Area Forecast Discussion
Issued by NWS Raleigh/Durham, NC

Current Version | Previous Version | Text Only | 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
-- Remove Highlighting --
-- Discussion containing changed information from previous version are highlighted. --
000 FXUS62 KRAH 191735 AFDRAH AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE RALEIGH NC 135 PM EDT SUN OCT 19 2014 .SYNOPSIS...
-- Changed Discussion --
.HIGH PRESSURE WILL SETTLE OVER NC AND VA TONIGHT. THE HIGH WILL DRIFT OFFSHORE MON...AHEAD OF AN UPPER LEVEL TROUGH THAT WILL MOVE INTO OUR REGION MON NIGHT.
-- End Changed Discussion --
&& .NEAR TERM /THROUGH TONIGHT/... AS OF 1045 AM SUNDAY... SUBSIDENCE IN THE WAKE OF AN EXITING S/W WILL MAINTAIN SUNNY SKIES THIS AFTERNOON ACROSS CENTRAL NC. 12Z UPPER AIR ANALYSIS DEPICTS 850MB THERMAL TROUGH OVER THE REGION THOUGH MODEL TEMPERATURE PROJECTIONS AT GSO TOO COOL BY 3-4 DEGREES C. THERMAL TROUGH WILL DRIFT EAST ACROSS THE REGION THIS AFTERNOON. THIS SCENARIO USUALLY SUPPORTS COOLER MAX TEMPS IN THE NE AND WARMER TEMPS IN THE SW. THICKNESSES THIS AFTERNOON RANGE FROM THE 1340S NE TO 1355-1360 SW...SUPPORTIVE OF HIGH TEMPS IN THE MID-UPPER 60S. AS THE MID LEVEL TROUGH MOVES FARTHER OFFSHORE AND HIGH PRESSURE BUILDS INTO THEN SETTLES OVER OUR REGION TONIGHT...EXPECT BREEZY NLY WINDS LATE THIS MORNING TO GRADUALLY SUBSIDE THIS AFTERNOON. -WSS TONIGHT: THE APPROACH OF A DEAMPLIFYING UPPER WAVE THAT WAS LOCATED OVER WESTERN OK THIS MORNING...AND A COMPLEX UPPER TROUGH AMPLIFYING SOUTHEASTWARD FROM CENTRAL CANADA...WILL RESULT IN INCREASING HIGH CLOUDS FROM THE WEST...PARTICULARLY AFTER MIDNIGHT. WITH THE CENTER OF THE SURFACE HIGH EXPECTED TO BE DIRECTLY OVERHEAD...CALM AND INITIALLY IDEAL RADIATIONAL COOLING CONDITIONS WILL SUPPORT QUICKLY FALLING TEMPERATURES AFTER SUNSET...WITH A SLOWER FALL OR NEUTRAL TENDENCY AS THE CIRRUS SPREAD EAST LATE. PROJECTED 12Z MON LOW LEVEL THICKNESSES BETWEEN 1345-1350 METERS SHOULD SUPPORT LOWS MOSTLY IN THE MIDDLE AND UPPER 30S...TO AROUND 40 DEGREES IN URBAN AREAS...SUPPORTIVE OF PATCHY FROST IN THE TYPICALLY COOLER AREAS. -MWS && .SHORT TERM /MONDAY AND MONDAY NIGHT/... AS OF 340 AM SUNDAY... SURFACE HIGH PRESSURE WILL MOVE OFFSHORE...AS THE HEIGHT FALLS ALOFT ATTENDING THE UPPER TROUGH AMPLIFYING OUT OF CENTRAL CANADA SPREAD SOUTHEASTWARD. RETURN FLOW AROUND THE HIGH WILL PROMOTE BOTH MODERATING TEMPERATURES AND INCREASING STRATOCUMULUS...THE LATTER MOST NOTABLY EAST OF INTERSTATE 95. CONSIDERABLE HIGH CLOUDS ARE ALSO EXPECTED...AS THE UPPER JET AXIS ACCOMPANYING THE AMPLIFYING TROUGH SETTLE OVERHEAD. HIGHS ABOUT 3 DEGREES ABOVE THOSE OF SUNDAY - IN THE UPPER 60S...TO AROUND 70 DEGREES OVER THE SOUTHERN TIER. THE OVERNIGHT PASSAGE OF A LEAD MID LEVEL TROUGH AND ASSOCIATED MID LEVEL MOIST AXIS MON NIGHT WILL RESULT IN A BAND OF MID CLOUDS AND VIRGA...BUT A STILL VERY DRY AIRMASS BELOW 10 THOUSAND FT SHOULD PRECLUDE ANY PRECIPITATION FROM REACHING THE GROUND. NOT AS COOL...WITH LOWS MAINLY IN THE UPPER 40S. && .LONG TERM /TUESDAY THROUGH SATURDAY/... AS OF 315 AM SUNDAY... SHORTWAVE ENERGY CURRENTLY OVER THE CANADIAN ROCKIES WILL DIVE THROUGH THE MIDWEST AND CROSS THE AREA EARLY TUESDAY...IMMEDIATELY FOLLOWED BY ANOTHER WAVE...AND ITS ASSOCIATED COLD FRONT...DIGGING THROUGH THE DEEPENING LONGWAVE TROUGH TUESDAY EVENING. DURING THE DAY...A WEST-SOUTHWESTERLY WIND AND LIMITED CLOUD COVER AHEAD OF THE COLD FRONT WILL ALLOW TEMPS TO WARM BACK INTO THE UPPER 60S AND LOWER 70S. AS THE COLD FRONT MOVES THROUGH TUESDAY EVENING...A SHOT OF STRONG DCVA WILL HAVE TO OVERCOME LIMITED MOISTURE...PW BELOW 0.75"...IN ORDER TO TO SQUEAK OUT A FEW ISOLATED...LIGHT SHOWERS...MAINLY ACROSS THE FAR NORTHERN COASTAL PLAIN WHERE MOISTURE PROFILES ARE SLIGHTLY MORE CONDUCIVE FOR PRECIP. HOWEVER...MODELS ARE ONLY GENERATING A HUNDREDTH OR TWO OF QPF IN SPOTS...SO SLIGHT CHANCE POPS CONTINUE TO BE THE BEST BET. BEHIND THE FRONT...A NORTHWESTERLY WIND WILL PERSIST THROUGH MOST OF THE WEEK AS THE UPPER TROUGH CLOSES OFF INTO AN UPPER LOW OVER THE MID-ATLANTIC COAST. MODELS HAVE HINTED AT A FEW SHOWERS ON WEDNESDAY AFTERNOON AS THE CORE OF THE COLD AIR ALOFT AND SOME VERY WEAK INSTABILITY DEVELOPS. HOWEVER...MOISTURE WILL STILL EB SEVERELY LACKING AND JUST ENHANCE CLOUD COVER SEEMS MORE LIKELY. THICKNESSES ARE FORECAST TO BRIEFLY TOUCH 1340M ON WEDNESDAY MORNING...THEN CLIMB BACK TOWARD NORMAL VALUES AROUND 1360M BY THE END OF THE WEEK AS THE UPPER BEGINS TO DRIFT NORTHEAST AWAY FROM THE REGION. THUS...HIGHS WILL BE COOLEST WEDNESDAY IN THE LOW TO MID 60S AND TREND BACK INTO THE UPPER 60S TO LOWER 70S. THERE ARE SIGNIFICANT MODEL DIFFERENCES BY NEXT WEEKEND AS ENERGY CROSSING THE CENTRAL US IS FORCED INTO THE DEEP SOUTH AND THEN EITHER MOVES EAST ACROSS THE SOUTHEAST US (GFS SOLUTION) OR CUTS OFF OVER THE GULF COAST (ECMWF SOLUTION). WPC HAS A STRONG PREFERENCE FOR THE ECMWF AND ITS ENSEMBLE MEAN. EITHER WAY THE FORECAST WILL REMAIN DRY AND NEAR NORMAL THROUGH THE END OF THE EXTENDED PERIOD. && .AVIATION /18Z SUNDAY THROUGH FRIDAY/...
-- Changed Discussion --
AS OF 135 PM SUNDAY... A DRY AND STABLE AIR MASS OVER CENTRAL NC WILL RESULT IN VFR CONDITIONS THROUGH TUESDAY. AN AREA OF HIGH PRESSURE WILL SETTLE OVERHEAD TONIGHT THEN DRIFT EAST ON MONDAY. RETURN SLY FLOW WILL BEGIN TO ADVECT LOW LEVEL MOISTURE INTO OUR REGION...RESULTING IN SCATTERED CUMULUS...MAINLY IN VICINITY OF KFAY. THRE IS A GOOD CHANCE THAT VFR CONDITIONS WILL PREVAIL TUESDAY THROUGH FRIDAY. A SERIES OF S/W ROTATING AROUND A CLOSED UPPER LEVEL LOW OVER THE NORTHERN MID ATLANTIC WILL CAUSE PERIODS OF CLOUDINESS OVER CENTRAL NC TUESDAY THROUGH WEDNESDAY NIGHT. HOWEVER CLOUD BASES SHOULD REMAIN ABOVE MVFR CRITERIA. THE UPPER LEVEL LOW WILL LIFT GRADUALLY NEWD THU INTO FRIDAY...ALLOWING HIGH PRESSURE TO BUILD INTO OUR REGION.
-- End Changed Discussion --
&& .RAH WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...WSS/MWS NEAR TERM...WSS/MWS SHORT TERM...MWS LONG TERM...BLS AVIATION...WSS

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