Area Forecast Discussion
Issued by NWS Raleigh/Durham, NC

Current Version | Previous Version | Graphics & Text | Print | Product List | Glossary On
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. --
603 FXUS62 KRAH 141758 AFDRAH AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE RALEIGH NC 1255 PM EST SUN FEB 14 2016 .SYNOPSIS...ARCTIC HIGH PRESSURE WILL EXTEND ACROSS THE AREA TODAY. A DEVELOPING STORM SYSTEM WILL APPROACH FROM THE WEST TONIGHT AND MOVE EASTWARD ACROSS THE REGION MONDAY THROUGH TUESDAY. HIGH PRESSURE WILL GRADUALLY BUILD IN FROM THE NORTHWEST TUESDAY NIGHT AND WEDNESDAY. && .NEAR TERM /THROUGH SUNDAY/... AS OF 955 AM SUNDAY... VERY FEW CHANGES ARE NEEDED WITH THE FORECAST THIS MORNING... MAINLY A TWEAKING OF TODAY`S HIGHS AND A SLIGHT SLOWING OF THE ARRIVAL OF CLOUD COVER BASED ON MORNING TRENDS. HIGH RESOLUTION GUIDANCE STILL SUPPORTS HIGHS TODAY FROM 29-36... COLDEST IN THE NORTHEAST BENEATH THE CORE OF THE ARCTIC SURFACE RIDGE CENTERED OVER FAR ERN VA... DESPITE PLENTY OF SUNSHINE FOR AT LEAST THE FIRST HALF OF THE DAY. MID CLOUDS ARE PROJECTED TO SPREAD IN FROM THE WEST FROM LATE MORNING THROUGH THE AFTERNOON... WITH MOST PLACES MOSTLY CLOUDY BY LATE AFTERNOON. THE FORECAST FOR THE UPCOMING STORM STILL LOOKS ON TRACK... AND WHILE WE MAY SEE SOME RETURNS ON RADAR AS SOON AS LATE AFTERNOON / EARLY EVENING... THESE HYDROMETEORS WILL INITIALLY BE FIGHTING DRY AIR NEAR THE SURFACE AND THUS THE FORECASTED ONSET OF MEASURABLE PRECIP STILL LOOKS GOOD. WE WILL BE CONSIDERING WINTER WEATHER ADVISORIES THIS AFTERNOON... AND PERHAPS A WINTER STORM WARNING IN THE FAR NW... AFTER A THOROUGH ASSESSMENT OF MORNING MODEL RUNS. -GIH HERE IS THE PREVIOUS DISCUSSION FROM 4 AM... TODAY: MODIFIED SURFACE HIGH PRESSURE OVER THE AREA THIS WILL BEGIN TO SLOWLY SLIDE EASTWARD TOWARDS THE MID-ATLANTIC COAST THIS EVENING... WITH MID AND HIGH LEVEL CLOUD COVERING INCREASING AHEAD OF THE NEXT SYSTEM. AFTERNOON LOW LEVEL THICKNESS VALUES ARE EXPECTED TO BE WELL BELOW NORMAL... GENERALLY IN THE 1250S AND 1260S. THIS COMBINED WITH THE INCREASING CLOUD COVER WILL LEAD TO ANOTHER COLD DAY ACROSS THE AREA... WITH HIGHS EXPECTED TO BE GENERALLY RANGE FROM AROUND 30 N/NE TO NEAR 35 S/SW. TONIGHT THROUGH MONDAY NIGHT: SURFACE HIGH PRESSURE WILL SHIFT OFFSHORE TONIGHT... WHILE LOW LEVEL MOIST ADVECTION WILL COMMENCE OVER TOP THE LINGERING COLD DOME LEADING TO THE DEVELOP OF SOME LIGHT WINTRY PRECIPITATION. PRECIP IS EXPECTED TO FIRST DEVELOP ACROSS THE NORTHERN/NORTHWESTERN PIEDMONT INITIAL VERY LATE THIS EVENING/AFTER MIDNIGHT TONIGHT (GENERALLY IN THE FORM OF LIGHT SNOW TO START)... THEN FILLING IN FURTHER SOUTH AND EAST DURING THE EARLY MORNING HOURS OF MONDAY. THIS WILL RESULT IN THE DEVELOPMENT OF AN INSITU CAD WEDGE. WHILE THE PRECIP WILL GENERALLY REMAIN LIGHT TONIGHT INTO MONDAY MORNING... THE COLD SURFACE AIRMASS DEPOSITED BY THE MODIFIED ARCTIC SURFACE HIGH WILL LEAD TO ALL PRECIP EARLY MONDAY MORNING FALLING IN THE FORM OF A WINTRY MIX... WITH MORE SNOW/SLEET ACROSS THE NORTHERN/NORTHWEST PIEDMONT.... TO MORE OF A SLEET FREEZING RAIN MIX ACROSS THE FAR SOUTH/SOUTHEASTERN COUNTIES. GIVEN THE SURFACE HIGH WILL BE TRANSITORY (CONTINUING TO MOVE FURTHER AWAY AND OFFSHORE) COUPLED WITH A SURGING WARM NOSE EXPECT WE WILL SEE PRECIP GO FROM A WINTRY MIX TO FREEZING RAIN... THEN ALL RAIN IN A SOUTHEAST TO NORTHWEST FASHION ON MONDAY. EXPECT LOCATIONS ACROSS OUR FAR SOUTHERN AND EASTERN COUNTIES WILL BE ALL RAIN/DRIZZLE BY AROUND NOON MONDAY... WITH THE TRIANGLE AREA TURNING TO ALL RAIN/DRIZZLE BY MID AFTERNOON OR SO...WHILE THE TRIAD MAY HOLD ONTO SOME LIGHT FREEZING RAIN OR DRIZZLE INTO THE EVENING... BEFORE BECOMING ALL RAIN BY LATE EVENING. MOST OF THE PRECIP BY MIDDAY MONDAY IS EXPECTED TO BE QUITE LIGHT... AS THE 850MB WARM FRONT LIFTS TO THE NORTH OF THE AREA. THIS SHOULD LEAVE CENTRAL NC WILL SPOTTY LIGHT PRECIP/DRIZZLE. WRT TO ACCUMULATIONS. LOCATIONS ACROSS THE NORTHWEST PIEDMONT/NORTHERN PIEDMONT WILL SEE THE HIGHEST SNOW AND SLEET TOTALS... POSSIBLY 2 TO 3 INCHES... WITH LOCATIONS FARTHER SOUTH AND EAST SEEING LESS FOR A NUMBER OF REASONS (A LITTLE LESS QPF/LESS TIME WITH HIGHER SNOW/SLEET TO LIQUID RATIOS DUE TO THE WARM NOES/AND POSSIBLE LOSS OF SATURATION ABOVE -10C ACROSS THE FAR SOUTH/SOUTHEAST). THUS... OUTSIDE OF THE NW/N PIEDMONT WE WILL GENERALLY SEE SNOW/SLEET TOTALS OF AROUND AN INCH OR LESS. WITH REGARD TO ICE ACCRUAL... THINK WE SHOULD SEE AT LEAST TRACE AMOUNTS ACROSS ALL OF CENTRAL NC... THUS... AT LEAST A WINTER WEATHER ADVISORY WILL LIKELY BE NEEDED IN LATER SHIFTS FOR THE ENTIRE AREA. ICE ACCRUAL IS EXPECTED TO GENERALLY BE A TENTH OF AN INCH OR LESS... WITH THE HIGHEST TOTALS ACROSS THE PIEDMONT. AFTER COORDINATION WITH SURROUNDING OFFICES WE WILL KEEP THE CURRENT WATCH AS IS FOR NOW. HOWEVER... AS MENTIONED ABOVE AT LEAST A WINTER WX ADVISORY WILL BE NEED FOR TONIGHT INTO MONDAY FOR THE ENTIRE AREA... WITH PERHAPS A WINTER STORM WARNING NEEDED FOR A THE FAR N/NW PIEDMONT. LOWS TONIGHT ARE EXPECTED BE IN THE LOWER TO MID 20S. HIGH TEMPS MONDAY WILL RANGE FROM THE LOWER 30S NW TO THE LOWER TO MID 40S SE. THE MAIN S/W ENERGY AND ACCOMPANYING SURFACE LOW ARE EXPECTED TO MOVE THROUGH THE AREA MONDAY NIGHT INTO TUESDAY... WITH HEAVY RAIN AND POSSIBLY A FEW STORMS. TEMPS WILL INCREASE AHEAD OF THE SURFACE LOW AS THE COASTAL FRONT ATTEMPTS TO MOVE INLAND. THIS WILL ALLOW FOR NEAR STEADY TO RISING TEMPS OVERNIGHT... WITH LOWS FOR THE OVERNIGHT PERIOD LIKELY OCCURRING AT THE START OF THE PERIOD. TEMPS AT AROUND 12Z ARE EXPECTED TO BE IN THE UPPER 30S NW TO THE 50S SE. && .SHORT TERM /TUESDAY AND TUESDAY NIGHT/... AS OF 335 AM SUNDAY... SFC COLD FRONT ATTENDANT WITH THE S/W CROSSING THE MID ATLANTIC WILL ADVANCE QUICKLY EASTWARD ACROSS CENTRAL NC TUESDAY MORNING. NUMEROUS SHOWERS AHEAD OF THIS FEATURE SHOULD QUICKLY DIMINISH WEST-TO-EAST THROUGH 17Z. WESTERLY FLOW IN THE WAKE OF THIS FEATURE WILL ALSO AID TO DISSIPATE CLOUD COVERAGE AND LEAD TO A FAIRLY MILD AFTERNOON. AFTERNOON TEMPS SHOULD VARY FROM THE LOWER 50S NW TO THE LOWER 60S SE. ANOTHER S/W WILL CROSS IMMEDIATELY NORTH OF CENTRAL NC TUESDAY NIGHT...DRAGGING A SECONDARY COLD FRONT ACROSS OUR REGION. THIS FEATURE WILL BASICALLY BE MOISTURE STARVED THOUGH DECENT MID LEVEL LAPSE RATES MAY LEAD TO A FEW SPRINKLES OR LIGHT RAIN SHOWERS NEAR THE VA BORDER. && .LONG TERM /WEDNESDAY THROUGH SATURDAY/... AS OF 335 AM SUNDAY... AMPLIFIED L/W TROUGH THAT HAS PERSISTED OVER OUR REGION FOR MUCH OF FEBRUARY WILL RELAX...LEADING TO S/W RIDGING ALOFT BY THE END OF THE WEEK. THIS WILL LEAD TO A DEEP ZONAL FLOW...INITIATING A RETURN TO NEAR NORMAL AND EVENTUALLY ABOVE NORMAL TEMPS. AFTERNOON TEMPS WILL GENERALLY BE IN THE 50S WED-FRI. THE APPROACH OF A SFC COLD FRONT FROM THE NW LATE FRIDAY INTO SATURDAY WILL BACK THE FLOW TO A MORE SW DIRECTION...PUMPING WARM AIR RESIDING OVER THE DEEP SOUTH INTO CENTRAL NC. AFTERNOON TEMPS SATURDAY SHOULD CLIMB INTO THE 60S AREAWIDE. OVERNIGHT TEMPS WILL GENERALLY BE WITHIN A FEW DEGREES OF ABOVE FREEZING UNTIL LATE INTO THE WEEK WHEN AN UPTICK IN CLOUD COVERAGE AND A SW FLOW YIELDS MIN TEMPS IN THE 40S. DRY WEATHER EXPECTED THROUGH THE PERIOD AS MOISTURE RETURN WILL BE CHARACTERIZED AS WEAK. && .AVIATION /18Z SUNDAY THROUGH THURSDAY/... AS OF 1255 PM SUNDAY... A PERIOD OF WINTRY WEATHER IS EXPECTED STARTING THIS EVENING AND LASTING THROUGH MID EVENING MON... MAINLY AFFECTING NORTHERN TAF SITES (INT/GSO/RDU/RWI)... ALTHOUGH ACCRUAL AMOUNTS SHOULD BE FAIRLY LIGHT AT RDU/RWI WITH ONLY TRACE AMOUNTS AT FAY. VFR CONDITIONS HOLD AT ALL TAF SITES CURRENTLY. CLOUDS WILL THICKEN THIS EVENING BUT REMAIN VFR THROUGH 03Z. AFTER THIS TIME... BETWEEN 03Z AND 08Z... CIGS WILL LOWER TO MVFR FROM SOUTHEAST TO NORTHWEST (DETERIORATING FIRST AT FAY THEN AT RDU/RWI AND FINALLY AT INT/GSO). DURING THIS PERIOD... AREAS OF PRECIPITATION WILL SPREAD IN MAINLY AT INT/GSO... WITH MUCH MORE LIGHT AND PATCHY PRECIP AT RDU/RWI/FAY. INITIAL PRECIP TYPE WILL BE MOSTLY SNOW OR SNOW/SLEET TONIGHT... CHANGING TO MOSTLY FREEZING RAIN FROM SE TO NW (FIRST CHANGING AT FAY THEN AT RWI-RDU-GSO-INT IN THAT ORDER) MON MORNING THROUGH EARLY AFTERNOON. LOOKING BEYOND 18Z MON... AREAS OF PRECIP SHOULD BE ALL RAIN AT RWI/FAY BY 18Z... AT RDU BY 21Z... AND AT GSO/INT BY 02Z (MID EVENING MON). CIGS MON AFTERNOON WILL DROP TO MAINLY IFR/LIFR WITH MVFR TO IFR VSBYS... HOLDING THROUGH MIDDAY TUE WITH A PERIOD OF WIDESPREAD HEAVY RAIN EXPECTED LATE MON NIGHT INTO TUE MORNING... MOVING WEST TO EAST. AN ISOLATED STORM OR TWO IS POSSIBLE EARLY TUE MORNING AT RWI/FAY. VFR CONDITIONS ARE EXPECTED TO RETURN TUE AFTERNOON WITH A PERIOD OF GUSTY WINDS FROM THE WEST. VFR CONDITIONS WILL THEN DOMINATE THROUGH FRIDAY AS HIGH PRESSURE BUILDS IN. -GIH && .CLIMATE... HERE ARE THE RECORD LOWS AND RECORD LOW MAXIMUM TEMPERATURES FOR FEB 14TH. REC YR REC YR LOW LOW MAX ---------------------------------------------- GSO: 02/14 6 1905 22 1914 RDU: 02/14 -2 1899 27 1916 FAY: 02/14 12 1968 33 1916 && .RAH WATCHES/WARNINGS/ADVISORIES... WINTER STORM WATCH FROM LATE TONIGHT THROUGH MONDAY EVENING FOR NCZ007-021>023-038-039. WINTER STORM WATCH FROM MONDAY MORNING THROUGH MONDAY AFTERNOON FOR NCZ008>010-024>026-040-041-073>076. && $$ SYNOPSIS...HARTFIELD NEAR TERM...HARTFIELD/BSD SHORT TERM...WSS LONG TERM...WSS AVIATION...HARTFIELD CLIMATE...RAH

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