Area Forecast Discussion
Issued by NWS Charleston, WV

Current Version | Previous Version | Graphics & Text | Print | Product List | Glossary Off
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50
-- Remove Highlighting --
-- Discussion containing changed information from previous version are highlighted. --
000 FXUS61 KRLX 141902 AFDRLX AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE CHARLESTON WV 202 PM EST SUN FEB 14 2016 .SYNOPSIS... COMPLEX SYSTEM OVERRUNS SLOWLY EXITING ARCTIC AIR TODAY THROUGH MONDAY...FOR A MESSY CONCOCTION OF WINTRY WEATHER THEN WATER CONCERNS. THE SYSTEM EXITS EARLY TUESDAY...FOLLOWED BY ANOTHER TUESDAY NIGHT. && .NEAR TERM /THROUGH MONDAY/... PNS POSTED ON THE COLDEST TEMPERATURES AT DAWN SUNDAY. GLAD WE WENT COLDER THAN GUIDANCE THE PAST FEW DAYS FOR DAWN ON SUNDAY. THE STRONG LOW LEVEL WARM AIR ADVECTION WILL BE WORKING HARD NOW...INTO TONIGHT...TO MOISTEN THE DRY LOW LEVELS. 850 FLOW OF 40 KNOTS PERPENDICULAR TO THE ISOTHERMS. 850 TEMP GRADIENT ABOUT 10 DEGS BETWEEN NASHVILLE AND CRW AT 03Z TONIGHT. NO MAJOR CHANGES MADE IN THE LATE MORNING UPDATE. LIKE OUR TRANSITION TO MIXTURE 12 TO 15Z MONDAY IN THE DOWNSLOPE AREAS...AND LIKE HOLDING ONTO THE SLEET AND FREEZING RAIN IN THE SOUTHEAST UPSLOPE AREAS THROUGH MUCH OF MONDAY...AND EVEN INTO MONDAY NIGHT FOR POCAHONTAS COUNTY. WILL REVISIT OUR HEADLINES THIS AFTERNOON TO SEE IN ANY MINOR CHANGES ARE WARRANTED. && .SHORT TERM /MONDAY NIGHT THROUGH WEDNESDAY/... PERIOD STARTS WITH AN ONGOING WARM ADVECTION EVENT MON MORNING THAT CONTINUES MUCH OF THE DAY. DEEP LAYER SW FLOW OVERRUNS LOW LEVEL SE FLOW AT THE SFC...IN THE WAKE OF AN UPPER LEVEL S/W TROUGH LIFTING AWAY FROM THE AREA THROUGH THE ERN GREAT LAKES AND THE UPPER OHIO VALLEY. THE WARMING BRINGS THE COLUMN ABOVE FREEZING BELOW H85...BUT WITH A SFC-BASED COLD LAYER HANGING ON MUCH OF THE DAY ACROSS THE LOWLANDS...AND THROUGH MON NT IN THE MOUNTAINS. MODELS HAVE SLOWED BACK DOWN WITH A SECOND S/W TROUGH THAT APPROACHES THE AREA MON NT AND THEN CROSSES TUE MORNING. THIS GENERATES A RELATIVELY WEAK SFC LOW OVER THE TN VALLEY MON THAT THEN TRACKS NE ACROSS THE LOWLANDS OF THE FCST AREA MON NT. THIS TAKES OUT THE SFC BASED COLD LAYER ACROSS MUCH OF THE LOWLANDS BUT THE COLD AIR DAMMING WEDGE E OF THE APPALACHIANS PERSISTS. THE TRACK OF THE SYSTEM RIGHT OVER THE AREA LEAVES THE COLUMN BELOW H85 VERY CLOSE TO FREEZING THROUGHOUT MUCH OF THE AREA MUCH OF MON...AND ACROSS NW PORTIONS OF THE AREA...AND IN THE MOUNTAINS...MON NT AND TUE. THIS GIVES RISE TO MUCH UNCERTAINTY IN THE FCST PRECIPITATION TYPES AND AMOUNTS. THE WARM ADVECTION EVENT ONGOING FROM THE NEAR TERM INTO MON FEATURES A QPF AXIS ACROSS SRN PORTIONS OF THE AREA...MOST OF IT OCCURRING WHILE THE COLUMN IS STILL COLD ENOUGH TO SUPPORT SNOW. MOST OF THE ICE IN THIS EVENT COMES MON NT AS WARM AIR ALOFT OVERRIDES THE COLD AIR IN THE DAMMING WEDGE E OF THE APPALACHIANS. HAVE UP TO A QUARTER INCH OF ICE IN THE GREENBRIER VALLEY...BUT THERE IS THE POTENTIAL FOR MORE AS THE NAM SUGGESTS. AS A RESULT...WARNINGS FOR SNOW ARE POSTED INTO MON FOR THE SRN COAL FIELDS AND THE SRN MOUNTAINS...AND FOR SNOW AND ICE IN THE GREENBRIER VALLEY INTO TUE MORNING. ADVISORIES MOSTLY FOR SNOW ARE POSTED INTO MON FOR THE CENTRAL LOWLANDS AND FOR SNOW...AND A BIT OF ICE ON THE ERN EDGES...FOR THE CENTRAL AND NRN MOUNTAINS OF WV THROUGH MON NT. AFTER A DRIER BUT OVERCAST INTERLUDE BETWEEN SYSTEMS TUE...06Z MODEL RUNS ARE FARTHER S WITH ANOTHER UPPER LEVEL S/W TROUGH AND ASSOCIATED LOW PRESSURE SYSTEM PROGGED TO CROSS TUE NT. THIS WOULD BRING COLDER AIR BACK INTO THE AREA FROM THE W THROUGHOUT THE COLUMN OVERNIGHT TUE NT...CHANGING ANY RAIN...FREEZING RAIN OR MIXED PRECIPITATION THAT RETURNS TUE EVENING...BACK TO SNOW...WITH LIGHT ADDITIONAL AMOUNTS POSSIBLE. USED MOSTLY A NAM/GFS BLEND FOR TEMPERATURES SFC AND ALOFT...ALSO INCLUDED THE ECMWF AND WPC FOR QPF. && .LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/...
-- Changed Discussion --
OVERALL...QUIET AND WARMER WEATHER WILL TAKE HOLD IN THE LONG TERM. STILL SOME LIGHT UPSLOPE SNOW SHOWERS LINGERING BEHIND DEPARTING CLIPPER EARLY THURSDAY...BUT DRIER...AND WARMER AIR WILL GRADUALLY TAKE HOLD AS HIGH PRESSURE SURFACE AND ALOFT BUILD INTO THE REGION. TEMPERATURES TOWARDS THE END OF THE WEEK COULD EVEN CLIMB INTO THE 50S TO LOWER 60S ACROSS THE LOWLANDS...AS WAA INCREASES OUT AHEAD OF AN APPROACHING LOW...WHICH WILL SWEEP A COLD FRONT INTO THE REGION OVER THE WEEKEND...WITH LIGHT RAIN SHOWERS...AND COOLER TEMPERATURES TO END THE WEEK.
-- End Changed Discussion --
&& .AVIATION /19Z SUNDAY THROUGH FRIDAY/...
-- Changed Discussion --
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
-- End Changed Discussion --
&& .EQUIPMENT... HAVING ON/OFF PROBLEMS WITH THE CKB ASOS. TEMPERATURE READING TOO WARM AT TIMES. TROUBLE TICKET STILL EXISTS. && .RLX WATCHES/WARNINGS/ADVISORIES...
-- Changed Discussion --
WV...WINTER WEATHER ADVISORY UNTIL 7 AM EST TUESDAY FOR WVZ036>038- 047. WINTER STORM WARNING UNTIL 1 PM EST MONDAY FOR WVZ024-025- 033>035. WINTER WEATHER ADVISORY UNTIL 1 PM EST MONDAY FOR WVZ005>008- 013>016-026-027. WINTER STORM WARNING UNTIL 10 AM EST TUESDAY FOR WVZ046. OH...WINTER WEATHER ADVISORY UNTIL 1 PM EST MONDAY FOR OHZ083>087. KY...WINTER WEATHER ADVISORY UNTIL 1 PM EST MONDAY FOR KYZ101>103- 105. VA...WINTER STORM WARNING UNTIL 1 PM EST MONDAY FOR VAZ003-004.
-- End Changed Discussion --
&& $$ SYNOPSIS...KTB/MPK/SL NEAR TERM...KTB SHORT TERM...TRM LONG TERM...SL AVIATION...KTB EQUIPMENT...

USA.gov is the U.S. government's official web portal to all federal, state and local government web resources and services.