Special Weather Statement, NWS Raleigh, NC

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RALEIGH NC
820 PM EST FRI JAN 10 2014

.SYNOPSIS...A STRONG COLD FRONT SWEEPS ACROSS THE REGION SATURDAY.
HIGH PRESSURE BUILDS BACK IN ON SUNDAY.

&&

.NEAR TERM /TONIGHT THROUGH SATURDAY NIGHT/...
AS OF 320 PM FRIDAY...

PATCHES OF LIGHT TO BRIEFLY MODERATE RAIN CONTINUE TO TRACK
NORTHWARD ACROSS CENTRAL NC IN THE WARM MOIST SLY FLOW A FEW
THOUSAND FEET ABOVE THE SURFACE. OBSERVED RAINFALL AMOUNTS HAVE
AVERAGE A FEW HUNDREDTHS PER HOUR EXPECT WHERE THE HEAVIER PATCHES
OF RAIN HAVE OCCURRED (>40DBZ) WHERE RAINFALL AMOUNTS AVERAGE CLOSE
TO A QUARTER OF AN INCH PER HOUR.

SATELLITE TRENDS INDICATE AN AREA OF EXPANDING/COOLING CLOUD TOPS
OVER SC...EXPANDING/HEADING INTO SOUTHERN SECTIONS OF NC AT 19Z IN
VICINITY OF A MODEST VORTICITY MAXIMUM LIFTING NE OVER THE REGION.
UNDERNEATH THESE EXPANDING/COOLING CLOUD TOPS...EXPECT AN AREA OF
MODERATE TO BRIEFLY HEAVY RAIN TO OCCUR. THIS AREA OF RAIN EXPECTED
TO LIFT NORTH-NE ACROSS THE PIEDMONT OF CENTRAL NC...LIKELY
AFFECTING THE AFTERNOON COMMUTE ALONG THE I-40/85 CORRIDOR FROM THE
TRIAD TO THE TRIANGLE.

WIDE VARIANCE IN TEMPS OBSERVED ACROSS THE REGION THIS AFTERNOON AS
TEMPS HAVE HELD IN THE 30S IN THE NW PIEDMONT WHERE A HYBRID CAD HAS
SET-UP. FARTHER SE...TEMPS HAVE WARMED INTO THE LOW-MID 60S OVER THE
SOUTHERN COASTAL PLAIN. AN INVERTED SFC TROUGH/CAD BOUNDARY
SEPARATES THESE TWO DISTINCT AIRMASS AND THIS FEATURE EXPECTED TO
LINGER INTO THE EVENING IN VICINITY OF I-95...THEN LIFT NORTH-
NORTHWEST AS A WARM FRONT LATER TONIGHT.

AS BOUNDARY LIFTS NWD...RAIN SHOWERS WILL BECOME LESS NUMEROUS WITH
JUST SCATTERED SHOWERS EXPECTED ACROSS THE REGION OVERNIGHT.
ALSO...SLY WINDS WILL BEGIN TO INCREASE...ESPECIALLY AFTER
MIDNIGHT...AS A DEEP MID-UPPER LEVEL TROUGH AND ATTENDANT SFC COLD
FRONT ADVANCES TOWARD THE CAROLINAS. THIS UPTICK IN THE SLY WINDS
WILL CAUSE TEMPS TO RISE OVERNIGHT. FOR MANY FOLKS...THE MAX TEMP
FOR JANUARY 10TH WILL OCCUR CLOSE TO MIDNIGHT. TEMPS BEFORE DAYBREAK
SHOULD RANGE FROM THE UPPER 40S TO NEAR 50 IN THE NW TO AROUND 60 IN
THE SANDHILLS AND COASTAL PLAIN.

SATURDAY...ACTIVE WEATHER DAY POSSIBLY IN STORE AS STRONG LOW LEVEL
JET (50-60KTS) OCCURRING AHEAD OF THE MID-UPPER LEVEL TROUGH WILL
CONTINUE TO TRANSPORT WARM MOIST AIR INTO CENTRAL NC. PRECIPITABLE
WATER VALUES BY SATURDAY MORNING SHOULD BE 1.5-1.6 INCHES...WELL
ABOVE NORMAL FOR THIS TIME OF YEAR. THE MID-UPPER LEVEL TROUGH WILL
ACTUALLY STRENGTHEN AS IT GETS CLOSER TO OUR REGION AND TAKE ON A
NEUTRAL TO SLIGHTLY NEGATIVE TILT BY 00Z SUNDAY. THIS WILL ALLOW
SLIGHTLY COOLER AIR TO OVERSPREAD THE CAROLINAS ALOFT...RESULTING IN
MID LEVEL LAPSE RATES AROUND 6 DEG C/KM. UPPER DIVERGENCE WILL ALSO
INCREASE OVER OUR FORECAST AREA AS UPPER JET EXTENDING ALONG/JUST
WEST OF THE APPALACHIANS INCREASES TO AROUND 140KTS.

MANY PARAMETERS IN PLACE TO SUPPORT WIDESPREAD SHOWERS WITH HEAVY
RAIN POSSIBLE. STILL SOME QUESTION AS TO THE AMOUNT OF SFC BASED
INSTABILITY. LATEST MODEL RUN SIMILAR OR SLIGHTLY BETTER WITH
AVAILABLE INSTABILITY. NAM-GFS SUGGEST MLCAPE 400-700 J/KG DURING
THE AFTERNOON. WHILE THE INSTABILITY OUTSTANDING...THE STRONG
KINEMATICS (BULK SHEAR 50-60KTS AND 0-1KM SHEAR HELICITY 200-300
M2/S2) WILL MORE THAN MAKE UP FOR THIS. SOUNDING HODOGRAPHS DEPICT
LONG CURVED PROFILES INDICATIVE OF CONVECTIVE LINES WITH POSSIBLE
SUPERCELLS. CONSIDERING THE STRENGTH OF THE WINDS IN THE LOWEST 10K
FEET...EXPECT STRONG WIND GUSTS WITH ANY BANDS OF CONVECTION THAT
DEVELOP WITH ISOLATED DAMAGING WIND GUSTS POSSIBLE. COULD SEE A FEW
ROTATING STORMS...ONE OR TWO EMBEDDED IN THE CONVECTIVE LINE ALONG
OF THE FRONT...AND A FEW STORMS WELL AHEAD OF THE LINE. THIS SUGGEST
A SLIGHT RISK FOR BRIEF TORNADOES SATURDAY AFTERNOON...MAINLY ALONG
AND EAST OF HIGHWAY 1.

TEMPS SATURDAY AFTERNOON AHEAD OF THE CONVECTIVE LINE SHOULD BE WELL
INTO THE 60S TO AROUND 70 IN THE WEST TO THE LOWER (POSSIBLY MID
70S) IN THE EAST.

SATURDAY NIGHT...COLD FRONT SHOULD EXIT OUR COASTAL PLAIN COUNTIES
PRIOR TO 10 PM. BACK EDGE OF SHOWERS SHOULD BE ALONG THE HIGHWAY 1
CORRIDOR AROUND 7 PM...AND DIMINISH OVER THE COASTAL PLAIN BEFORE
MIDNIGHT. STRONG SUBSIDENCE IN THE WAKE OF THE TROUGH ALONG WITH
MUCH DRIER AIR ADVECTING INTO THE REGION ON WLY WINDS WILL CAUSE
SKIES TO CLEAR WEST-TO-EAST DURING THE EVENING AND INTO THE
OVERNIGHT HOURS. MIN TEMPS WILL RANGE FROM NEAR 40 NW TO MID 40S SE.

&&

.SHORT TERM /SUNDAY THROUGH MONDAY/...
AS OF 120 PM FRIDAY...

A BRIEF QUIET PERIOD. THE MID LEVEL TROUGH AXIS IS EXPECTED TO BE
SITUATED OVER THE EAST COAST SUNDAY MORNING... WITH HIGH PRESSURE
OVER THE CENTRAL GULF COAST STATES. WHILE THERE MAY BE A LITTLE
MORNING CLOUDINESS IN NC AS THE LAST BATCH OF ENERGY DROPS INTO THE
TROUGH BASE SWINGING IT QUICKLY OFFSHORE... FORECAST SOUNDINGS
DEPICT LOW LEVEL DOWNSLOPE FLOW AND DEEP DRYING TAKING PLACE PRIOR
TO DAYBREAK AND STRONG MID LEVEL WARMING THROUGHOUT THE DAY AS THE
RIDGE ALOFT SHIFTS OVER THE SOUTHEAST STATES WITHIN A VERY
PROGRESSIVE PATTERN. SHALLOW MIXING SHOULD MAKE FOR SLIGHTLY COOLER
TEMPS THAN THICKNESSES WOULD IMPLY... AND EXPECT HIGHS SUNDAY OF 54-
60. LOWS SUN NIGHT 34-39 UNDER CLEAR SKIES WITH LIGHT WINDS AND GOOD
RADIATIONAL COOLING. THE SURFACE HIGH MOVES QUICKLY ENE OFF THE
SOUTHEAST COAST EARLY MONDAY... AS ANOTHER LONGWAVE TROUGH DIGS TO
OUR WEST OVER TX/OK/AR/LA BY LATE MONDAY. STRENGTHENING MID-UPPER
LEVEL WINDS FROM THE SW AHEAD OF THIS TROUGH SHOULD BRING A
THICKENING VEIL OF HIGH CLOUDS FROM THE WSW DURING MONDAY. RISING
THICKNESSES TO WELL ABOVE NORMAL VALUES SUPPORT HIGHS OF 57-65. -GIH

&&

.LONG TERM /MONDAY NIGHT THROUGH THURSDAY/...
AS OF 300 PM FRIDAY...

FOR MONDAY NIGHT THROUGH WEDNESDAY: THE GFS/ECMWF CONTINUE TO SHOW A
LONGWAVE TROUGH CROSSING CENTRAL/ERN NORTH AMERICA DURING THIS
PERIOD... ALTHOUGH DIFFERENCES REGARDING TIMING AND PHASING PERSIST.
THE SOUTHERN PORTION OF THIS TROUGH APPROACHES FROM THE WEST MON
NIGHT... AND WHILE THE ECMWF HAS SPED UP IN RECENT RUNS TO BE CLOSER
TO THE GFS SOLUTION... IT REMAINS NOTABLY STRONGER AND MORE
AMPLIFIED THAN THE GFS. THIS MEANS THAT THE ECMWF IS MUCH WETTER FOR
CENTRAL NC (ESPECIALLY LATE MON NIGHT THROUGH TUE) WITH THE WARM
SECTOR SURGING WELL INLAND (SIMILAR TO SATURDAY'S EVENT) LEADING TO
GUSTY SW WIND AND POSSIBLE A STORM OR TWO... WHILE THE GFS IS MUCH
FASTER/LESS AMPLIFIED WITH WEAKER SHEARED VORTICITY CROSSING THE
AREA ABOUT 6 HRS EARLIER AND JUST A QUICK SHOT AT VERY LIGHT PRECIP
LATE MON NIGHT-TUE. THERE IS NO CLEAR WINNER HERE... ALTHOUGH THE
ECMWF DOES HAVE A BIT OF A DEEP/SLOW BIAS ACCORDING TO WPC... SO
WILL NOT GO ENTIRELY INTO ANY ONE SOLUTION... BUT MAINTAIN GOOD
CHANCE POPS MON NIGHT THROUGH TUE AFTERNOON... ENDING BY EVENING AS
THE SOUTHERN PORTION OF THE TROUGH STARTS LIFTING TO THE NE IN
RESPONSE TO NORTHERN STREAM ENERGY DIGGING BACK OVER THE MIDWEST AND
MID/LOWER MISS VALLEY. EXPECT TEMPS TUE THAT ARE SLIGHTLY COOLER
THAN NORMAL IN THE NW AND WARMER THAN NORMAL IN THE SE... TO ACCOUNT
FOR A POSSIBLE INLAND-MOVING WARM SECTOR. A WNW LOW LEVEL FLOW
FOLLOWS FOR TUE NIGHT/WED AS NORTHERN STREAM VORTICITY DIVES INTO
THE MIDSOUTH AND NRN GULF STATES BEFORE SWINGING ENE INTO THE WRN
CAROLINAS. WITH THIS FEATURE THE GFS IS FASTER AND STRONGER WITH
THIS ENERGY COMPARED TO THE ECMWF BUT IS STILL LESS AMPLIFIED... AND
AS A RESULT THE ECMWF HAS LESS OF A DRYING DOWNSLOPE LOW LEVEL WIND
COMPONENT... A LITTLE MORE MOISTURE INFLUX OPPORTUNITY... AND
GREATER HEIGHT FALLS... AND HENCE IT GENERATES MORE PRECIP
ESPECIALLY OVER NRN/WRN NC THAN THE GFS. BASED ON PARTIAL
THICKNESSES AND FORECAST SOUNDINGS FROM BOTH MODELS... ANY PRECIP
WOULD LIKELY BE IN THE FORM OF CONVECTIVE SNOWSHOWERS... LIKELY
MIXED WITH RAIN SHOWERS WHERE THE SHALLOW SURFACE-BASED ABOVE-
FREEZING LAYER IS SUFFICIENTLY DEEP EAST OF HIGHWAY 1. REGARDLESS...
WILL KEEP TEMPS ON THE LOW SIDE WED AS WE ARE LIKELY TO SEE A CHILLY
AIR MASS IN PLACE WITH PLENTY OF CLOUDS.

FOR THURSDAY/FRIDAY... WEDNESDAY'S DEEP TROUGH AXIS SHIFTS OFF THE
EAST COAST THU MORNING... WITH HIGH PRESSURE CROSSING THE NRN GULF
AND SOUTHERN GULF COAST AND SOUTHEAST STATES. EXPECT ANOTHER VERY
BRIEF RESPITE IN THE ACTIVE WEATHER... GIVEN THIS VERY PROGRESSIVE
PATTERN WE'RE IN... AS WE WILL SEE YET ANOTHER BROAD AND FAIRLY DEEP
TROUGH DIGGING OVER NORTHEAST NORTH AMERICA BY FRIDAY. EXPECT ABOVE-
NORMAL TEMPS THU AFTERNOON THROUGH FRI AS WE GET RETURN W AND WSW
FLOW WITH THE DEPARTING HIGH... AND DRY WEATHER SHOULD PERSIST AS WE
LACK ANY FEED OF MOISTURE INTO THE AREA. -GIH

&&

.AVIATION /00Z SATURDAY THROUGH WEDNESDAY/...
AS OF 740 PM FRIDAY...

ADVERSE AVIATION CONDITIONS ARE EXPECTED TO CONTINUE FOR THE 24 HOUR
TAF PERIOD.

LIFR CONDITIONS THIS EVENING AT KGSO/KINT/KRDU ARE EXPECTED TO
SPREAD EAST/SOUTHEASTWARD TO KFAY/KRWI LATER THIS EVENING INTO EARLY
SATURDAY MORNING AS THE MAIN AREA OF RAIN BEGINS TO LIFT NORTH AND
EAST OF THE AREA... LEAVING CENTRAL NC IN A MOIST AIRMASS WITH
PATCHY RAIN AND DRIZZLE POSSIBLE. THIS WILL YIELD LOW CIGS AND
VISBYS (WITH POSSIBLY SOME DENSE FOG AFTER MIDNIGHT)... ESPECIALLY
IN THE HEART OF THE DAMMING REGION AT KGSO/KINT... WHERE LIFR
CONDITIONS MAY PERSIST INTO LATE SATURDAY MORNING... MAYBE EVEN
EARLY SATURDAY AFTERNOON.  THUS... EXPECT WE MAY SEE SOME
IMPROVEMENT IN THE CIGS AND VISBYS BY AROUND 10-12Z AT KFAY AND
KRWI... WHERE THE CAD AIRMASS IS EXPECTED TO RETREAT FIRST... THEN
SPREAD WESTWARD THROUGH THE DAY. WE STILL MAY HOLD ONTO MVFR
CONDITIONS THOUGH BEFORE THE NEXT ROUND OF SHOWERS AND POSSIBLE SOME
STORMS CROSSES THE AREA SATURDAY AFTERNOON ALONG AND IN ADVANCE OF A
COLD FRONT. BEHIND THE FRONT EXPECT WE WILL SEE SUB-VFR CONDITIONS
SCATTER ALONG WITH A RETURN TO DRY WEATHER. THE SURFACE FRONT SHOULD
MOVE THROUGH KGSO/KINT/KRDU SATURDAY AFTERNOON... AND BE INVOF KRWI
AND KFAY NEAR THE END OF THE TAF PERIOD.

IN ADDITIONS TO THE SUB-VFR CIGS AND VISBYS... WE WILL LIKELY SEE
SOME LLWS CONDITIONS AT KGSO/KINT/KRDU AND POSSIBLY KRWI AND KFAY...
AS SOUTHERLY WINDS AT AROUND 30-40 KTS (AT AROUND ONE THOUSAND FEET)
ARE EXPECTED ABOVE COOL STABLE LAYER AT THE SURFACE... WHERE WINDS
ARE EXPECTED TO BE NORTHEASTERLY TO LIGHT AND VARIABLE. HOWEVER...
AS THE CAD RETREATS AND THE WARM AIR BEGINS TO SURGE INLAND WE WILL
BEGIN TO MIX DOWN SOME OF THESE STRONGER SOUTH TO SOUTHWESTERLY
WINDS... YIELDING WINDS OF 15 TO 20 MPH... WITH GUSTS OF UP TO 30
MPH POSSIBLE.

OUTLOOK: VFR CONDITIONS ARE EXPECTED LATE SAT NIGHT THROUGH WED BUT
WITH TWO EXCEPTIONS: ANOTHER STORM SYSTEM WILL BRING A CHANCE FOR
IFR CONDITIONS LATE MON NIGHT THROUGH MID MORNING TUE WITH A LITTLE
LIGHT RAIN POSSIBLE.... THEN A FAST-MOVING UPPER DISTURBANCE MAY
BRING A PERIOD OF SUB-VFR CIGS WED AFTERNOON.

&&

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

&&

SYNOPSIS...DJF
NEAR TERM...WSS
SHORT TERM...HARTFIELD
LONG TERM...HARTFIELD
AVIATION...BSD/HARTFIELD

HAZARDOUS WEATHER OUTLOOK...UPDATED
NATIONAL WEATHER SERVICE RALEIGH NC
337 PM EST FRI JAN 10 2014

NCZ021>023-038-039-073>075-083-084-111030-
FORSYTH-GUILFORD-ALAMANCE-DAVIDSON-RANDOLPH-STANLY-MONTGOMERY-MOORE-
ANSON-RICHMOND-
337 PM EST FRI JAN 10 2014

THIS HAZARDOUS WEATHER OUTLOOK IS FOR CENTRAL NORTH CAROLINA.

.DAY ONE...THIS AFTERNOON AND TONIGHT.

HAZARDOUS WEATHER IS NOT EXPECTED AT THIS TIME.

.DAYS TWO THROUGH SEVEN...SATURDAY THROUGH THURSDAY.

SHOWERS...POSSIBLY A FEW THUNDERSTORMS...WITH VERY GUSTY WINDS
COULD OCCUR SATURDAY. WIND GUSTS COULD REACH 40 TO 50 MPH. EVEN
OUTSIDE OF ANY STRONGER SHOWER OR STORM...WIND GUSTS COULD REACH
30 TO 35 MPH. THE THREAT FOR STRONG WIND GUSTS WITH THE SHOWERS
AND STORMS WILL BE HIGHEST BETWEEN NOON AND 6 PM.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION MAY BE NEEDED BETWEEN NOON AND 6 PM SATURDAY.

NCZ007>011-024>028-040>043-076>078-085-086-088-089-111030-
PERSON-GRANVILLE-VANCE-WARREN-HALIFAX-ORANGE-DURHAM-FRANKLIN-NASH-
EDGECOMBE-CHATHAM-WAKE-JOHNSTON-WILSON-LEE-HARNETT-WAYNE-SCOTLAND-
HOKE-CUMBERLAND-SAMPSON-
337 PM EST FRI JAN 10 2014

THIS HAZARDOUS WEATHER OUTLOOK IS FOR CENTRAL NORTH CAROLINA.

.DAY ONE...THIS AFTERNOON AND TONIGHT.

HAZARDOUS WEATHER IS NOT EXPECTED AT THIS TIME.

.DAYS TWO THROUGH SEVEN...SATURDAY THROUGH THURSDAY.

SHOWERS AND SCATTERED THUNDERSTORMS COULD PRODUCE STRONG TO SEVERE
WIND GUSTS SATURDAY AFTERNOON THROUGH EARLY SATURDAY EVENING. THE
MAIN THREAT WILL BE DAMAGING WIND GUSTS WITH A SLIGHT RISK FOR
BRIEF WEAK TORNADOES. EVEN OUTSIDE OF ANY STRONGER SHOWER OR
STORM...WIND GUSTS COULD REACH 30 TO 35 MPH. THE SEVERE WEATHER
THREAT APPEARS GREATEST BETWEEN 2 PM AND 8 PM.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION MAY BE NEEDED SATURDAY BETWEEN NOON AND 8 PM.

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE RALEIGH NC
901 PM EST FRI JAN 10 2014

NCZ042-077-088-089-110245-
HARNETT-SAMPSON-CUMBERLAND-JOHNSTON-
901 PM EST FRI JAN 10 2014

...SHOWERS WITH GUSTY WINDS WILL MOVE ACROSS EASTERN
HARNETT...NORTHWESTERN SAMPSON...CUMBERLAND AND SOUTHWESTERN
JOHNSTON UNTIL 945 PM EST...

AT 858 PM EST...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
SHOWER 8 MILES SOUTH OF GODWIN...OR 13 MILES EAST OF FAYETTEVILLE...
MOVING NORTHEAST AT 35 MPH.

WIND GUSTS UP TO 40 MPH WILL BE POSSIBLE WITH THESE SHOWERS.

LOCATIONS IMPACTED INCLUDE...
FAYETTEVILLE...LILLINGTON...DUNN...ANGIER...BENSON...GODWIN...SPIVEYS

CORNER...BUIES CREEK...ERWIN... EASTOVER...COATS...STEDMAN...NEWTON
GROVE...WADE...FALCON...LINDEN AND SPIVEY'S CORNER.

LAT...LON 3509 7894 3552 7872 3535 7819 3534 7820
      3534 7821 3532 7824 3533 7826 3531 7829
      3529 7831 3527 7828 3495 7864
TIME...MOT...LOC 0158Z 208DEG 31KT 3510 7866

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