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-- Discussion containing changed information from previous version are highlighted. --
000
FXUS62 KRAH 091412
AFDRAH

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RALEIGH NC
1012 AM EDT SUN MAR 9 2014

.SYNOPSIS...
-- Changed Discussion --
A WEAK COLD FRONT WILL SETTLE SOUTH THROUGH CENTRAL NC
TODAY. BENEATH DRY WESTERLY FLOW ALOFT...A WEAK SURFACE TROUGH WILL
DEVELOP AND LINGER OVER THE CAROLINAS MONDAY AND TUESDAY.
-- End Changed Discussion --

&&

.NEAR TERM /THROUGH MONDAY NIGHT/...
-- Changed Discussion --
AS OF 1010 AM SUNDAY...

THROUGH TONIGHT: A POSITIVELY-TILTED SHORTWAVE TROUGH ALOFT ALONG
THE MIDDLE ATLANTIC COAST WILL RACE EASTWARD THIS MORNING BUT LEAVE
BEHIND A TRAILING MID LEVEL SHEAR AXIS THAT WILL ONLY SLOWLY SETTLE
SOUTH THROUGH THE CAROLINAS THROUGH TONIGHT. A PRECEDING BAND OF
ALTOCUMULUS AND VIRGA ROUGHLY ALONG HIGHWAY 64 THIS MORNING...WITH
MOSTLY CLOUDY/CEILINGS IN THE 8 TO 12 THOUSAND FT RANGE...WILL
SETTLE SOUTH THROUGH SOUTHERN NC THROUGH EARLY AFTERNOON. PERIODS OF
CIRRUS WILL OTHERWISE CONTINUE IN WEST TO WNW UPPER LEVEL FLOW...AS
THE SHEAR AXIS DRIFTS SOUTHWARD.

AT THE SURFACE...A WEAK COLD FRONT ATTENDING THE SHORTWAVE TROUGH
ALOFT WAS LOCATED NEAR THE VA BORDER AT 14Z...AND THE PASSAGE OF
THIS WEAK FEATURE TODAY WILL CAUSE INITIALLY LIGHT WESTERLY SURFACE
WINDS THIS MORNING TO VEER TO NORTHWESTERLY...STILL LIGHT GENERALLY
IN THE 6-12 KT RANGE...THIS AFTERNOON. A SLIGHTLY COOLER AIR
MASS...CHARACTERIZED BY PROJECTED AFTERNOON LOW LEVEL THICKNESS
VALUES 5-10 METERS LOWER THAN SATURDAY...SUPPORT HIGH TEMPS IN THE
63 TO TO 68 DEGREE RANGE - WARMEST OVER THE SOUTHERN PIEDMONT AND
SANDHILLS. PREVIOUSLY FORECAST LOWS IN THE MIDDLE 30S...TO AROUND 40
DEGREES OR SO SOUTH...LOOK GOOD.

MONDAY/MONDAY NIGHT...SURFACE HIGH CENTERED ACROSS THE DEEP
SOUTH/GULF OF MEXICO WILL RIDGE NORTHWARD INTO THE SOUTHEAST US.
THIS WILL KEEP OUR REGION DRY ON MONDAY. WITH CONTINUED WEAK
DOWNSLOPE FLOW AND SURFACE WINDS EXPECTED TO BE OUT OF THE SOUTHWEST
(COURTESY OF LEE SIDE TROUGH OVER THE AREA)...TEMPS SHOULD BE EVEN
WARMER ON MONDAY...GENERALLY IN THE LOW 70S AREAWIDE. MILDER
OVERNIGHT LOWS ARE ALSO EXPECTED...GENERALLY IN THE LOW TO MID 40S.
-- End Changed Discussion --

&&

.SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/...
AS OF 300 AM SUNDAY...

TUESDAY...WEAK LEE-SIDE TROUGHINESS WILL REMAIN OVER THE AREA ON
TUESDAY WITH CONTINUATION OF ZONAL FLOW ALOFT IN ADVANCE OF TWO
SEPARATE SHORTWAVES EMBEDDED IN THE SPLIT FLOW ALOFT. A LIGHT
SOUTHERLY WIND AND WESTERLY DOWNSLOPE WILL AIDE IN BOOSTING
TEMPERATURES A 2 TO 4 DEGREES WARMER THAN THE PREVIOUS DAY WITH
AFTERNOON HIGHS SOLIDLY IN THE 70S.

TUESDAY NIGHT THROUGH WEDNESDAY NIGHT...AN AMPLIFYING NORTHERN
STREAM TROUGH DROPPING SOUTH THROUGH THE NATIONS MID-SECTION WILL
ATTEMPT TO INTERCEPT GULF MOISTURE FROM A DAMPENING SOUTHERN STREAM
TROUGH EJECTING EAST-NORTHEASTWARD ACROSS THE NORTHERN GOM AND OFF
THE SE COAST ON WEDNESDAY.

CLOUDS WILL BE ON THE INCREASE LATE TUESDAY AFTERNOON/TUESDAY
EVENING WITH SHOWERS EXPECTED TO OVERSPREAD THE AREA FROM THE
WEST/SOUTHWEST LATE TUESDAY NIGHT AND INTO THE DAY ON WEDNESDAY
WITHIN THE CONSOLIDATED WARM CONVEYOR BELT ASCENT IN ADVANCE OF THE
NORTHERN STREAM TROUGH AND ATTENDANT SURFACE COLD FRONT. THE BIG
THREE(GFS/EC/CANADIAN)...ALL KEEP THE SURFACE WAVE NORTH OF THE
AREA...TRACKING IT THROUGH THE MID-ATLANTIC WEDNESDAY
AFTERNOON...WITH THE TRAILING SFC COLD FRONT CROSSING THE AREA BY
THE EARLY EVENING. THERE COULD BE A LULL MIDDAY WEDNESDAY BETWEEN
THE STRONG ISENTROPIC LIFT DURING THE MORNING AND THE ARRIVAL OF THE
STRONG DENSITY GRADIENT IN THE AFTERNOON/EARLY EVENING...BUT HAVE
PLENTY TIME TO GET CUTE WITH TIMING/POPS. FOR NOW WILL GO WITH A 12
HOUR BLOCK OF LIKELY POPS ON WEDNESDAY WITH AN INFLUX OF HIGH PWATS
OF 1.25-1.50" OVER THE AREA. INSTABILITY STILL APPEARS TO BE
LACKING...AS SUGGESTED BY THE MOIST ADIABATIC SOUNDING PROFILES AND
FORECAST OF BL DEWPOINTS ONLY IN THE 50S...SO THE PROBABILITY LOOKS
VERY LOW AT THIS TIME. HIGHS WEDNESDAY WILL DEPEND OF
TIMING/COVERAGE OF SHOWERS WITH THE CHANCE TO WARM UP A BIT IF THERE
IS INDEED A LULL DURING THE MIDDLE OF THE DAY. HIGHS IN THE LOWER
60S NORTH TO NEAR 70 SOUTH.

SHOWERS SHOULD EXIT THE AREA DURING THE EVENING WITH STRONG CAA
CLEARING OVERNIGHT. LOWS WEDNESDAY NIGHT IN THE 30S.

&&

.LONG TERM /THURSDAY THROUGH SATURDAY/...
AS OF 300 AM SUNDAY...

AN OLD TOO FAMILIAR PATTERN THAT WE HAVE SEEN MUCH THROUGHOUT THIS
WINTER OF AN UPPER RIDGING FORECAST TO HOLD STRONG OVER THE PAC NW
WITH DOWNSTREAM TROUGHING OVER THE EASTERN THIRD OF THE CONUS LOOKS
TO SET BACK UP TOWARDS THE LATTER HALF OF THE WORK WEEK AND INTO THE
WEEKEND. NEGATIVE H5 ANOMALIES ATTENDANT TO THE NORTHERN STREAM
TROUGH WILL SUPPORT BELOW NORMAL TEMPERATURES THURSDAY AND FRIDAY...
MODERATING TO NEAR NORMAL BY THE WEEKEND UNDER ZONAL FLOW ALOFT.

IT LOOKS LIKE IT WILL REMAIN DRY THROUGH A GOOD PART...IF NOT THE
ENTIRE WEEKEND...WITH THE NEXT CHANCE OF PRECIP/RAIN DEPENDENT ON
THE TIMING OF A NORTHERN STREAM TROUGH DIGGING SOUTHWARD THROUGH
ROCKIES...LIKELY INCITING ANOTHER SOUTHERN STREAM STORM SYSTEM IN
THE GULF.

&&

.AVIATION /14Z SUNDAY THROUGH THURSDAY/...
-- Changed Discussion --
AS OF 1000 AM SUNDAY...

VFR. A BAND OF ALTOCUMULUS AND VIRGA ROUGHLY ALONG HIGHWAY 64 THIS
MORNING...WITH CEILINGS IN THE 8 TO 12 THOUSAND FT RANGE...WILL
SETTLE SOUTH THROUGH SOUTHERN NC THROUGH EARLY AFTERNOON...AS THE
PARENT MID-UPPER DISTURBANCE PASSES OFF THE MIDDLE ATLANTIC COAST. A
WEAK COLD FRONT ATTENDING THE DISTURBANCE WAS LOCATED NEAR THE VA
BORDER AT 14Z...AND THE PASSAGE OF THIS WEAK FEATURE TODAY WILL
CAUSE INITIALLY LIGHT WESTERLY SURFACE WINDS THIS MORNING TO VEER TO
NORTHWESTERLY...STILL LIGHT GENERALLY IN THE 6-12 KT RANGE...THIS
AFTERNOON.

OUTLOOK: BREEZY SOUTHWEST WINDS...SHOWERS...AND MOSTLY MVFR CEILINGS
AND VISIBILITY RESTRICTIONS...WILL ACCOMPANY A PASSING LOW PRESSURE
SYSTEM LATE TUE NIGHT THROUGH WED.
-- End Changed Discussion --

&&

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

&&

$$

SYNOPSIS...MWS
NEAR TERM...MWS/KRD
SHORT TERM...CBL
LONG TERM...CBL
AVIATION...MWS