Area Forecast Discussion
Issued by NWS Raleigh/Durham, NC

Current Version | Previous Version | Graphics & Text | Print | Product List | Glossary Off
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 102029 AFDRAH AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE RALEIGH NC 329 PM EST WED FEB 10 2016 .SYNOPSIS...A DEEP UPPER LEVEL TROUGH WILL PERSIST OVER THE EASTERN UNITED STATES TODAY THROUGH THURSDAY. AN UPPER LEVEL DISTURBANCE WILL CROSS THE SOUTHEAST STATES LATE THURSDAY THROUGH FRIDAY. ARCTIC HIGH PRESSURE WILL BUILD IN FROM THE NORTHWEST LATE FRIDAY THROUGH THE WEEKEND. A STORM SYSTEM WILL AFFECT THE REGION NEXT MONDAY. && .NEAR TERM /THROUGH THURSDAY NIGHT/... AS OF 330 PM WEDNESDAY... THROUGH TONIGHT: THE AXIS OF A 500 MB TROUGH CONTINUES TO PASS THROUGH THE AREA THIS AFTERNOON WITH A FAIRLY STRONG PRESSURE GRADIENT FEATURING WEST NORTHWESTERLY SURFACE FLOW ACROSS THE CWA. BECAUSE OF THIS GRADIENT COMBINED WITH A FAIRLY DEEP MIXED LAYER...THE MAIN WEATHER STORY THIS AFTERNOON HAS BEEN SOME BREEZY WINDS WITH MOST LOCATIONS OUT OF THE WEST NORTHWEST AT 10 KTS GUSTING TO 20 KTS. THESE GUSTS SHOULD BEGIN TO SUBSIDE AFTER SUNSET BUT SUSTAINED WINDS WILL REMAIN 5-10 KTS OVERNIGHT TONIGHT. CLOUDS THAT HAVE DEVELOPED THIS AFTERNOON IN ASSOCIATION WITH THE PASSING SHORTWAVE WILL MOVE OFF TO THE EAST LATER...PROMOTING SOME CLEARING FROM THE WEST OVERNIGHT BUT INTERMITTENT CLOUDS WILL REMAIN. THIS ALONG WITH SOME WINDS OVERNIGHT WILL KEEP IDEAL RADIATIONAL COOLING CONDITIONS FROM FORMING BUT NONETHELESS WITH A VERY COLD AIRMASS IN PLACE...UPPER TEENS TO LOW 20S SHOULD BE EASILY ATTAINABLE OVERNIGHT TONIGHT AND INTO THURSDAY MORNING. THURSDAY AND THURSDAY NIGHT: THE UPPER TROUGH WILL BEGIN TO RELAX AS THE SURFACE LOW PRESSURE SYSTEM OFF OF NEW ENGLAND CONTINUES OUT TO SEA. THICKNESSES WILL TAKE A WHILE TO RECOVER HOWEVER AND THE WARMER THICKNESSES WILL REMAIN TO OUR SOUTH. THEREFORE NOT MUCH CHANGE IN HIGH TEMPERATURE FOR THURSDAY WITH UPPER 30S TO LOWER 40S ACROSS THE AREA. SKIES WILL BE MOSTLY CLEAR WITH PLENTY OF SUN HOWEVER WITH BUT STILL A LITTLE BREEZY WITH GUSTS UP TO 15 KTS OR SO. THURSDAY NIGHT WILL FEATURE A GRADIENT IN THE LOW TEMPERATURE FROM NORTH TO SOUTH WITH UPPER TEENS NORTH TO MIDDLE 20S SOUTH AS A LOW PRESSURE SYSTEM BEGINS TO DEVELOP SOUTH OF THE AREA LATE THURSDAY NIGHT INTO FRIDAY MORNING. && .SHORT TERM /FRIDAY AND FRIDAY NIGHT/... AS OF 230 PM WEDNESDAY... WITH THE LONGWAVE TROUGH HOLDING OVER ERN NOAM... A PERTURBATION NOW COMING INTO THE PACIFIC NORTHWEST WILL RIDE ATOP THE WESTERN RIDGE AND SHEAR OUT AS IT DIVES INTO THE TROUGH BASE AND EVENTUALLY CROSSES THE CAROLINAS FRI GENERATING WEAK DPVA. THE FORCING FOR ASCENT WITH THIS FEATURE WILL BE AUGMENTED BY UPPER DIVERGENCE IN THE LEFT EXIT REGION OF THE JET DIVING INTO THE CENTRAL CONUS TOWARD THE SOUTHEAST STATES... AND THIS WILL SUPPORT SURFACE LOW PRESSURE DEVELOPMENT... TRACKING ACROSS AR AND THE GULF STATES/SRN GA/SRN SC THU/THU NIGHT BEFORE SHIFTING OFF THE SC COAST FRI MORNING. THE OVERALL LIFT IS NOT TERRIBLY IMPRESSIVE HOWEVER... AND THE LATEST MODEL RUNS DO NOT SUBSTANTIALLY DEEPEN THE SURFACE LOW UNTIL IT IS ALREADY WELL OFF THE COAST AND MOVING ENE AWAY FROM NC... KEEPING IT RATHER WEAK AND FLAT WITHOUT A STRONG THERMAL ADVECTION PATTERN. MOISTURE IS ALSO UNIMPRESSIVE... WITH FORECAST SOUNDINGS INDICATING MULTIPLE UNSATURATED LAYERS AND INCONSISTENT MOISTENING ABOVE -10C THAT BRINGS DOUBT AS TO THE PRESENCE OF ICE ALOFT. WITH MODELS CONTINUING TO DEPICT VERY LIGHT TO NO QPF EXCEPT AS ONE GETS CLOSER TO THE CENTRAL COASTAL AREA... WILL TAKE POPS AND AMOUNTS DOWNWARD OVER MUCH OF THE CWA. THICKNESSES AND THE VERTICAL THERMAL STRUCTURES NOTED ON FORECAST SOUNDINGS SUPPORT A MOSTLY RAIN/SNOW MIX OVER THE FAR SE CWA... AND WHILE THIS IS THE AREA THAT IS MOST LIKELY TO SEE SOME SLIGHTLY HEAVIER BANDED PRECIP ON THE NW SIDE OF THE DEPARTING LOW... THE HIGH PROBABILITY OF A MIXTURE WILL KEEP ANY ACCUMULATIONS VERY LOW... WITH ONLY A SLUSHY COATING AT MOST. FURTHER INLAND... WITHIN THE COLDER THICKNESSES... ANY PRECIP SHOULD BE LIGHT FLURRIES... YIELDING LITTLE MORE THAN A LIGHT DUSTING WITH NO TRAVEL IMPACTS. EXPECT CONSIDERABLE CLOUD COVER FRI... WITH CLEARING FRI NIGHT AS THE POLAR FRONT DROPS SOUTHEAST THROUGH THE AREA... MOST LIKELY OCCURRING AFTER MIDNIGHT. HIGHS 36-42 FRI AND LOWS 21-28. -GIH && LONG TERM /SATURDAY THROUGH TUESDAY/... AS OF 330 AM WEDNESDAY... ...A SECONDARY COLDER INTRUSION OF ARCTIC AIR WILL DESCEND SOUTH INTO THE REGION THIS WEEKEND... SATURDAY THROUGH SUNDAY: MODELS ARE IN GOOD AGREEMENT THAT THIS SECONDARY INTRUSION OF ARCTIC AIR WILL BE EVEN COLDER THE EARLY/MID WEEK INSTALLMENT. ANCHORED BY A STRONG ~1040MB ARCTIC HIGH PRESSURE...TEMPERATURES THIS WEEKEND WILL AVERAGE 20 TO 25 DEGREES BELOW NORMAL...WITH A GOOD CHANCE THAT TEMPERATURES VALENTINES DAY WILL REMAIN AT OR BELOW FREEZING WITH NIGHTTIME LOWS IN THE SINGLE DIGITS TO LOW TEENS. MONDAY AND TUESDAY: ARCTIC HIGH WILL RETREAT OFF THE MID-ATLANTIC COAST ON MONDAY. A PROGRESSIVE SHORTWAVE TRACKING EASTWARD FROM THE CENTRAL PLAINS MOVES WILL RESULT IN STRENGTHENING WARM MOIST ADVECTION INTO THE REGION FROM THE WEST MONDAY-TUESDAY. WITH ANTECEDENT ARCTIC AIRMASS IN PLACE...STRONG WAA ALOFT INTO A INSITU WEDGE WOULD RESULT IN MIXED P-TYPE CONCERNS ACROSS THE CAROLINA PIEDMONT...WITH EARLY INDICATORS THAT THE CLIMATOLOGICALLY FAVORED AREA NW PIEDMONT COULD SEE A SIGNIFICANT ICING EVENT. RESIDENTS OF CENTRAL NC SHOULD CLOSELY MONITOR FORECAST TRENDS OVER THE NEXT SEVERAL DAYS. && .AVIATION /12Z THROUGH MONDAY/... AS OF 105 PM WEDNESDAY... 24 HOUR TAF PERIOD: HIGH CONFIDENCE OF VFR CONDITIONS THROUGH THE TAF PERIOD. WIND GUSTS WILL BE THE ISSUE OF THE DAY AS WEST NORTHWESTERLY WINDS AT 10 KTS GUSTING 15-20 KTS WILL BE POSSIBLE AT ALL TAF SITES TODAY. WINDS WILL REGRESS AFTER SUNSET BUT WILL SHOW UP AGAIN AFTER 15Z THURSDAY. WITH DRY AIR IN PLACE...FOG OR LOW STRATUS SHOULD NOT BE A PROBLEM OVERNIGHT. MAY SEE SOME MIDDLE TO HIGH CEILINGS LATER IN THE DAY BUT NOTHING TO POSE A THREAT TO AVIATION CONDITIONS. LONG TERM: A COASTAL SYSTEM ON FRIDAY WITH A SHORTWAVE MOVING ACROSS THE NORTH WILL BRING A CHANCE FOR SUB-VFR CONDITIONS PARTICULARLY AT EASTERN TAF SITES. THE NEXT MORE SIGNIFICANT SYSTEM IS PROGGED TO ENTER THE REGION MONDAY NIGHT INTO TUESDAY. && .CLIMATE... HERE ARE THE RECORD LOWS AND RECORD LOW MAXIMUM TEMPERATURES FOR SAT FEB 13TH AND SUN FEB 14TH AT GSO... RDU... AND FAY: REC YR REC YR LOW LOW MAX ---------------------------------------------- GSO: 02/13 11 1955 31 1986 02/14 6 1905 22 1914 RDU: 02/13 4 1899 10 1899 02/14 -2 1899 27 1916 FAY: 02/13 14 1973 32 1955 02/14 12 1968 33 1916 && .RAH WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...HARTFIELD NEAR TERM...ELLIS SHORT TERM...HARTFIELD LONG TERM...CBL AVIATION...ELLIS CLIMATE...HARTFIELD

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