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. --
000 FXUS62 KRAH 271608 AFDRAH AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE RALEIGH NC 1105 AM EST THU NOV 27 2014 .SYNOPSIS...AN UPPER LEVEL DISTURBANCE AND ASSOCIATED LOW PRESSURE SYSTEM WILL TRACK EAST ACROSS THE REGION THROUGH EARLY THIS AFTERNOON. HIGH PRESSURE WILL BUILD INTO THE REGION FROM THE WEST LATE TODAY THROUGH TONIGHT... THEN SETTLE OVER THE CAROLINAS ON FRIDAY AND SATURDAY... BEFORE PUSHING EAST OFF THE COAST SUNDAY. && .NEAR TERM /THROUGH TONIGHT/... AS OF 1105 AM THURSDAY... HAPPY THANKSGIVING! FORECAST REQUIRED LITTLE CHANGE THIS MORNING. THE LEADING SHORTWAVE TROUGH EVIDENT ON WATER VAPOR IMAGERY IS NOW WOBBLING ACROSS NORTH CENTRAL NC... GENERATING NUMEROUS SHOWERS ACROSS THE NRN CWA. FAST ON ITS HEELS IS THE SECOND WEAKER WAVE GENERATING SNOW SHOWERS ON THE WEST SLOPES OF THE SOUTHERN APPALACHIANS... HOWEVER MUCH OF THIS APPEARS TO BE DRYING UP AS THE PRECIP HEADS JUST EAST OF THE MOUNTAINS WHERE THE LOW LEVEL FLOW HAS A NOTABLE DOWNSLOPE COMPONENT. NEVERTHELESS... BOTH ON THE TAIL END OF THE LEADING WAVE AND WITH THE SECOND WAVE AS IT SHIFTS EAST ACROSS THE STATE... WILL NEED TO MONITOR FOR A FEW POCKETS OF MIXED RAIN AND WET SNOW OVER THE EXTREME NNW CWA. IN FACT... KRAX DUAL POL PRODUCTS INDICATE THE MELTING LEVEL AT AROUND 2200 FT... A BIT LOWER THAN RAP FORECAST SOUNDINGS SUGGEST... SO WE COULD DEFINITELY SEE SOME WET FLAKES WHERE PRECIP RATES ARE HIGHER. TEMPS RANGE FROM THE UPPER 30S TO LOWER 40S NORTH TO THE UPPER 40S/NEAR 50 SOUTH... AND THE NORTHERN HALF IS UNLIKELY TO SEE MUCH MORE THAN A ONE TO PERHAPS TWO CATEGORY CLIMB FOR THE REST OF THE DAY... AND EVEN THEN ONLY IF WE CAN GET ENOUGH SUNSHINE. THESE CHANCES DON`T LOOK TOO GOOD GIVEN THE PERSISTENT MOISTURE IN THE LOW LEVELS NOTED ON UPPER AIR ANALYSES. WILL ADJUST NORTHERN HIGHS DOWN JUST A TAD... TO RANGE FROM MID 40S NORTH (AND AGAIN THIS MAY BE OPTIMISTIC) UNDER MOSTLY CLOUDY SKIES TO MID 50S SOUTH (WHICH COULD BE PESSIMISTIC GIVEN THE FAIR SKIES THERE). -GIH TONIGHT...SKIES WILL CLEAR OFF FAIRLY QUICKLY WEST-TO EAST LATE THIS AFTERNOON EARLY EVENING AS DRIER AIR OVERSPREADS THE REGION. COLD AIR ADVECTION WILL KEEP THE NEAR SURFACE ATMOSPHERE WELL MIXED UNTIL JUST PRIOR TO DAYBREAK. THE CAA WILL SEND TEMPS INTO THE MID-UPPER 20S BY EARLY FRIDAY. && .SHORT TERM /FRIDAY AND FRIDAY NIGHT/... AS OF 305 AM THURSDAY... FRIDAY...CHILLY HIGH PRESSURE WILL BUILD INTO AND SETTLES OVERHEAD. LOW LEVEL THICKNESSES AVERAGE 45M BELOW NORMAL...SUGGESTIVE OF MAX TEMPS 10-14 DEGREES BELOW NORMAL. THIS YIELDS MAX TEMPS IN THE LOW- MID 40S. SKIES WILL REMAIN MOSTLY CLEAR ASIDE FROM A FEW PASSING CIRRUS IN THE AFTERNOON. -WSS FRIDAY NIGHT: SURFACE HIGH PRESSURE WILL SETTLE OVER THE REGION ON FRIDAY NIGHT. MEANWHILE... MID LEVEL FLOW WILL REMAIN OUT OF THE WNW WITH THE POTENTIAL FOR A FEW WEAK DISTURBANCES TO MOVE ACROSS THE MID ATLANTIC REGION. HOWEVER... WE WILL REMAIN DRY WITH ONLY AN INCREASE IN SOME HIGH CLOUDS ON SATURDAY MORNING. STILL THINK THE CLOUDS WILL BE THIN ENOUGH NOT TO HAVE A SIGNIFICANT IMPACT ON LOW TEMPS. GIVEN THIS... THINK WE SHOULD SEE TEMPS PLUMMET INTO THE 20S ACROSS THE ENTIRE AREA... WITH LOWS IN THE MID TO UPPER 20S (MAYBE EVEN A FEW LOWER 20S IN THE USUAL RURAL COLD SPOTS DEPENDING ON THE CLOUD COVER). -BSD && .LONG TERM /SATURDAY THROUGH WEDNESDAY/... AS OF 310 AM THURSDAY... HIGH PRESSURE WILL SHIFT TO THE SOUTH AND EAST OF CENTRAL NC THIS WEEKEND ALLOWING FOR A WARMING TREND. HIGH TEMPS ARE EXPECTED TO BE IN THE LOWER TO MID 50S FOR SATURDAY AND LOWER TO MID 60S FOR SUNDAY. MID LEVEL RIDGING IS FORECAST TO BUILD NORTHWARD DURING THIS TIME FRAME AND NUDGE INTO OUR AREA. HOWEVER... AS A NORTHERN STEAM TROUGH IS FORECAST TO TRACK NEAR THE U.S./CANADIAN (EAST COAST THAT IS) BORDER DURING THIS TIME FRAME A TRAILING COLD FRONT WILL DROP SOUTHWARD AND INTO CENTRAL NC EARLY NEXT WEEK. MODEL GUIDANCE HAS TRENDED TOWARDS THE SURFACE FRONT MOVING INTO THE AREA ON MONDAY NIGHT INTO EARLY TUESDAY MORNING... PUSHED BY A 1035-1040 MB SURFACE HIGH TO THE NORTH/NORTHWEST. THIS SHOULD ALLOW FOR ONE LAST WARM DAY ON MONDAY... WITH HIGHS IN THE 60S TO LOWER 70S SOUTH. GIVEN THE LAST SEVERAL DAYS MEDIUM RANGE MODELS HAVE TRENDED WETTER WITH THE AFOREMENTIONED FRONT AND THE POTENTIAL FOR AT LEAST SOME HYBRID COLD AIR DAMMING FOR MONDAY NIGHT INTO TUESDAY. HOWEVER... WPC STILL PREFERS TO KEEP POPS LOW WITH THE ARRIVAL OF THE FRONT GIVEN THE APPARENT SPREAD IN GUIDANCE/ENSEMBLES GUIDANCE OVER THE PAST FEW DAYS AND DIFFERENCES WITH THE OPERATIONAL MODELS VS THEIR ENSEMBLES. THUS... FOR NOW PREFER TO KEEP POPS AT SLIGHT CHANCE FOR MONDAY NIGHT INTO TUESDAY AND TREND TEMPS DOWNWARD. FOR WEDNESDAY... WE MAY HAVE SOME FORM OF LINGERING CAD ACROSS THE AREA. HOWEVER... THE PARENT SURFACE HIGH SHOULD BE WELL OFF THE NORTHEAST U.S. COAST BY THIS TIME. THE NEXT SYSTEM WILL QUICKLY APPROACH FROM THE NORTHWEST. HOWEVER... THERE IS A LARGE SPREAD AMONG THE GUIDANCE IN TIMING OF THE FRONT. WPC HOLDS THE FRONT TO OUR NORTH DURING THIS TIME FRAME... GOING WITH A LESS AMPLIFIED PATTERN. GIVEN THE LOWER CONFIDENCE WILL KEEP TEMPS WITHIN A COUPLE CATEGORIES OF NORMAL AT WORST... GIVEN THE LARGE POSSIBLE SPREAD IN TEMPS. THIS YIELDS HIGHS ON TUESDAY IN THE UPPER 40S TO 50S... WITH HIGHS ON WEDNESDAY IN THE 50S TO SOME 60S... AND LOWS IN THE 30S AND 40S. && .AVIATION /12Z THURSDAY THROUGH MONDAY/... AS OF 635 AM THURSDAY... A STRONG UPPER LEVEL DISTURBANCE CROSSING CENTRAL NC EARLY THIS MORNING WILL EXIT OUR REGION BY EARLY THIS AFTERNOON. THIS SYSTEM IS TRIGGERING PATCHES OF LIGHT RAIN ACROSS THE NORTHERN PIEDMONT AND NORTHERN COASTAL PLAIN ALONG WITH VARYING CEILINGS...RESULTING IN POCKETS OF LIFR CONDITIONS. CEILINGS ARE EXPECTED TO LIFT AND DISSIPATE FROM THE SW LATER THIS MORNING...LEADING TO IMPROVING AVIATION CONDITIONS. AFTER 14Z...WEST TO NW SFC WINDS WILL BE BLUSTERY WITH GUSTS 18-23 KTS LIKELY. THE GUSTS WILL BECOME LESS LIKELY AFTER 22Z...THOUGH A STEADY NW WIND AROUND 10KTS EXPECTED WELL INTO TONIGHT. HIGH PRESSURE WILL BUILD INTO CENTRAL NC TONIGHT AND SETTLE OVERHEAD FRIDAY THROUGH SATURDAY...PROVIDING A PERIOD OF VFR CONDITIONS WITH SFC WINDS LESS THAN 10KTS. THE HIGH WILL SHIFT OFFSHORE SUNDAY. THE RESULTING SOUTH-SOUTHWEST LOW LEVEL FLOW WILL ADVECT MOISTURE INTO OUR REGION BY LATE SUNDAY- SUNDAY NIGHT LEADING TO THE POTENTIAL FOR AREAS OF MVFR FOG OR IFR CEILINGS IN STRATUS BY EARLY MONDAY. && .RAH WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...HARTFIELD NEAR TERM...HARTFIELD/WSS SHORT TERM...WSS/BSD LONG TERM...BSD AVIATION...WSS

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