-- Discussion containing changed information from previous version are highlighted. --
000
FXUS62 KRAH 061852
AFDRAH

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RALEIGH NC
150 PM EST FRI MAR 6 2015

.SYNOPSIS...ARCTIC HIGH PRESSURE WILL BUILD INTO THE AREA TODAY AND
SETTLE OVER THE REGION TONIGHT AND SATURDAY. A SUBSTANTIAL WARMING
TREND WILL COMMENCE ON SUNDAY.

&&

.NEAR TERM /THROUGH TONIGHT/...
AS OF 910 AM FRIDAY...

CANCELED ADVISORY FOR BLACK ICE AS ONLY ISOLATED SPOTS OF BLACK ICE
BEING REPORTED. A NARROW BAND OF STRATOCU EDGING SLOWLY WEST ACROSS
THE WESTERN PIEDMONT AT MID MORNING PRODUCING A FEW LIGHT SNOW
FLURRIES AS OBSERVED AT GSO/PTI AIRPORT SHORTLY AFTER 13Z. THIS BAND
OF CLOUDINESS WILL GRADUALLY DISSOLVE AS IT CONTINUES TO DRIFT WEST-
SW. OTHERWISE...ASIDE FROM PATCHES OF HIGH CIRRUS ASSOCIATED WITH
THE UPPER LEVEL JET OVER OUR SE COUNTIES...EXPECT SUNNY-MOSTLY SUNNY
SKIES. LOW LEVEL CAA WILL LIMIT NORMAL DIURNAL TEMP RECOVERY TODAY.
TEMPS WILL STRUGGLE TO NEAR FREEZING OVER THE NORTH BY MID DAY/EARLY
AFTERNOON. CURRENT HIGH TEMPS FORECAST APPEARS ON TARGET...RANGING
FROM THE MID 30S NE TO THE LOWER 40S SW.

TONIGHT...HIGH PRESSURE SETTLING OVER THE AREA WILL PROVIDE CLEAR
SKIES AND CALM WINDS. THIS WILL ALLOW TEMPS TO PLUMMET INTO THE 20S
PRIOR TO MIDNIGHT. MIN TEMPS UPPER TEENS TO NEAR 20 NE AND LOW-MID
20S SOUTH AND WEST.


&&

.SHORT TERM /SATURDAY THROUGH SATURDAY NIGHT/...
AS OF 230 AM FRIDAY...

MODERATION IN A GRADUAL SENSE SATURDAY INTO SATURDAY NIGHT
UNDER HIGH PRESSURE AND MOSTLY CLEAR/SUNNY SKIES. TEMPS RETURN TO
CLOSER TO NORMAL.

&&


.LONG TERM /SUNDAY THROUGH FRIDAY/...
-- Changed Discussion --
AS OF 150 PM FRIDAY...

FOR SUN THROUGH MON: SURFACE HIGH PRESSURE WILL CONTINUE TO STRETCH
ACROSS NC SUN/SUN NIGHT... SPLIT BY A WEAK LEE TROUGH HOLDING OVER
OUR WESTERN SECTIONS. EXPECT A CONTINUED SLOW INCREASE IN HIGH
CLOUDS AS ENERGY EMANATING FROM THE DESERT SOUTHWEST LOW SPREADS ENE
TOWARD THE SRN APPALACHIANS... ESPECIALLY LATE SUNDAY THROUGH SUN
NIGHT. FORCING FOR ASCENT WILL BE BRIEFLY STRENGTHENED OVER OUR
NORTHWEST SUN NIGHT INTO MON MORNING BY PASSING UPPER DIVERGENCE...
IN THE RIGHT ENTRANCE REGION OF 140+ KT WESTERLY JET CROSSING THE
MIDATLANTIC REGION... AND THIS MAY GENERATE A FEW SHOWERS ACROSS OUR
NORTHWEST AND FAR NORTH IN THE LATE SUN NIGHT/MON TIME FRAME. BUT
FORECAST SOUNDINGS SHOW FAIRLY DRY AIR THROUGH THE LOWEST 6KFT OR
SO... SUGGESTING THAT THE CHANCE OF ANYTHING MEASURABLE WILL BE
PRETTY LOW... AND THIS IS MIRRORED BY VERY LOW SREF PRECIP
PROBABILITIES. WILL GO WITH NO MORE THAN A MENTION OF SPRINKLES. THE
GFS/ECMWF STRIVE TO SPREAD LIGHT PRECIP INTO THE FAR SRN CWA LATE
MON... BUT WITH FORECAST SOUNDINGS STILL SHOWING HIGH CLOUD BASES
AND A DRY SUBCLOUD LAYER AS THE ESE LOW LEVEL FLOW REMAINS ERRATIC
AND LIGHT... AND WITH MID LEVEL RIDGING CENTERED EAST OF THE BAHAMAS
BUILDING INTO THE CAROLINAS... WILL DELAY POPS UNTIL VERY LATE IN
THE DAY. THICKNESSES WILL BE TRENDING UPWARD... PEAKING AT SLIGHTLY
ABOVE NORMAL VALUES EACH DAY... BUT THE CLOUDINESS SHOULD TAKE THE
EDGE OFF MAXES AND TIGHTEN UP THE DIURNAL RANGE A BIT. HIGHS BOTH
SUN/MON IN THE UPPER 50S TO MID 60S. LOWS SUN NIGHT UPPER 30S TO
LOWER 40S.

FOR MON NIGHT THROUGH FRI: AN ACTIVE PERIOD WITH MORE CLOUDS THAN
SUNSHINE... AND OVERALL FAIRLY SEASONABLE TEMPS. MID LEVEL TROUGHING
WITH A SLIGHT POSITIVE TILT FROM THE CENTRAL PLAINS DOWN TO BAJA
WILL ATTEMPT TO  SHIFT EASTWARD NEXT WEEK. ENERGY DROPPING INTO ITS
BASE WILL DELAY ITS MOVEMENT... AS WILL THE STRONG MID LEVEL RIDGING
CENTERED NORTH OF PUERTO RICO AND EXTENDING INTO THE SOUTHEAST
STATES INTO MIDWEEK. BUT THE MID LEVEL FLOW OVER THE GULF AND
SOUTHEAST STATES WILL BACK FROM WESTERLY TO SOUTHWESTERLY... DRAWING
MOISTURE INTO OUR AREA ALONG WITH INCREASING MID LEVEL DPVA (WITH AN
APPROACHING WEAK WAVE) AND STRENGTHENING ATLANTIC-SOURCE LOW LEVEL
FLOW FROM THE ESE. FOLLOWING MODEL CONSENSUS... WILL SPREAD GOOD
CHANCE TO LIKELY POPS OVER THE CWA FROM THE SSW MON NIGHT THROUGH
TUE... TAPERING DOWN (BUT NOT TO ZERO) LATE TUE INTO TUE NIGHT AS A
WEAK VORTICITY CLUSTER SHIFTS TO OUR NORTHEAST... LEAVING US IN A
RELATIVE LULL. THE MODELS BEGIN TO DIFFER IN THE DETAILS BY MIDWEEK
BUT THEY SUGGEST THAT ANOTHER PASSING WEAK WAVE ALONG WITH
FLATTENING FLOW ALOFT AND A SHOT OF UPPER DIVERGENCE WITH ANOTHER
JET CORE OVER THE MIDATLANTIC WILL NECESSITATE ANOTHER UPTICK IN
POPS FOR WED. THE CORRESPONDING NORTHERN STREAM SHORTWAVE TROUGH
WILL MOVE OFF THE NEW ENGLAND COAST WED NIGHT AS HIGH PRESSURE TRIES
TO BUILD INTO OUR AREA FROM THE NNW... SO WILL TAKE POPS BACK DOWN
TO BELOW CLIMATOLOGY WED NIGHT/THU. THE LONGWAVE TROUGH OVER TX/NRN
MEX TAKES ON A NEGATIVE TILT BY FRI WITH ITS AXIS SWINGING UP INTO
THE GULF COAST... AND AS THIS INCREASE IN MOISTURE SPREADS TOWARD NC
WHILE HIGH PRESSURE CONTINUES TO NOSE IN FROM THE NORTH... THE
POTENTIAL FOR AN OVERRUNNING WEDGE EVENT IN CENTRAL NC WILL BE
INCREASING BY FRI... AND WILL TREND POPS BACK UP TO CHANCE.
THICKNESSES AND THE GENERAL PATTERN SUPPORT TEMPS WITHIN A CATEGORY
OR SO OF NORMAL... PERHAPS A BIT ABOVE NORMAL MON NIGHT TO WED AND A
BIT BELOW NORMAL WED NIGHT TO FRI. -GIH
-- End Changed Discussion --

&&

.AVIATION /18Z FRIDAY THROUGH WEDNESDAY/...
AS OF 1150 AM FRIDAY...

THERE IS A HIGH PROBABILITY OF VFR CONDITIONS ACROSS CENTRAL NC
THROUGH THE WEEKEND...AND PERSISTING INTO MONDAY.

AN APPROACHING LOW PRESSURE SYSTEM WILL INCREASE THE PROBABILITY OF
SUB VFR CEILINGS BY MONDAY NIGHT AND MORE SO TUESDAY WITH CHANCES
FOR RAIN INCREASING BY TUESDAY. ADVERSE AVIATION CONDITIONS MAY
LINGER INTO WEDNESDAY.

&&

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

$$

SYNOPSIS...WSS
NEAR TERM...WSS
SHORT TERM...BADGETT
LONG TERM...HARTFIELD
AVIATION...WSS