussion --

Link to comment
Share on other sites
HKY_WX

HKY_WX

Posted
Posted

just woke up. wow euro kills everyone, especially rdu. this run would probably be 12-18 for hky-clt and 20-30 for rdu. most of hky precip falls w/ 850's below -5. ratios would likely be .15 to .2 in the western part of the state and .1 to .15 in eastern areas. unreal

Link to comment
Share on other sites
Shep1478

Shep1478

Posted
Posted

And it's only Wednesday..

SPECIAL WEATHER STATEMENT NATIONAL WEATHER SERVICE PEACHTREE CITY GA359 AM EST WED DEC 22 2010

GAZ001>009-011>016-019>025-027-030>039-041>062-066>076-078>086-089>098-102>113-222100-DADE-WALKER-CATOOSA-WHITFIELD-MURRAY-FANNIN-GILMER-UNION-TOWNS-CHATTOOGA-GORDON-PICKENS-DAWSON-LUMPKIN-WHITE-FLOYD-BARTOW-CHEROKEE-FORSYTH-HALL-BANKS-JACKSON-MADISON-POLK-PAULDING-COBB-NORTH FULTON-GWINNETT-BARROW-CLARKE-OCONEE-OGLETHORPE-WILKES-HARALSON-CARROLL-DOUGLAS-SOUTH FULTON-DEKALB-ROCKDALE-WALTON-NEWTON-MORGAN-GREENE-TALIAFERRO-HEARD-COWETA-FAYETTE-CLAYTON-SPALDING-HENRY-BUTTS-JASPER-PUTNAM-HANCOCK-WARREN-TROUP-MERIWETHER-PIKE-UPSON-LAMAR-MONROE-JONES-BALDWIN-WASHINGTON-GLASCOCK-JEFFERSON-HARRIS-TALBOT-TAYLOR-CRAWFORD-BIBB-TWIGGS-WILKINSON-JOHNSON-EMANUEL-MUSCOGEE-CHATTAHOOCHEE-MARION-SCHLEY-MACON-PEACH-HOUSTON-BLECKLEY-LAURENS-TREUTLEN-STEWART-WEBSTER-SUMTER-DOOLY-CRISP-PULASKI-WILCOX-DODGE-TELFAIR-WHEELER-MONTGOMERY-TOOMBS-

359 AM EST WED DEC 22 2010...

A WINTRY MIX POSSIBLE ON CHRISTMAS DAY FOR NORTH AND CENTRAL GEORGIA...A STRONG STORM SYSTEM CURRENTLY MOVING ACROSS SOUTHERN CALIFORNIAAND THE DESERT SOUTHWEST...WILL MOVE INTO THE SOUTHERN PLAINSFRIDAY...AND ACROSS THE DEEP SOUTH SATURDAY SPREADING A WINTRY MIXACROSS MUCH OF NORTH AND CENTRAL GEORGIA.AT THIS TIME ALL COMPUTER MODELS ARE DEVELOPING A SURFACE LOW OVERTHE NORTHERN GULF OF MEXICO FRIDAY NIGHT AND CHRISTMASDAY...MOVING ACROSS NORTH FLORIDA AND INTO THE ATLANTIC BY SUNDAYMORNING. THIS WILL SPREAD MOISTURE INTO THE STATE BEGINNING LATEFRIDAY NIGHT AND CHRISTMAS DAY...ENDING LATE SATURDAY NIGHT.

IF THIS CURRENT FORECAST TRACK HOLDS...THERE WILL BE ENOUGH COLD AIRIN PLACE THAT THE PRECIPITATION WILL FALL AS A MIX OF RAIN ANDSNOW AS FAR SOUTH AS ATLANTA AND GAINESVILLE ON CHRISTMASDAY...AND INTO CENTRAL GEORGIA SATURDAY EVENING. ACROSS THE NORTHGEORGIA MOUNTAINS THE PRECIPITATION COULD BE ALL SNOW WITHACCUMULATIONS POSSIBLE.ANYONE PLANNING TRAVEL ON CHRISTMAS DAY ACROSS GEORGIA...OR THESOUTHEAST UNITED STATES SHOULD KEEP ABREAST TO THE LATEST FORECASTON THIS DEVELOPING STORM SYSTEM.

Link to comment
Share on other sites

Archived

This topic is now archived and is closed to further replies.

Guest
This topic is now closed to further replies.
Go to topic listing

  • Recently Browsing   0 members

    • No registered users viewing this page.
×
×
  • Create New...