-- Discussion containing changed information from previous version are highlighted. --
000
FXUS62 KRAH 261951
AFDRAH

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RALEIGH NC
251 PM EST THU FEB 26 2015

.SYNOPSIS...
LOW PRESSURE WILL MOVE AWAY FROM THE NORTH CAROLINA
COAST THIS MORNING. COLD CANADIAN HIGH PRESSURE WILL FOLLOW THE
STORM FRIDAY INTO SATURDAY.

&&

.NEAR TERM /THROUGH FRIDAY/...
AS OF 1025 AM THURSDAY...

     ACCUMULATING PRECIPITATION HAS ENDED BUT THREAT OF FALLING LIMBS
AND TREES CONTINUES FROM HEAVY WET SNOW AND A WINTRY MIX...

WE WILL CONTINUE THE WINTER STORM WARNING FOR A LARGE PART OF
CENTRAL NC EARLY THIS MORNING TO COVER THE THREAT FROM FALLING TREES
AND BRANCHES AS WELL AS DIFFICULT TRAVEL CONDITIONS MAINLY FROM
ASHEBORO...RALEIGH AND ROCKY MOUNT NORTH. THE WARNING WILL BE
ALLOWED TO EXPIRE AT NOON. WE WILL CANCEL THE WINTER ADVISORY FOR
OUR FAR SOUTHERN TIER AS TEMPERATURES HAVE WARMED INTO THE MID 30S.

EXPECT ONLY SOME AREAS OF LINGERING DRIZZLE AND FREEZING DRIZZLE FOR
THE NEXT FEW HOURS ACROSS THE EASTERN PIEDMONT AND COASTAL PLAIN
WITH DRY WEATHER BUT A LOW OVERCAST FOR MOST OF THE AFTERNOON.
TEMPERATURES WILL CLIMB A FEW DEGREES INTO THE MID TO UPPER 30S BY
LATE AFTERNOON.

FORECAST FOR TONIGHT IS COMPLICATED BY THE DEGREE OF CLEARING WHICH
WILL HAVE A BIG IMPACT ON LOW TEMPERATURES. IF SKIES CLEAR...LOW
TEMPERATURES TONIGHT COULD FALL A CATEGORY OR TWO BELOW THE CURRENT
FORECAST OF THE LOWER TO MID 20S. WILL EVALUATE THIS ISSUE FOR THIS
AFTERNOONS PACKAGE. REGARDLESS OF HOW COLD IT GETS... MOISTURE...
SLUSH AN SNOW WILL LIKELY RE-FREEZE LATE TONIGHT LEADING TO
WIDESPREAD BLACK ICE CONDITIONS. FOR THE AFTERNOON PACKAGE WE PLAN
ON ISSUING A WINTER WEATHER ADVISORY FOR BLACK ICE FOR LATE TONIGHT-
EARLY FRI MORNING.


FRIDAY AND FRIDAY NIGHT: ANOTHER WEAK S/W DISTURBANCE IS EXPECTED TO
MOVE ACROSS THE REGION IN THE WEST-SOUTHWESTERLY MID LEVEL FLOW.
HOWEVER... WITH PW`S LESS THAN THREE TENTHS OF AN INCH OR SO EXPECT
WE WILL SEE LITTLE IF ANY PRECIP. WILL KEEP MENTION OF FLURRIES IN
THE FORECAST FOR LATE FRIDAY AFTERNOON INTO THE EVENING ACROSS THE
PIEDMONT... AS THE LATEST GFS BUFR SOUNDINGS CONTINUE TO SHOW SOME
SATURATION UP CLOSE TO -10C ACROSS WESTERN AND NORTHERN PORTIONS OF
CENTRAL NC... WITH STEEP LOW LEVEL LAPSE RATES. CANT RULE OUT A VERY
BRIEF LIGHT SNOW SHOWER OR TWO, BUT FEEL NOTHING WILL BE MEASURABLE.
EXPECT HIGH TEMPS FRIDAY WILL BE IN THE MID TO UPPER 30S NORTH TO
NEAR 40 SOUTH.

SURFACE HIGH PRESSURE OVER THE MID MS RIVER VALLEY AND OHIO VALLEY
ON FRIDAY EVENING WILL BUILD EAST AND SOUTHWARD OVERNIGHT INTO
CENTRAL NC. THIS YIELD LOW TEMPS BY SATURDAY MORNING IN THE TEENS TO
LOWER 20S ACROSS THE AREA.

&&

.SHORT TERM /FRIDAY NIGHT THROUGH SATURDAY/...
AS OF 325 AM THURSDAY...


SATURDAY: SURFACE HIGH PRESSURE WILL EXTEND INTO OUR REGION FROM THE
NORTH ON SATURDAY... WITH POSSIBLY SOME HIGH CLOUDS INCREASING LATE
IN THE DAY IN THE WEST TO WEST-SOUTHWESTERLY MID LEVEL FLOW IN
ADVANCE OF THE NEXT SYSTEM. THIS WILL YIELD HIGH TEMPS AGAIN WELL
BELOW NORMAL... WITH AFTERNOON LOW LEVEL THICKNESS VALUES SOME 50+
METERS BELOW NORMAL. EXPECT HIGH TEMPS TO BE IN THE 30S.

&&

.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
AS OF 1200 PM WEDNESDAY...

THE LONG-TERM SATURDAY NIGHT THROUGH WEDNESDAY IS CATEGORIZED BY
SOME UNCERTAINTY IN PRECIPITATION TIMING AND TYPE...WITH AT LEAST
MODEST CONFIDENCE IN MUCH WARMER TEMPERATURES DEVELOPING BY THE END
OF THIS PERIOD THAN WHAT HAS BEEN OCCURRING RECENTLY. DRYING IS
FORECAST FOR SATURDAY NIGHT...WITH A MID-LEVEL SHORTWAVE MOVING INTO
THE CAROLINAS BY SUNDAY NIGHT. AS HEIGHTS ALOFT RISE LATE IN THE
WEEKEND AND EARLY NEXT WEEK...THE 06Z GFS IN PARTICULAR AND POSSIBLY
EVEN THE 12Z GFS SEEMS TO HAVE ISSUES WITH FEEDBACK SUCH THAT THE
ECMWF IS PREFERRED OVERALL. IT SHOULD BE COLD TO START SUNDAY
MORNING AS CLOUDS INCREASE...BUT THE GFS AND ECMWF TREND OF A LATER
ARRIVAL OF MID-LEVEL VORTICITY AND OVERALL MOISTURE INCREASE SHOULD
RESULT IN PRECIPITATION BEING IN THE FORM OF LIQUID BY THE TIME ANY
WOULD ARRIVE LATER IN THE DAY. PARTIAL THICKNESSES AND MODEL
SOUNDINGS CURRENTLY SUPPORT THIS...AND WILL HAVE A CHANCE OF
AFTERNOON RAIN SUNDAY PRIMARILY TOWARD THE YADKIN RIVER FOLLOWED BY
CHANCES OF RAIN OVERNIGHT...WITH SURFACE TEMPERATURES REMAINING
ABOVE FREEZING AND MODEL SOUNDINGS SHOWING WARMING ALOFT AS 1000-
850MB THICKNESSES RISE AROUND 20M DURING THE NIGHT...SUGGESTING THE
POTENTIAL FOR LOW TEMPERATURES EARLY SUNDAY NIGHT FOLLOWED BY STEADY
OR A SLOW RISE IN READINGS LATE.

A BRIEF WARMUP OCCURS MONDAY AHEAD OF A COLD FRONT THAT MOVES
THROUGH CENTRAL NORTH CAROLINA LATER IN THE DAY AND AT NIGHT. STRONG
HIGH PRESSURE BUILDS IN BEHIND THE COLD FRONT...AND THE PATTERN
WOULD SUGGEST PRETTY CHILLY TEMPERATURES ONCE AGAIN WITH THE 1000-
850MB THICKNESSES SUGGESTING LOWS A LITTLE BELOW FREEZING. MOS
GUIDANCE LOWS ARE AT LEAST ONE IF NOT MORE CATEGORIES ABOVE THIS...
SO FOR NOW WILL SIMPLY UNDERCUT GUIDANCE WITH OVERNIGHT LOWS AT OR
SLIGHTLY ABOVE FREEZING. CONDITIONS SHOULD DRY BRIEFLY BEHIND THE
FRONT AS HIGH PRESSURE BUILDS IN...THEN UNCERTAINTY INCREASES AS THE
GFS AND THE ECMWF SUGGEST MOISTURE RETURNING TO CENTRAL NORTH
CAROLINA AS THE GULF OPENS BY TUESDAY INTO TUESDAY NIGHT. IF
PRECIPITATION WOULD RETURN TO CENTRAL NORTH CAROLINA QUICKLY ENOUGH
ON TUESDAY...PRECIPITATION TYPE CONCERNS WOULD EXIST DUE TO CHILLY
THICKNESSES TO START THE DAY. BY 00Z WEDNESDAY ON THE 12Z GFS...AND
FOR THE MOST PART ON THE 00Z ECMWF...THICKNESSES ARE WARM ENOUGH FOR
RAIN AND BASED ON THE WARM-AIR ADVECTION AT THE TIME WOULD
ANTICIPATE ANOTHER POTENTIAL NON-DIURNAL TEMPERATURE SCENARIO AS ANY
COLD-AIR DAMMING ERODES. BASED ON THE PATTERN WILL ONLY NOTE A
SLIGHT CHANCE OF RAIN OR SNOW EARLY ON THE SIXTH DAY IN THE WESTERN
PIEDMONT WITH A CHANCE OF JUST ALL RAIN THROUGHOUT CENTRAL NORTH
CAROLINA BY TUESDAY AFTERNOON. 1000-850MB THICKNESSES ON THE 12Z GFS
AND 00Z ECMWF ARE QUITE WARM WEDNESDAY...APPROACHING 1380M ON THE
LATEST GFS AND ONLY SLIGHTLY COOLER ON THE 00Z ECMWF...SUCH THAT...
WITH SHOWERY CONDITIONS IN A MOIST AIR MASS AND A SOUTHWEST FLOW
ALOFT...HIGH TEMPERATURES COULD POSSIBLY REACH THE 60S THROUGHOUT
CENTRAL NORTH CAROLINA WITH SOME TEMPERATURES PUSHING 70F ESPECIALLY
OVER PARTS OF THE SANDHILLS AND SOUTHERN COASTAL PLAIN.

&&

.AVIATION /18Z THURSDAY THROUGH TUESDAY/...
AS OF 250 PM THURSDAY...

ADVERSE AVIATION CONDITIONS ARE EXPECTED THROUGH MUCH OF THE TAF
FORECAST PERIOD. WIDESPREAD MVFR CEILINGS ACROSS CENTRAL NC WITH
BKN-OVC BASES AROUND 1.5-2.0KFT ARE EXPECTED TO CONTINUE THIS
AFTERNOON AND EARLY EVENING AS A RESIDUAL MOISTURE AIR MASS
REMAINS IN PLACE. AREAS OF FOG AND LOW STRATUS ARE EXPECTED TO
DEVELOP THIS EVENING WITH THE DEGREE OF THE VISIBILITY RESTRICTION
AND CEILINGS STILL SOMEWHAT UNCERTAIN. CONDITIONS AT THE SURFACE
ARE RATHER MOIST WITH A FRESH SNOW COVER OF WET SNOW AND MELT
WATER OR DAMP CONDITIONS FROM HEAVY RAIN LAST NIGHT. SKIES ARE NOT
EXPECTED TO CLEAR MUCH OVERNIGHT SO RADIATIONAL CONDITIONS ARE NOT
IDEAL AND THERE WILL BE WEAK COOL ADVECTION SO IT IS UNCLEAR HOW
POOR CONDITIONS WILL BECOME. BUT FOR FOR NOW WILL GO WITH A
FORECAST OF PREVAILING MVFR/IFR CIGS AND VSBYS TEMPORALLY FALLING
TO THE LIFR CIGS AND VSBYS LATE TONIGHT. CONDITIONS WILL GRADUALLY
IMPROVE WITH LINGERING FOG AN OVERCAST SKIES GIVING WAY TO SCT-BKN
CLOUDS WITH VFR BASES AROUND 3-3.5 KFT AROUND MIDDAY FRIDAY.

LOOKING FURTHER AHEAD...
GENERALLY FAIR WEATHER CONDITIONS ARE EXPECTED ON FRIDAY NIGHT
INTO SATURDAY NIGHT. AVIATION CONDITIONS ARE LIKELY TO DETEIORATE
ON SUNDAY WITH ADVERSE AVIATION CONDITIONS LIKELY PERSISTING INTO
MID WEEK. -BLAES

&&

.RAH WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY FROM 9 PM THIS EVENING TO 10 AM EST
FRIDAY FOR NCZ007>011-021>028-038>043-073>078-083>086-088-089.

&&

$$
SYNOPSIS...BLAES
NEAR TERM...BLAES
SHORT TERM...BSD
LONG TERM...DJF
AVIATION...BLAES