Area Forecast Discussion
Issued by NWS Raleigh/Durham, NC

Current Version | Previous Version | Text Only | 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
-- Remove Highlighting --
-- Discussion containing changed information from previous version are highlighted. --
643 FXUS62 KRAH 300754 AFDRAH AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE RALEIGH NC 350 AM EDT SAT APR 30 2016 .SYNOPSIS... A QUASI-STATIONARY FRONT --WITH COOL AND CLOUDY CONDITIONS TO THE NORTH...AND MUCH WARMER ONES TO THE SOUTH-- WILL REMAIN OVER SOUTHERN AND SOUTHWESTERN NC TODAY. THE FRONT AND ASSOCIATED FOLLOWING WARMER TEMPERATURES WILL RETREAT NORTH ACROSS THE MIDDLE ATLANTIC STATES LATE TONIGHT AND ESPECIALLY SUNDAY. WARM SOUTHWESTERLY FLOW WILL THEN RESULT THROUGH MONDAY. && .NEAR TERM /THROUGH TONIGHT/... AS OF 905 PM FRIDAY... QUIET AND DRY BUT WITH INCREASING CLOUDS AND SOME FOG POTENTIAL OVERNIGHT. LATEST ANALYSIS SHOWS THE FRONT STRETCHED ACROSS CENTRAL VA AND NE NC... POISED TO PUSH A BIT FURTHER SSW INTO NC AS OFFSHORE LOW PRESSURE OFF THE SE VA COAST DRAWS COOLER AND MORE STABLE AIR IN FROM THE NNE... WITH THE STABILIZING ASSISTANCE OF NOCTURNAL COOLING. EXPECT INCREASING AND THICKENING LOW CLOUDS PARTICULARLY ACROSS THE NORTH AND EAST CWA... WITH POCKETS OF FOG AND DRIZZLE POSSIBLE THERE. WHILE THE LOW CLOUDS MAY NOT QUITE MAKE IT INTO THE SW CWA... WE`LL ALSO SEE INCREASING MID AND HIGH CLOUDS OVER OUR SOUTH AND WEST RESULTING FROM UPPER LEVEL EVACUATION FROM THE WEAKENING AL MCS. IN SHORT... SKIES SHOULD TREND TO PARTLY CLOUDY WEST/SOUTH AND MOSTLY CLOUDY NORTH/EAST OVERNIGHT. TEMPS SHOULD CONTINUE TO FALL BUT LEVEL OFF FOR THE OVERNIGHT HOURS... YIELDING LOWS FROM THE MID 50S NW TO LOW-MID 60S SW. -GIH && .SHORT TERM /SUNDAY AND SUNDAY NIGHT/...
-- Changed Discussion --
AS OF 350 AM SATURDAY... A PORTION OF THE COMPLEX UPPER LOW OVER THE WESTERN US WILL EJECT EASTWARD AND RACE ACROSS LOWER GREAT LAKES ON SUNDAY...SHUNTING THE SHORTWAVE RIDGE OVER THE SOUTHEAST US OFFSHORE. MEANWHILE...THE FRONTAL ZONE LINGERING OVER CENTRAL NC TODAY WILL RETREAT NORTHWARD IN TO THE MID-ATLANTIC REGION. ONGOING OVER SHOWERS OVER WESTERN NC...OWING TO SOUTHEASTERLY LOW-LEVEL FLOW AND WEAK HEIGHT FALLS ALOFT...WILL LIKELY BLEED INTO THE WESTERN PIEDMONT SUNDAY MORNING...THOUGH WITHOUT BETTER SUPPORT ALOFT THE COVERAGE OF SHOWERS AND STORMS IS A LITTLE UNCERTAIN WITH EASTWARD EXTENT SUNDAY AFTERNOON. NAM/GFS FORECAST SOUNDINGS SHOW MODEST STEEPENING OF MID- LEVEL LAPSE RATES AND MLCAPE POSSIBLY REACHING 1000-1500 J/KG CAPE AMIDST PW OF 1.25-1.50". CAPE GENERALLY APPEARS TO BE HIGHER IN THE WEST..THOUGH THE DEGREE OF SURFACE HEATING IS UNCERTAIN GIVEN THE AFOREMENTIONED MORNING PRECIP/CLOUD COVER. DEEP LAYER SHEAR IS MODEST...30-35KT ACROSS THE NORTH IN CLOSER TO PROXIMITY TO THE SHORTWAVE CROSSING THE GREAT LAKES AND STRONGER MID-LEVEL FLOW. THE MAIN LIMITATION FOR SEVERE WEATHER APPEARS TO BE A LACK OF A FOCUS...OUTSIDE IF A RIPPLE IN THE FLOW ALOFT. THUS..ITS HEARD TO HAVE MORE THAN CHANCE POPS AT THIS POINT...WITH LOW CONFIDENCE IN ANY SEVERE STORMS. HIGHS IN THE MID 70S NW TO AROUND 80 SE. THE NAM AND GFS INDICATE AT LEAST A CHANCE OF LINGERING SHOWERS INT HE COASTAL PLAIN SUNDAY NIGHT AS THE DEEP LAYER FLOW VEERS TO MORE WESTERLY AND DEEP MOISTURE SHIFTS EASTWARD. LOWS 61-68 WEST TO EAST.
-- End Changed Discussion --
&& .LONG TERM /MONDAY THROUGH FRIDAY/...
-- Changed Discussion --
AS OF 350 AM SATURDAY... DEEP LAYER FLOW WILL BECOME MORE WEST-SOUTHWESTERLY ON MONDAY AS DISTURBANCES CONTINUE TO TRACK FROM THE CENTRAL PLAINS TO THROUGH THE OH VALLEY. MID-LEVEL DRYING AND STRONGER BL MIXING WILL LIMIT INSTABILITY ACROSS THE NORTHERN/WESTERN PIEDMONT...FOCUSING SCATTERED SHOWERS AND STORMS TO SOUTHERN PIEDMONT AN COASTAL PLAIN. MONDAY AFTERNOON. HOWEVER...A COLD FRONT WILL APPROACH FROM THE NORTHWEST LATE MONDAY...OFFERING A BETTER FOCUS FOR CONVECTION MONDAY NIGHT AND INTO TUESDAY...DEPENDING ON HOW FAR SOUTH THE FRONT SETTLES. FORECAST CONFIDENCE THEN FALLS FOR THE MID TO LATE WEEK PERIOD AS RIDGE BUILDS OVER THE WESTERN US AND SHORTWAVES DROPPING SOUTH OUT OF CANADA RESULT INTO A DEEP TROUGH OVER THE EASTERN US. THE EVENTUAL AMPLITUDE OF THE TROUGH IS UNCERTAIN...BUT THE EC ENSEMBLE SUGGESTS 2-3 STD BELOW NORMAL OVER THE DEEP SOUTH AND THE OPERATIONAL GFS SETTLES AN UPPER LOW OVER THE CAROLINAS BY THE END OF THE WEEK. THIS PATTERN SUGGESTS PERIODS OF SHOWERS WILL CONTINUE TO BE POSSIBLE...WITH A SURFACE LOW LIKELY TO DEVELOP OFF THE SOUTHEAST COAST BY THURSDAY...AND DAILY HIGHS AT LEAST A COUPLE CATEGORIES BELOW NORMAL...IF NOT MORE.
-- End Changed Discussion --
&& .AVIATION /07Z SATURDAY THROUGH WEDNESDAY/... AS OF 200 AM SATURDAY... IFR TO MVFR RANGE STRATUS (600-2000 FT) --IN NORTHEASTERLY LOW LEVEL FLOW ON THE COOL SIDE OF A SURFACE FRONT OVER WEST-CENTRAL NC-- WILL CONTINUE TO EXPAND SOUTHWESTWARD ACROSS CENTRAL NC THIS MORNING. THIS FRONTAL ZONE WILL SEPARATE LOW OVERCAST TO THE NORTH FROM WARM VFR CONDITIONS AND A CHANCE OF THUNDERSTORMS ALONG AND SOUTH OF THE FRONT. ALL CENTRAL NC TAF SITES ARE EXPECTED TO REMAIN ON THE COOL/CLOUDY SIDE OF THE BOUNDARY TODAY...WITH MERELY A GRADUAL RISE OF SUB-VFR CEILINGS INTO THE 1500-2500 FT RANGE THIS AFTERNOON. HOWEVER...SOME EROSION OF THE LOW CLOUDS FROM THE EDGES MAY LEAD TO A BRIEF SCATTERING TO VFR --MOST LIKELY AT FAY AND RWI-- FOR A FEW HOUR PERIOD THIS AFTERNOON AND EVENING. A FEW SHOWERS MAY ALSO AFFECT TRIAD TAF SITES THIS AFTERNOON. CEILINGS WILL OTHERWISE LOWER ONCE AGAIN OVERNIGHT...ALONG WITH THE ARRIVAL OF SHOWERS AND PERHAPS A FEW THUNDERSTORMS AT PIEDMONT TAF SITES THROUGH EARLY SUNDAY. OUTLOOK: A SERIES OF WAVES OF LOW PRESSURE WILL TRACK ALONG A STALLED FRONTAL ZONE ALONG THE SOUTHEAST UNITED STATES COAST...WITH ASSOCIATED PERIODS OF RAIN AND SUB-VFR CONDITIONS OVER CENTRAL NC...MON NIGHT THROUGH WED. && .RAH WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...MWS NEAR TERM...HARTFIELD SHORT TERM...22 LONG TERM...22 AVIATION...MWS

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