067 FXUS61 KRLX 060648 AFDRLX AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE CHARLESTON WV 148 AM EST MON FEB 6 2012 .SYNOPSIS... AN UPPER LEVEL DISTURBANCE PASSES LATE TODAY. A COLD FRONT WITH A WEAK WAVE CROSSES WEDNESDAY NIGHT. HIGH PRESSURE IN CONTROL THROUGH FRIDAY NIGHT. INCREASING CLOUDS SATURDAY. && .NEAR TERM /THROUGH TONIGHT/... EDGE OF LOW STRATUS JUST NOW EXITING DICKENSON CO IN SW VA AS OF 06Z. FG HAS FORMED IN THE RVR VALLEYS GENERALLY ALONG AND S OF I64 CORRIDOR AND MTN VALLEYS. FURTHER N AND W DRIER AIR IN THE FORM OF LWR SFC DWPTS HAS ADVECTED IN WITH ENOUGH OF A DWPT DEPRESSION TO SUPPRESS MUCH IN THE WAY OF FG THUS FAR. EXPECT THAT GENERAL TREND TO HOLD REMAINDER OF THE NIGHT WITH DENSE FG FORMING ACROSS RVR VALLEYS ACROSS COAL FIELDS...SW VA...AND SOUTHERN MTN VALLEYS. AFOREMENTIONED STRATUS MAY TRY TO SNEAK BACKN INTO SW VA COUNTIES BY DAWN AS LLVL FLOW TURNS MORE SOUTHERLY AHEAD OF APPROACHING UPR LOW. SPEAKING OF WHICH...THERE HAS BEEN A TREND TO SLOW THIS THING DOWN A BIT FROM LAST NIGHTS THINKING. PREV SHIFT HAS GENERALLY CAPTURED THIS IDEA AND ONLY TWEAKS NEEDED TO TIMING OF CLDS AND SCHC POPS ACROSS THE SOUTH FOR LATER TDY. COLUMN BECOMES SATURATED TO NEAR H8 ACROSS FAR SOUTH. THIS COMBINED WITH SOME LIFT PROVIDED FROM DIV FROM APPROACHING UPR LOW SHOULD ALLOW VERY LIGHT PCPN TO BREACK OUT. STILL LOOKS AS THOUGH MANY PLACES ACROSS THE SOUTH WILL BE HARD PRESSED TO MEASURE...HENCE THE LOW POPS. HAVE HELD POPS OUT TIL AFTER 18Z ACROSS SW VA...AFTER 21Z FOR SOUTHERN MTNS...00Z CENTRAL MTNS. BL TEMPS ENSURE A LIQUID EVENT. ASSOCIATED CLD SHIELD IN FORM OF 3 TO 5 THSND FT DECK EXPECTED TO MAKE IT TO PERHAPS JUST N OF I 64 CORRIDOR THIS AFTN AND OVER TO NORTHERN MTNS THIS EVE. SHOULD SEE SOMEWHAT OF A SHARP CLD LINE WITH NORTHERN LOWLANDS AND SE OH SEEING A MAINLY SUNNY SKY TDY. WILL ROLL WITH WARMER MAV ACROSS THE NORTH AND SE OH AND TWEAK DOWN THE NUMBERS ACROSS THE SOUTH WHERE CLDS SHOULD KEEP TEMPS IN CHECK. STILL MILD FOR FEB STANDARDS. SKY WILL CLEAR THIS EVE FROM W TO E WITH PASSAGE OF UPR LOW. HAVE CLDS CLEARING ALL LOCATIONS BY 09Z. TONIGHT WITH MTN CLDS FROM UPR LOW BECOMING EXODUS BY 09Z. SFC HIGH BUILDING IN OVERHEAD LATE MAY ALLOW FOR SOME PATCHY RVR VALLEY FG IN THE USUAL SUSPECTED AREAS. && .SHORT TERM /TUESDAY THROUGH WEDNESDAY/... NUDGED TIMING AND INTENSITY OF UPPER LOW CROSSING SOUTHERN PERIPHERY OF CWA MONDAY NIGHT SLIGHTLY TOWARD THE NAM12. FEATURE SHOULD BE JUST EXITING THE AREA AT THE START OF THE PERIOD...WITH ATTENDANT DYNAMICS AND MOISTURE TO PUSH EASTWARD. NAM12 IS THE SHARPEST OF THE NCEP MODELS IN TERMS OF HANDLING THIS SHORTWAVE AND MAY BE A BIT OVERDONE. HOWEVER...IT HAS BEEN FAIRLY CONSISTENT OVER TIME. ONCE UPPER LOW EXITS...SFC HIGH PRESSURE BUILDS WITH FURTHER DRYING OF THE ATMOSPHERIC COLUMN ON TUESDAY. BRING BACK AN INCREASE IN CLOUDS TUESDAY NIGHT INTO WEDNESDAY AS WEAK S/W TROUGH TRAVERSES. FOR TEMPS...TRENDED ALONG WITH INHERITED FORECAST WITH MINOR ADJUSTMENTS. TEMPS WILL STILL BE ON THE WARM SIDE FOR THIS TIME OF YEAR. && .LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/... FRONT TO PASS...ALONG WITH VORT MAX TRAVELING THROUGH THE REGION. MOISTURE LACKING WITH THIS AND ONLY WENT WITH SLGT CHC POPS. TEMPS SHOULD BE WARM ENOUGH FOR ANY PRECIP TO BE LIQUID IN THE LOWLANDS WITH A MIX IN ACROSS THE NORTHERN ZONES AND MAINLY SNOW IN THE HIGHER ELEVATIONS OF THE NORTHERN MOUNTAINS BEFORE ENDING. HIGH PRESSURE THEN TAKES CONTROL THROUGH FRIDAY NIGHT...WITH TEMPERATURES BEING A MIX OF HPC AND MODEL GUID. A SOUTHERN SYSTEM WORKS ITS WAY NORTHEASTWARD ON SATURDAY...WITH INCREASING CLOUDS. THIS SYSTEM WILL THEN SLIDE ACROSS THE CAROLINAS KEEPING ANY PRECIP OUT OF AND TO OUR SOUTH. && .AVIATION /06Z MONDAY THROUGH FRIDAY/... SHARP EDGE TO LOW STRATUS DECK HOVERING ACROSS SW VA AS OF 06Z. THIS WILL TRY TO RETURN N BY DAWN AS LLVL FLOW TURNS MORE SOUTHERLY AHEAD OF APPROACHING UPR LOW. ELSEWHERE...GENERALLY MVFR VSBY IN FG ACROSS RVR VALLEYS CENTRAL AND SOUTHERN WV...SW VA...AND MTN VALLEYS. LLVL DRIER AIR ADVECTING IN FROM S WILL KEEP NORTHERN TAF SITES GENERALLY FREE FROM ANY AVIATION VSBY RESTRICTIONS WITH EXCEPTION OF KEKN WHERE MVFR VSBY POSSIBLE. ANY FG WILL LIFT BY 13Z AS CLDS INCREASE ACROSS THE SOUTHERN LOCALES. UPR LOW APPROACHES LATE IN DAY WITH 4 TO 6 THSND FOOT CIGS ADVANCING N INTO CENTRAL LOWLANDS AND NORTHERN MTNS AFTER 18Z. SOME VERY LIGHT PCPN POSSIBLE ACROSS SOUTHERN WV AND SW VA AFTER 18Z. HOWEVER CONFIDENCE NOT HIGH ENOUGH TO INCLUDE IN KBKW TAF ATTM. FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 06Z TUESDAY... FORECAST CONFIDENCE: MEDIUM. ALTERNATE SCENARIOS: TIMING AND INTENSITY OF FOG CENTRAL AND SOUTHERN AERAS. 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. DATE MON 02/06/12 UTC 1HRLY 06 07 08 09 10 11 12 13 14 15 16 17 EST 1HRLY 01 02 03 04 05 06 07 08 09 10 11 12 CRW CONSISTENCY L L M M H H H H H H H H HTS CONSISTENCY L L H H L L L L L M H H BKW CONSISTENCY H H H H H H H H H H H H EKN CONSISTENCY L L L L L L L L M M H H PKB CONSISTENCY M M M M H H H H H H H H CKB CONSISTENCY M M M M M M M M H H H H AFTER 06Z TUESDAY... NO WIDESPREAD IFR OR WORSE CONDITIONS EXPECTED AT THIS TIME. && .RLX WATCHES/WARNINGS/ADVISORIES... WV...NONE. OH...NONE. KY...NONE. VA...NONE. && $$ SYNOPSIS...RPY/30 NEAR TERM...30 SHORT TERM...KMC LONG TERM...JS AVIATION...30