000
FXUS62 KRAH 260438
AFDRAH

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RALEIGH NC
1240 AM EDT SUN OCT 26 2014

.SYNOPSIS...A WEAK COOL FRONT WILL DROP SOUTH INTO NORTHERN NORTH
CAROLINA TODAY... AS HIGH PRESSURE DRIFTS EAST ACROSS THE SOUTHEAST
STATES. THIS HIGH WILL MOVE OFF THE COAST ON MONDAY... AS THE FRONT
MOVES BACK NORTH AS A WARM FRONT. THE RESULTING SOUTHWEST FLOW WILL
BRING IN MUCH WARMER AIR FOR TUESDAY. A COLD FRONT WILL APPROACH
FROM THE WEST ON WEDNESDAY.

&&

.NEAR TERM /THROUGH SUNDAY NIGHT/...
AS OF 955 PM SATURDAY...

WHILE NOT A CRITICAL FORECAST...A CHALLENGING FORECAST JUST THE SAME
AS DIFFERENCE IN A LITTLE WIND/MIXING AND A VERY DRY AIR MASS
CREATING A WIDE VARIANCE IN TEMPS ACROSS THE REGION THIS EVENING.

WHERE A STEADY SWLY WIND OCCURRING...EVENING TEMPS IN THE UPPER 50S-
LOWER 60S COMMON. CONVERSELY WHERE THE SFC WIND HAS
DECOUPLED...TEMPS IN THE 40S TO AROUND 50 BEING REPORTED. THE
APPROACH OF A SURFACE FRONT FROM THE NW OVERNIGHT SHOULD CAUSE A
LIGHT SW-WLY FLOW TO OCCUR OVER THE WESTERN PIEDMONT. FARTHER EAST
OVER SECTIONS OF THE SANDHILLS AND COASTAL PLAIN...BETTER CHANCE OF
SEEING SFC WINDS BECOME CALM. THUS...EXPECT COOLEST MIN TEMPS TO
OCCUR OVER THE SOUTH AND EAST SECTIONS OF THE FORECAST AREA...WHILE
WARMEST MIN TEMPS WILL BE IN THE URBAN CENTERS AND THE WESTERN
PIEDMONT. MIN TEMPS MID 40S EAST-LOWER 50S WEST-NW. -WSS


SUN/SUN NIGHT: THE UPPER LEVEL LOW DIGGING INTO NEW ENGLAND LATE
TONIGHT WILL LIFT NORTHEAST INTO THE CANADIAN MARITIMES SUN/SUN
NIGHT. MEANWHILE...AN UPSTREAM RIDGE OVER THE CENTRAL CONUS WILL
PROGRESS EASTWARD THROUGH THE TN/OH VALLEY TO THE WESTERN SLOPES OF
THE APPALACHIANS BY 12Z MON. COLD ADVECTION IS EXPECTED ACROSS
CENTRAL NC SUN MORNING IN THE WAKE OF A DRY COLD FRONT TRAILING THE
POTENT UPPER LEVEL LOW DIGGING INTO NEW ENGLAND. COLD ADVECTION WILL
BE SHORT-LIVED IN MOST LOCATIONS...HOWEVER...AS WARM ADVECTION
ATTENDANT THE ADVANCING UPPER LEVEL RIDGE RETURNS BY EARLY AFTERNOON
IN ALL AREAS EXCEPT THE NE COASTAL PLAIN. GIVEN THAT MOS GUIDANCE
HAS BEEN CONSISTENTLY TOO WARM THE PAST SEVERAL DAYS...HAVE OPTED TO
DECREASE HIGHS A FEW DEGREES FROM THE PRIOR FORECAST TO THE LOW/MID
70S...COOLEST IN THE NE COASTAL PLAIN...WITH A NORTHWEST BREEZE AT
~15 MPH GUSTING UP TO 25 MPH. HIGH PRESSURE WILL BUILD OVER CENTRAL
NC/VA FROM THE WEST SUN NIGHT. GIVEN CLEAR SKIES/CALM WINDS AND A
DRIER AIRMASS ADVECTING INTO THE AREA IN THE WAKE OF THE DRY FRONTAL
PASSAGE EARLIER IN THE DAY...EXPECT GOOD RADIATIONAL COOLING WITH
LOWS IN THE LOW/MID 40S. -VINCENT

&&

.SHORT TERM /MONDAY THROUGH WEDNESDAY NIGHT/...
AS OF 315 PM SATURDAY...

WARM AND DRY MONDAY INTO WEDNESDAY...

THE SURFACE HIGH PRESSURE IS FORECAST TO SHIFT OFFSHORE MONDAY
AFTERNOON AND NIGHT. THIS WILL GRADUALLY ALLOW A SW FLOW TO RETURN
TO THE REGION BY LATE MONDAY AND ESPECIALLY BY TUESDAY. SINCE THE
STRONGEST WAA IS EXPECTED TUESDAY... THAT WILL LIKELY BE THE WARMEST
DAY THIS UPCOMING PERIOD. HIGHS MONDAY SHOULD REACH THE MID 70S WITH
UPPER 70S TO NEAR 80 OVER THE SANDHILLS. LOWS WILL BE IN THE MID 40S
TO LOWER 50S MONDAY... WARMING INTO THE LOWER TO MID 50S TUESDAY AND
WEDNESDAY. HIGHS WEDNESDAY SHOULD BE TEMPERED BY SOME INCREASE IN
CLOUDS (EXPECT MOSTLY MID TO UPPER 70S).

&&

.LONG TERM /THURSDAY THROUGH SATURDAY/...
AS OF 315 PM SATURDAY...

...INCREASING ODDS OF THE FIRST FREEZE BY NEXT WEEKEND...

...PATTERN CHANGE TO COLDER WEATHER FROM THE GREAT LAKES TO THE SE
COAST LATE IN THE WEEK...

WHILE OPERATIONAL MODELS CONTINUE TO SHOW LARGE SPREAD OF SOLUTIONS
FOR OUR REGION MID TO LATE WEEK... THEY HAVE BEEN TRENDING TOWARD A
DEEPER AND COLDER UPPER TROUGH DEVELOPMENT FROM THE GREAT LAKES TO
THE TENNESSEE VALLEY TO THE EAST COAST BY FRIDAY AND SATURDAY. THIS
WOULD ALLOW A GOOD PUSH OF CONTINENTAL POLAR AIR... DRIVEN BY A
1035+ SURFACE HIGH PRESSURE... TO DIVE INTO THE CENTRAL AND EASTERN
STATES FRIDAY AND SATURDAY. WHILE A LOT IS YET TO BE DETERMINED
LIKELY DRIVEN BY THE REMNANTS OF ANA AS IT DRIVES INTO THE ALASKA
PANHANDLE. THE EUROPEAN AND ITS ENSEMBLES INDICATE A DEEPER AND MORE
CUT OFF MID/UPPER TROUGH OVER OUR REGION BY SAT-SUN... WHILE THE GFS
IS NOT AS STRONG. REGARDLESS... A BLEND OF THE ENSEMBLES AND TRENDS
STRONGLY SUGGEST AT LEAST A ROBUST MID/UPPER TROUGH OVER THE EASTERN
STATES. THE MORE EXTREME EUROPEAN MAY STILL DEVELOP... BUT IS STILL
CONSIDERED A LOW PROBABILITY AT THIS TIME.

THE BOTTOM LINE... THE PROBABILITY OF THE FIRST KILLING FROST OR
FREEZE FOR OUR REGION IS INCREASING FOR NEXT WEEKEND. HIGHS MAY
REMAIN IN THE 50S BY SATURDAY... WITH LOWS BY SATURDAY NIGHT
POTENTIALLY ENDING THE GROWING SEASON FOR MOST OF OUR WESTERN AND
NORTHERN ZONES IF NOT MORE OF THE REGION.

&&

.AVIATION /06Z SUNDAY THROUGH THURSDAY/...
AS OF 1240 AM SUNDAY...

CONFIDENCE IS HIGH THAT VFR CONDITIONS WILL PERSIST AT ALL CENTRAL
NC TERMINAL FORECAST SITES TODAY THROUGH TONIGHT. DEEPLY DRY AND
STABLE AIR OVERHEAD AND UPSTREAM WILL KEEP SKIES GENERALLY CLEAR. A
WEAK COOL FRONT WILL DIP SOUTHWARD INTO NRN AND NE NC TODAY...
FORCING CURRENT VERY LIGHT WIND MAINLY FROM THE SW TO BECOME
NORTHWESTERLY AT 8-12 KTS SUSTAINED AREAWIDE. SURFACE WINDS MAY GUST
AS HIGH AS 15-22 KTS ESPECIALLY AT RDU/RWI STARTING MID MORNING AND
CONTINUING UNTIL MID AFTERNOON... WHEN GUSTS WILL GRADUALLY
DECREASE. SURFACE WINDS WILL DIMINISH BY 23Z.

LOOKING BEYOND 06Z EARLY MON MORNING... VFR CONDITIONS WILL DOMINATE
THROUGH WED MORNING AS HIGH PRESSURE MOVES OFF THE SOUTHEAST
COAST... ALTHOUGH A PERIOD OF SUB-VFR FOG IS POSSIBLE EARLY TUE
MORNING AND AGAIN EARLY WED MORNING. AN APPROACHING COLD FRONT WILL
BRING A CHANCE OF MVFR CIGS/VSBYS WITH SHOWERS/STORMS WED AFTERNOON
THROUGH WED NIGHT. VFR CONDITIONS SHOULD RETURN THU AS HIGH PRESSURE
PASSES BY TO OUR NW. -GIH

&&

.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$

SYNOPSIS...HARTFIELD
NEAR TERM...WSS/VINCENT
SHORT TERM...PWB
LONG TERM...PWB
AVIATION...HARTFIELD

NWS RAH Office Area Forecast Discussion