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 230705 AFDRAH AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE RALEIGH NC 300 AM EDT THU OCT 23 2014 .SYNOPSIS...A STRONG UPPER LEVEL LOW OVER THE MID ATLANTIC COAST SLOWLY TRACK NORTHEAST AND OFFSHORE TODAY. HIGH PRESSURE WILL BUILD INTO THE REGION FROM THE WEST THROUGH SATURDAY. && .NEAR TERM /THROUGH TONIGHT/...
-- Changed Discussion --
AS OF 300 AM THURSDAY... THE UPPER LOW SPINNING OFF THE MID-ATLANTIC COAST WILL LIFT NORTHEASTWARD AND AWAY FROM THE REGION TODAY. NORTHWEST FLOW WILL CONTINUE OVER NC...THOUGH WEAKENING AS THE PRESSURE GRADIENT RELAXES...WITH VERY DRY AIR EAST OF THE MOUNTAINS. A FEW WIND GUSTS ARE STILL POSSIBLE...ESPECIALLY THIS MORNING AND ACROSS THE COASTAL PLAIN. THE 850MB THERMAL TROUGH WILL SHIFT EAST OF THE AREA AND THICKNESSES WILL START ABOUT 5M HIGHER THAN YESTERDAY...SUPPORTING HIGHS A DEGREE OR TWO WARMER IN THE 66-70 RANGE. TONIGHT...A DEAMPLIFYING SHORTWAVE CROSSING THE MID-MISSISSIPPI RIVER VALLEY WILL LIKELY SPREAD SOME CIRRUS ACROSS THE AREA AFTER MIDNIGHT. CURRENTLY...IT DOESNT APPEAR THE CIRRUS WILL BE VERY THICK...BUT IF IT IS THEN FORECAST LOWS OF 40-43 MAY BE TOO COLD.
-- End Changed Discussion --
&& .SHORT TERM /FRIDAY AND FRIDAY NIGHT/...
-- Changed Discussion --
AS OF 300 AM THURSDAY.. HIGH PRESSURE WILL EXTEND INTO THE AREA FORM THE DEEP SOUTH FRIDAY ...WITH A DISTURBANCE POISED TO DIVE FROM THE UPPER MIDWEST ACROSS THE CAROLINAS FRIDAY NIGHT. WITH VERY LITTLE DEEP MOISTURE TO INTERACT WITH...THE SHORTWAVE WILL CROSS THE AREA RELATIVELY UNNOTICED. THICKNESSES RISE ANOTHER 10M BY FRIDAY MORNING...YIELDING HIGHS IN THE LOWER 70S. LOWS SATURDAY NIGHT IN THE MID 40S.
-- End Changed Discussion --
&& .LONG TERM /SATURDAY THROUGH TUESDAY/... AS OF 235 AM THURSDAY... FOR SAT-SUN NIGHT: AS THE MID LEVEL SHORTWAVE TROUGH AXIS MOVES EAST OF THE FORECAST AREA EARLY SAT MORNING... A BENIGN WEST-TO-EAST- MOVING WARM FRONT WILL SHIFT THROUGH THE AREA SAT WITH LIGHT SURFACE FLOW BACKING FROM NW TO WSW. GIVEN THE DRY AND STABLE AIR ON FORECAST SOUNDINGS AND SURFACE HIGH PRESSURE RIDGE NOSING NORTHEASTWARD INTO NC... EXPECT LITTLE MORE THAN SCTD FLAT CUMULUS SAT. A FAST-MOVING AND WEAK COLD FRONT IS THEN EXPECTED TO DROP INTO NC FROM THE NW LATE SAT NIGHT... A RESULT OF STRONG VORTICITY SWEEPING ACROSS THE NRN GREAT LAKES ON THE SOUTH SIDE OF A MID LEVEL LOW THAT WILL MOVE FROM SRN ONTARIO ACROSS SE QUEBEC THROUGH SUN MORNING. WE MAY SEE A PERIOD OF BROKEN CLOUDS WITH THE COLD FRONT PASSAGE... BUT IT WILL REMAIN DRY AS THE EFFECTS OF THE COLD FRONT WILL BE MUTED BY THE LACK OF MOISTURE AS WELL AS THE SUPPRESSION OF THE (ELEVATED) LIFT TO OUR NORTH. AND THE LATEST GFS/ECMWF SHOW LITTLE TO NO DROP IN THICKNESSES... WITH THE FRONT JUST BRUSHING ACROSS NRN NC. THE GFS IN PARTICULAR HOLDS ALL COOLER AIR NORTH OF THE BORDER AND KEEPS CENTRAL NC THICKNESSES 20-30 M ABOVE NORMAL. EVEN THE MORE SUBDUED ECMWF HAS TRENDED MILDER. SO... EXPECT SATURDAY`S SLIGHTLY ABOVE NORMAL HIGHS IN THE LOW-MID 70S TO HOLD FIRM FOR SUNDAY AS WELL... AND COULD EVEN BE A COUPLE DEGREES WARMER ACROSS SRN NC. LOWS IN THE UPPER 40S TO NEAR 50 SAT NIGHT. EXPECT TEMPS TO BE A TAD COOLER SUN NIGHT... LOW-MID 40S... AS HIGH PRESSURE BUILDS INTO AND OVER NC FROM THE NW... ALLOWING FOR GOOD RADIATIONAL COOLING WITH A LACK OF CLOUDS AND A DROPOFF OF WINDS OVERNIGHT. FOR MON-WED: DRY AND WARMING. THE MID LEVEL LOW OVER THE ST LAWRENCE VALLEY AND NORTHEAST STATES WILL MOVE OVER AND OFF THE CANADIAN MARITIMES... AS MID LEVEL RIDGING BUILDS FROM THE SRN PLAINS EASTWARD TO OVER AND JUST OFF THE SOUTHEAST COAST THROUGH WED. AS THE SURFACE... THE HIGH OVERHEAD SUN NIGHT WILL EASE SLOWLY OFF THE COAST WITH INCREASING THICKNESSES THROUGH MID WEEK. THE GFS/ECMWF TAKE A LONGWAVE TROUGH THROUGH THE PLAINS AND INTO THE GREAT LAKES TUE/WED WITH A CORRESPONDING SURFACE COLD FRONT... HOWEVER THERE IS MUCH UNCERTAINTY REGARDING THE SPEED OF APPROACH OF THIS TROUGH AND FRONT TOWARD NC. WILL MAINTAIN TEMPS A BIT ABOVE-NORMAL AND A TREND TOWARD INCREASING CLOUDS AS LOW LEVEL FLOW INTRODUCES GRADUALLY IMPROVING MOISTURE... BUT WITH NO APPRECIABLE RAIN IN SIGHT. -GIH && .AVIATION /06Z THURSDAY THROUGH MONDAY/... AS OF 145 AM THURSDAY... NORTHWESTERLY FLOW ON THE SOUTHERN FRINGE OF AN UPPER LOW OFF THE MID-ATLANTIC COAST WILL MAINTAIN VFR CONDITIONS THROUGH THE TAF PERIOD. WILL LIKELY SEE SOME WIND GUSTS INTO THE 15-20KT RANGE...ESPECIALLY THIS MORNING AND AT POINTS EATS OF KRDU...WITH A GRADUAL WEAKENING OF WINDS THROUGH THE LATE AFTERNOON AND EVENING HOURS AS THE PRESSURE GRADIENT WEAKENS. LIGHT NORTHWESTERLY WINDS ARE EXPECTED TONIGHT. OUTLOOK...A PROLONGED PERIOD OF VFR CONDITIONS WILL PERSIST INTO THE WEEKEND/EARLY NEXT WEEK AS THE WEATHER REMAINS DOMINATED BY DRY NORTHWESTERLY FLOW ALOFT AND SURFACE HIGH PRESSURE. && .RAH WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...HARTFIELD NEAR TERM...BLS SHORT TERM...BLS LONG TERM...HARTFIELD AVIATION...KRD/BLS

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