176 FXUS61 KRLX 270552 AFDRLX AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE CHARLESTON WV 1252 AM EST WED NOV 27 2013 .SYNOPSIS... STRENGTHENING LOW PRESSURE SYSTEM LIFTS NORTHEAST CHANGING RAIN TO SNOW OVERNIGHT. BLUSTERY WINDS ON WEDNESDAY. HIGH PRESSURE BUILDING IN ON THANKSGIVING DAY AND LINGERING FRIDAY. && .NEAR TERM /THROUGH TODAY/... BASED ON THE LATEST MODEL RUNS...WILL LOWER SNOW ACCUMULATIONS SLIGHTLY IN THE WESTERN COUNTIES FOR LATE TONIGHT AND WEDNESDAY MORNING. && .SHORT TERM /TONIGHT THROUGH FRIDAY/... COLDEST 850MB TEMPS ARRIVING AT THE START OF THE SHORT TERM...AND WILL CONTINUE SQUEEZING OUT MOISTURE IN THE FORM OF SNOW...ESPECIALLY ACROSS NE CWA. MOISTURE QUICKLY DEPARTS THROUGH THE EARLY MORNING ON THURSDAY BUT LINGERED UPSLOPE SNOW A BIT LONGER IN THE MOUNTAINS...WAITING FOR THE 850MB TEMPERATURE TROUGH TO START BREAKING DOWN WHICH SHOULD BE AROUND 15Z THURSDAY. SURFACE HIGH PRESSURE THEN MOVES IN FROM THE SW AS A WEAK UPPER TROUGH PASSES NORTH. WITH THE HIGH PRESSURE IN PLACE...SHOULD STAY DRY...BUT WENT WITH A BIT MORE MID TO HIGH CLOUD COVER ACROSS THE NORTH THURSDAY NIGHT AND FRIDAY. THURSDAY WILL BE A COLD DAY WITH 850S IN THE -13C TO -15C RANGE. FRIDAY WILL BE A BIT WARMER BY AFTERNOON...BUT EARLY MORNING SHOPPERS SHOULD BE PREPARED FOR A COLD START. ONLY MADE MINOR TWEAKS TO PREVIOUS FORECAST TEMPS...WENT A TOUCH COOLER WEDNESDAY NIGHT...AND A TOUCH WARMER FRIDAY. && .LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/... A RATHER TRANQUIL ZONAL FLOW WITH SOME WEAK TROUGH APPROACHING LATE IN THE WEEKEND. WILL CONTINUE BRINGING BACK SOME CHANCE POPS FOR LIGHT RAIN SUNDAY NIGHT AND BECOMING MORE WIDESPREAD MONDAY BEFORE DIMINISHING POPS MONDAY NIGHT. NOT ANY STRONG FEATURES OR FRONTS EXPECTED DURING THIS PERIOD. NO BIG DEVIATIONS FROM HPC MEDIUM RANGE GROUP TEMPERATURES. && .AVIATION /05Z WEDNESDAY THROUGH SUNDAY/... IFR CONDITIONS DOMINATE THE FRONT END OF THE TAFS WITH THE RAIN FINALLY CHANGING OVER TO SNOW. THERE COULD BE SOME BOUNCING OF THE OBSERVATIONS IN AND OUT OF THE HEAVIER BATCHES OF SNOW PUSHING THROUGH. BKW TO LIKELY STAY LIFR OVER THE NEXT FEW HOURS. ALL LOCATIONS SHOULD BENEFIT FROM CEILING RISES AS THE WINDS BECOME GUSTY OUT OF THE NORTHWEST. WILL STILL HAVE TROUBLE GETTING OUT OF THE IFR CATEGORY...BUT SHOULD HAPPEN LATER TODAY. AFTER SUNRISE TODAY...MUCH OF THE SYNOPTIC SCALE SNOW WILL HAVE MOVED OUT AS WE LOSE THE BULK OF THE DEEPER MOISTURE. HOWEVER...CONVECTIVE SNOW SQUALLS ARE POSSIBLE THROUGH 20Z TODAY...WHICH SUPPORTS THE EXTENSION OF THE IFR VISIBILITIES. HOWEVER...THESE WILL OFF AND ON IN NATURE...AND WILL LIKELY NEED WIDE TEMPOS TO COVER FOR PERIODS WHEN THE SNOW STOPS. VFR CONDITIONS CREEP IN LATER THIS EVENING FOR HTS...EKN...PKB...AND BKW. FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 06Z THURSDAY... FORECAST CONFIDENCE: MEDIUM. ALTERNATE SCENARIOS: VISIBILITY RESTRICTIONS COULD VARY WITH SNOW. 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 WED 11/27/13 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 M M M H H H M M M M L L HTS CONSISTENCY H H H M M M M L H H H H BKW CONSISTENCY M M M M H H H L L L L L EKN CONSISTENCY M M M M M M M M M M M L PKB CONSISTENCY H H M M M M M M L L L L CKB CONSISTENCY M M M H H H M M M M M L AFTER 06Z THURSDAY... IFR CONDITIONS EXPECTED WEDNESDAY NIGHT IN SNOW DUE TO A LINGERING WINTER STORM SYSTEM...PARTICULARLY ACROSS THE MOUNTAINS. && .RLX WATCHES/WARNINGS/ADVISORIES... WV...WINTER WEATHER ADVISORY UNTIL 1 PM EST THIS AFTERNOON FOR WVZ005>007. WINTER STORM WARNING UNTIL 1 AM EST THURSDAY FOR WVZ035>037. WINTER WEATHER ADVISORY UNTIL 7 PM EST THIS EVENING FOR WVZ008>011-013>020-024>034-039-040. WINTER STORM WARNING UNTIL 4 AM EST THURSDAY FOR WVZ038-046- 047. OH...WINTER WEATHER ADVISORY UNTIL 1 PM EST THIS AFTERNOON FOR OHZ067-075-076-083>087. WINTER STORM WARNING UNTIL 10 AM EST THIS MORNING FOR OHZ066. KY...WINTER WEATHER ADVISORY UNTIL 1 PM EST THIS AFTERNOON FOR KYZ101>103-105. VA...WINTER WEATHER ADVISORY UNTIL 7 PM EST THIS EVENING FOR VAZ003- 004. && $$ SYNOPSIS...KTB/MZ/SL NEAR TERM...RPY SHORT TERM...MZ LONG TERM...KTB AVIATION...26