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
-- Highlight Changed Discussion --
-- Discussion containing changed information from previous version are highlighted. --
000 FXUS61 KRLX 081836 AFDRLX AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE CHARLESTON WV 236 PM EDT TUE JUL 8 2014 .SYNOPSIS... WEAK COLD FRONT PASSING NOW. ANOTHER WEAK COLD FRONT WEDNESDAY. HIGH PRESSURE BRINGS DRIER AIR TO THE REGION FOR THE END OF THE WEEK. ANOTHER SYSTEM OVER THE WEEKEND. && .NEAR TERM /THROUGH TONIGHT/... CONVECTION HAS FIRED ALONG A WEAK COLD FRONT THAT IS NOW PASSING THROUGH THE OHIO VALLEY. UNDER A SLIGHT RISK FROM SPC...WINDS ARE PRIMARILY THE MAIN THREAT WITH THE STORMS...ALTHOUGH BETTER DYNAMICS ARE CLEARLY NORTH OF OUR CWA IN PITTSBURGH AND STATE COLLEGE. 0-6KM BULK SHEAR OVER THE NORTHERN ZONES NOT QUITE IN THE 40KT RANGE...AND HAS AN ORIENTATION THAT IS MORE PARALLEL TO THE CURRENT LINE. THIS HINDERS THE WIND POTENTIAL SOMEWHAT. BEHIND THE FRONT...SOME BRIEF STABILIZATION IS POSSIBLE...WHICH COULD ERODE FROM THE MID LEVELS AGAIN INTO THE EVENING WHICH WOULD ALLOW FOR A SECOND ROUND OF MORE ISOLATED CONVECTION THAN ANYTHING. HAVE KEPT THE POPS LINGERING THROUGH THE CWA DURING THE DAYTIME HEATING HOURS...EVEN BEHIND THE FRONT. DRY THE WESTERN ZONES OUT OVERNIGHT. DEWPOINTS STAY UP OVERNIGHT WITH MUGGY CONDITIONS LINGERING...ESPECIALLY WHERE RAIN FALLS TODAY...WHICH WILL BE AT MOST AREAS...ESPECIALLY THE NORTHERN HALF OF THE CWA. EXPECTING DIURNAL CUMULUS WEDNESDAY THAT MAY LOOK ROBUST AT TIMES...BUT VERY LIMITED IN THE MOISTURE AVAILABLE ABOVE THE LOW LEVELS OF THE ATMOSPHERE. ISOLATED SHOWERS...OR A BRIEF STORM OR TOW...CANNOT BE RULED OUT WEDNESDAY...ESPECIALLY LATER IN THE DAY/EVENING. && .SHORT TERM /WEDNESDAY THROUGH FRIDAY/... NAM/GFS/ECMWF/CMC MODELS IN AGREEMENT IN THEIR QPF FIELDS PUSHING LAST RAIN SHOWERS OR THUNDERSTORMS TO THE EASTERN MOUNTAINS... MAINLY ACROSS THE SOUTH EARLY WEDNESDAY MORNING. THIS PCPN ACTIVITY IS ASSOCIATED WITH A SECOND COLD FRONT ENHANCED BY A H5 VORTICITY MAXIMA SINKING SOUTHEAST ACROSS THE AREA. BUFKIT SOUNDINGS INDICATE VERY DRY AIR ALOFT BEHIND THIS FRONT. YET ANOTHER H5 VORTICITY MAXIMA MOVES FROM THE NORTHWEST REACHING OUR EXTREME SOUTHEAST COUNTIES WEDNESDAY AFTERNOON. THEREFORE...DECIDED TO KEEP CHANCE POPS UNTIL THEN BEFORE ENDING ALL BY 00Z THURSDAY. TEMPERATURES WILL DEPEND ON THE DURATION OF CLOUD COVER ESPECIALLY WEDNESDAY AND THURSDAY. GENERALLY STAYED IN THE MID 80S LOWLANDS FOR WEDNESDAY...AND FEW DEGREES COOLER THURSDAY AS FLOW TURNS NORTHWEST TO NORTH BY THE AFTERNOON AND EVENING HOURS. && .LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/... USED A BLEND OF THE GFS AND ECMWF FOR FRIDAY. THIS LEAVES THE AREA UNDER A HIGH PRESSURE SYSTEM...BUT A BIT OF MOISTURE REMAINS IN THE NORTHERN MOUNTAINS....SO CAN NOT RULE OUT A THUNDERSTORM. FOR SATURDAY THROUGH MONDAY...SWITCHED TO A BLEND OF THE GFS/GEFS ENSEMBLE MEAN AND ECMWF ENSEMBLE MEAN. THIS BRINGS A SYSTEM INTO THE CENTRAL APPALACHIANS OVER THE WEEKEND...LINGERING INTO MONDAY. && .AVIATION /19Z TUESDAY THROUGH SUNDAY/... LINE OF CONVECTION HAS DEVELOPED QUICKLY AND WILL BE CROSSING THE OHIO RIVER SOON. CKB...EKN...AND PKB ARE IN A SEVERE THUNDERSTORM WATCH...PRIMARILY FOR WIND...BUT AS OF RIGHT NOW WITH THE APPROACHING LINE...WINDS ALOFT ARE PARALLEL TO THE LINE AS IT MOVES TO THE EAST. THIS WILL HAMPER THE WIND GUSTS SOMEWHAT...SO WILL KEEP TAF GUSTS BELOW 40KTS. TIMING THE LINE IS USUALLY TRICKY...AND THIS IS NO EXCEPTION. TEMPOS WERE A NECESSITY TODAY BECAUSE OF THIS...BUT WORKED TO KEEP THEM UNDER 2 HOURS. MAY GET SOME REDEVELOPMENT LATER THIS AFTERNOON/EVENING...BUT THE THREAT FOR ISOLATED SHOWERS AND STORMS WILL RETURN. WINDS WILL GUST OUT OF THE SOUTHWEST TO 25KTS. THERE WILL BE A FRONTAL PASSAGE IN THE NEXT TWO HOURS...BUT THE WIND SHIFT WILL BE MINIMAL TO NONE...AND IT SHOULD NOT AFFECT VELOCITIES AS MUCH AS THE LINE OF STORMS. GETTING INTO TONIGHT BECOMES CHALLENGING AS WELL. LOCALES RECEIVING RAIN...AS TYPICAL...WILL HAVE A BETTER SHOT AT FOG...ALTHOUGH IT APPEARS THE WIND MAY TRY TO STAY ABOVE CALM. THIS WILL MAKE FOG/MIST DEVELOPMENT QUESTIONABLE...BUT THE SYNOPTIC WIND MAY BE TRUMPED BY MESO HIGH AIR FROM CONVECTION EARLIER IN THE PERIOD. FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 18Z WEDNESDAY... FORECAST CONFIDENCE: LOW TO MEDIUM. ALTERNATE SCENARIOS: CONFIDENCE IS HIGH WITH THE CONVECTIVE OCCURRENCES...JUST NOT THE TIMING AS MUCH. FOG/MIST TONIGHT IS ALSO IN QUESTION. 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 18 19 20 21 22 23 00 01 02 03 04 05 EDT 1HRLY 14 15 16 17 18 19 20 21 22 23 00 01 CRW CONSISTENCY H H H H H H H H H H H M HTS CONSISTENCY H H H H H H H H H H H M 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 M 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 18Z WEDNESDAY... LOCAL IFR IN SHOWERS AND THUNDERSTORMS THROUGH EARLY WEDNESDAY... WITH LINGERING IFR CIGS POSSIBLE THROUGH LATE WEDNESDAY MORNING PARTICULARLY ACROSS HIGHER TERRAIN. && .RLX WATCHES/WARNINGS/ADVISORIES... WV...NONE. OH...NONE. KY...NONE. VA...NONE. && $$ SYNOPSIS...ARJ/26 NEAR TERM...26 SHORT TERM...ARJ LONG TERM...RPY AVIATION...26

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