Area Forecast Discussion
Issued by NWS Charleston, WV

Current Version | Previous Version | Text Only | 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
-- Highlight Changed Discussion --
-- Discussion containing changed information from previous version are highlighted. --
000 FXUS61 KRLX 301412 AFDRLX AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE CHARLESTON WV 1012 AM EDT THU OCT 30 2014 .SYNOPSIS... HIGH PRESSURE TODAY. LOW PRESSURE WITH RAIN FRIDAY EVENING. COLDER AIR AND THE LOW SHOULD RESULT IN ACCUMULATING SNOW IN THE MOUNTAIN COUNTIES OVERNIGHT FRIDAY NIGHT INTO SATURDAY. && .NEAR TERM /THROUGH TONIGHT/...
-- Changed Discussion --
15Z UPDATE... NO MAJOR CHANGES. PREVIOUS DISCUSSION... HIGH PRESSURE...CURRENTLY CENTERED OVER THE MIDDLE MISSISSIPPI VALLEY...WILL BUILD NORTHEAST INTO THE AREA BY LATE TODAY...AND THEN TO OUR EAST BY LATE TONIGHT. EXPECT AN AREA OF LOW PRESSURE WILL BE LOCATED OVER THE GREAT LAKES REGION BY LATE TONIGHT...WITH A COLD FRONT EXTENDING SOUTHWEST ACROSS CENTRAL KY INTO SOUTH TEXAS. AS EXPECTED...CLOUDS WERE DEVELOPING...MAINLY ACROSS NORTHERN PORTIONS OF THE AREA. SOME CLOUDS SHOULD CONTINUE TODAY...WITH SOUTHERN PORTIONS OF THE REGION SEEING MORE SUNSHINE THAN THE NORTH. AS THE LOW AND ASSOCIATED COLD FRONT APPROACH FROM THE WEST... EXPECT CLOUDS WILL BEGIN TO THICKEN AND LOWER...WITH MOSTLY CLOUDY SKIES EXPECTED BY LATE TONIGHT. POPS SHOULD BEGIN TO INCREASE FROM THE WEST LATE AS WELL. FORECASTED HIGHS TODAY LOOKED GOOD AND HAVE ONLY MADE SOME TWEAKS TO REFLECT LATEST TRENDS IN GUIDANCE. FOR TONIGHT...LATEST GUIDANCE IS COOLER THAN THE PREVIOUSLY FORECASTED VALUES. WITH LIGHT WINDS AND DRY AIR...THIS TREND IS BELIEVABLE. HOWEVER...FEEL INCREASING CLOUDS SHOULD ACT TO LIMIT OF RADIATIONAL COOLING THAT MAY OCCUR. HAVE LOWERED OVERNIGHT LOWS...HOWEVER...NOT AS MUCH AS SUGGESTED BY THE LATEST GUIDANCE.
-- End Changed Discussion --
&& .SHORT TERM /FRIDAY THROUGH SUNDAY NIGHT/...
-- Changed Discussion --
FIRST MEANINGFUL SNOW OF THE SEASON ANTICIPATED FOR THE WV AND VA MOUNTAINOUS COUNTIES...AND PERHAPS HILLTOPS IN THE SOUTHERN WV COAL FIELDS...OVERNIGHT FRIDAY NIGHT AND SATURDAY MORNING... WHATEVER THE WINTER OF 2014/15 WILL BRING...IT BEGINS EARLY AND LOUDLY...AS MAJOR E COAST L/W TROUGH AMPLIFICATION TAKES PLACE EARLY THIS PERIOD. A NRN UPPER LEVEL LOW DROPS ALMOST DUE S...DOWN THE BACKSIDE OF THE AMPLIFYING L/W AND INTO THE BASE...OR FROM THE GREAT LAKES TO THE SMOKIES...12Z FRI-12Z SAT. A LEAD SRN STREAM S/W TROUGH ALREADY IN THE BASE OF THE L/W OVER THE SERN STATES AS OF 12Z FRI...MOVES UP THE E SIDE OF THE L/W...ALONG THE E COAST...GENERATING AN INITIAL SFC WAVE ALONG AN OFFSHORE BAROCLINIC ZONE. FRI FINDS THE FCST AREA ALREADY IN IN RELATIVELY DRY...CHILLY AIR NEARLY CAPABLE OF SUPPORTING SNOW WITH KEY VALUES NEAR THRESHOLDS...LIKE 0C AT H8.5 AND 540 KM BETWEEN H5 AND H10...ALONG WITH PROGGED PW VALUES OF ONLY TWO THIRDS OF AN INCH. AS SUCH...THE NRN STREAM UPPER LEVEL LOW WILL NOT HAVE MUCH MOISTURE OR BAROCLINICITY TO WORK WITH AS IT DIGS THROUGH OR JUST W OF THE FCST AREA...WITH ASSOCIATED FRONTOGENETIC FORCING NOT REALLY CRANKING UP UNTIL THE LOW APPROACHES THE SE COAST. SHOWERS WILL BREAK OUT FRI AS THE SFC COLD FRONT ASSOCIATED WITH THE NRN STREAM FEATURE...APPROACHES AND THEN MOVES THROUGH FROM THE W. PRECIPITATION WILL LIKELY BECOME MORE WIDESPREAD FRI NT INTO SAT...AS THE NEGATIVE TILT FEATURE DIGGING S OF THE AREA PLACES THE AREA IN STRONG FORCING INCLUDING Q VECTOR CONVERGENCE. THE AFOREMENTIONED FACTORS WILL KEEP QPF VALUES MAINLY BELOW A HALF AN INCH / 6 HRS. THE COLD CORE SLIDES SEWD ACROSS SW PORTIONS OF THE FCST AREA FRI NT INTO SAT...WHILE THE WARMER AIR GETS HUNG UP OVER NERN PORTIONS OF THE FCST AREA FRI INTO FRI NT...UNTIL THE PRIMARY SFC LOW JUST TO THE N FILLS BY SAT MORNING. THE WARM BOUNDARY LAYER AIR DOES NOT GET COMPLETELY ERADICATED...KEEPING ACCUMULATING SNOW LEVELS ABOVE 2500 OR EVEN 3000 FT...WITH LEVELS PERHAPS GETTING BELOW 2500 FT OVER SW PORTIONS OF THE FCST AREA...CLOSER TO THE UPPER LOW TRACK. ALL OF THIS SORT OF BALANCES SNOW AMTS IN THE MOUNTAINS THE COLDEST AIR OVER THE SMALLER SRN MOUNTAINS. GENERALLY LOOKING AT COUNTY AVERAGES IN THE ADVISORY RANGE AT BEST...WITH PEAK AMOUNTS NEAR 4 INCHES FOR THE SRN MOUNTAINS AND AS HIGH AS 6 INCHES AT SNOWSHOE. WILL THUS MAINTAIN HWO MENTION FOR THE MOUNTAINOUS COUNTIES. AS THE L/W SHIFTS E...THE SYSTEM SCOOTS UP THE E COAST...OFFSHORE...IT MAKE TAKE UNTIL SUN MORNING FOR THE UPSLOPE SNOWS SHOWERS TO WANE AND THE CLOUDS TO BREAK UP. HIGH PRESSURE SAILS ACROSS SUN NT...PROVING IDEAL RADIATIVE COOLING MOST OF THE NT, HAVE TEMPERATURES NEARER LOWER SIDE OF GUIDANCE WITH BIAS CORRECTED GUIDANCE NOT A GOOD FIT IN THIS HIGHLY ANOMALOUS PATTERN.
-- End Changed Discussion --
&& .LONG TERM /MONDAY THROUGH WEDNESDAY/... MODELS RAPIDLY LIFT THE UPPER LOW OFF THE ATLANTIC COAST SATURDAY NIGHT...WHICH WILL END THE LINGERING MOUNTAIN SNOW SHOWERS...WITH ONLY ADDITIONAL MINOR HIGH ELEVATION ACCUMULATIONS BEFORE DAWN SUNDAY. STRONG DRY CANADIAN HIGH PRESSURE WILL THEN BE THE DOMINANT FEATURE THROUGH MONDAY. THE HIGH PRESSURE CENTER WILL SETTLE OVER THE AREA SUNDAY NIGHT...THEN SHIFT OFF THE ATLANTIC COAST EARLY NEXT WEEK. THIS WILL BRING A DRAMATIC TURNAROUND IN TEMPERATURES THIS PERIOD. WELL BELOW NORMAL TEMPERATURES THIS WEEKEND WITH WIDESPREAD SUB FREEZING TEMPERATURES SUNDAY NIGHT UNDER THE CENTER OF HIGH PRESSURE...WILL WARM UP TO NEAR NORMAL VALUES BY TUESDAY AS THE HIGH SHIFTS OFF THE ATLANTIC COAST. WHILE ALL THIS ABOVE IS HAPPENING...MODELS SHOW ANOTHER UPPER TROUGH DIGGING INTO THE MISSISSIPPI VALLEY AND DRIVING IT EAST TO AFFECT OUR AREA LATER TUESDAY AND WEDNESDAY. BY THIS TIME...TEMPERATURES WILL BE WELL ABOVE FREEZING FOR A RAIN EVENT. && .AVIATION /14Z THURSDAY THROUGH MONDAY/...
-- Changed Discussion --
15Z UPDATE... NO MAJOR CHANGES. VFR CONDITIONS FOR MOST SITES EXPECTED TO CONTINUE THROUGH THE AFTERNOON. PREVIOUS DISCUSSION... LATEST SURFACE OBSERVATIONS AND FOG CHANNEL SATELLITE IMAGERY SHOWS CLOUDS AT OR ABOVE 3500 FT WHERE DEVELOPING ACROSS PORTIONS OF THE AREA. STILL NOT REAL CONFIDENT THAT MUCH IN THE WAY OF MIST/FOG WILL DEVELOP BETWEEN 07Z AND 12Z...ESPECIALLY WITH THE DEVELOPMENT OF THESE CLOUDS. HAVE CONTINUED MENTION OF MVFR CONDITIONS WHERE THE CLOUDS ARE MOST LIKELY TO IMPACT...SUCH AS CRW AND EKN...WITH IFR CONDITIONS POSSIBLE ACROSS THE VALLEYS OF THE SOUTHERN COAL FIELDS. EXPECT ANY IFR/MVFR CONDITIONS THAT MAY DEVELOP WILL IMPROVE BY 14Z...WITH VFR CONDITIONS EXPECTED THROUGH THE REMAINDER OF THE AREA. WINDS SHOULD BE LIGHT THROUGH THE PERIOD. FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 12Z FRIDAY... FORECAST CONFIDENCE: MEDIUM. ALTERNATE SCENARIOS: TIMING AND DENSITY OF MORNING FOG. EXPERIMENTAL TABLE OF FLIGHT CATEGORY OBJECTIVELY SHOWS CONSISTENCY OF WFO FORECAST TO AVAILABLE MODEL INFORMATION: H = HIGH: TAF CONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL. M = MEDIUM: TAF HAS VARYING LEVEL OF CONSISTENCY WITH MODELS. L = LOW: TAF INCONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL. UTC 1HRLY 14 15 16 17 18 19 20 21 22 23 00 01 EDT 1HRLY 10 11 12 13 14 15 16 17 18 19 20 21 CRW CONSISTENCY H H H H H H H H H H H H HTS CONSISTENCY H H H H H H H H H H H H BKW CONSISTENCY H H H H H H H H H H H H EKN CONSISTENCY H H H H H H H H H H H H PKB CONSISTENCY H H H H H H H H H H H H CKB CONSISTENCY H H H H H H H H H H H H AFTER 12Z FRIDAY... IFR DEVELOPING FRIDAY EVENING IN RAIN...CHANGING TO MOSTLY SNOW OVER SOUTHERN MOUNTAIN COUNTIES INCLUDING BKW 06Z TO 12Z SATURDAY...WITH A RAIN AND SNOW MIXTURE IN THE LOWLANDS SATURDAY.
-- End Changed Discussion --
&& .RLX WATCHES/WARNINGS/ADVISORIES... WV...NONE. OH...NONE. KY...NONE. VA...NONE. && $$ SYNOPSIS...JSH/TRM NEAR TERM...JSH/LS SHORT TERM...TRM LONG TERM...JMV AVIATION...JSH/LS

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