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-- Discussion containing changed information from previous version are highlighted. --
000
FXUS62 KRAH 221609
AFDRAH

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RALEIGH NC
1205 PM EDT TUE APR 22 2014

.SYNOPSIS...A COLD FRONT WILL APPROACH FROM THE WEST THIS EVENING
THEN CROSS THE REGION TONIGHT. HIGH PRESSURE WILL BUILD IN FROM THE
NORTHWEST ON WEDNESDAY AND THURSDAY. ANOTHER COLD FRONT WILL
APPROACH FROM THE WEST ON FRIDAY.
&&

.NEAR TERM /THROUGH TONIGHT/...
AS OF 1130 AM TUESDAY...

A SURFACE TROUGH WILL MOVE THROUGH THE AREA THIS AFTERNOON IN
ADVANCE OF AN UPPER LEVEL TROUGH AND ATTENDANT COLD FRONT TRACKING
THROUGH THE AREA THIS EVENING. DCVA AND LOW LEVEL CONVERGENCE
COMBINED WITH DIURNAL HEATING...WEAK MOISTURE ADVECTION AND MARGINAL
DIURNAL DESTABILIZATION WILL RESULT IN A POTENTIAL FOR SCATTERED
SHOWERS BETWEEN 19-22Z IN THE TRIAD AND 21-02Z IN THE TRIANGLE AND
COASTAL PLAIN...SIMILAR TO WHAT HIGH-RES CONVECTION ALLOWING MODELS
SUCH AS THE HRW-NMM INDICATE. THUNDER APPEARS UNLIKELY GIVEN
MARGINAL THERMODYNAMIC PROFILES...THOUGH WILL BE POSSIBLE EAST OF
HWY 1 IF DESTABILIZATION...DCVA AND LOW-LEVEL CONVERGENCE ARE
FAVORABLY JUXTAPOSED. THE POSTFRONTAL AIRMASS THAT FOLLOWS THE COLD
FRONT IS STABLE AND BRINGING IN LOW DEW POINTS FROM THE NORTHWEST
WHICH WILL QUICKLY DRY OUT THE AREA AND SUPPRESS ANY FURTHER
PRECIPITATION BEHIND THE FRONT. THERE IS A POTENTIAL FOR LINGERING
CLOUDS BEHIND THE FRONT AS THE DRY AIR IS MIXED FROM ALOFT DOWN TO
THE SURFACE. ANY LINGERING CLOUDS WILL CLEAR OUT SOON AFTER THE COLD
FRONTAL PASSAGE LEADING TO CLEAR SKIES TONIGHT. -SSR/VINCENT

&&

.SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/...
-- Changed Discussion --
AS OF 1200 PM TUESDAY...

...SEE FIRE WEATHER SECTION BELOW FOR POTENTIAL WEATHER HAZARDS FOR
WEDNESDAY AFTERNOON AND EVENING...

RATHER WINDY CONDITIONS ARE EXPECTED WEDNESDAY AS THE PRESSURE
GRADIENT REMAINS TIGHT. STRONG COOL AND DRY ADVECTION WILL BE DRIVEN
BY NORTHWEST WINDS AT 15-25 MPH WITH GUSTS TO 35 MPH. THIS DRYING
PROCESS ALONG WITH THE WINDS AND LOW RELATIVE HUMIDITY VALUES
EXPECTED MAY LEAD TO A CRITICAL FIRE WEATHER DAY WEDNESDAY. WINDS
WILL DIMINISH TO LESS THAN 10 MPH WEDNESDAY NIGHT AS THE HIGH
BECOMES POSITIONED OVERHEAD LATE. A RATHER QUICK RETURN SW FLOW IS
EXPECTED TO DEVELOP THURSDAY (BUT WITH MUCH LESS VELOCITY
- 8-12 MPH DURING THE AFTERNOON). THIS INFORMATION WILL BE
COLLABORATED WITH THE FORESTRY OFFICIALS.

OTHERWISE... TEMPERATURES SHOULD AVERAGE 5-10 DEGREES BELOW THE 30
YEAR NORMALS WEDNESDAY THROUGH THURSDAY. SENSIBLE WEATHER... SUNNY
AND WINDY WEDNESDAY. HIGHS IN THE UPPER 60S TO MID 70S (SE). CLEAR
AND CHILLY WEDNESDAY NIGHT. LOWS IN THE UPPER 30S TO LOWER 40S.
MOSTLY SUNNY AND MILD THURSDAY. HIGHS IN THE LOWER 70S. BECOMING
MOSTLY CLOUDY THURSDAY NIGHT. LOWS IN THE UPPER 40S NE TO MID 50S.
-- End Changed Discussion --

&&

.LONG TERM /FRIDAY THROUGH MONDAY/...
-- Changed Discussion --
AS OF 310 AM TUESDAY...

MODELS HINT AT A FEW SHOWERS OVER THE WESTERN PIEDMONT FRIDAY
MORNING AS THE UPPER TROUGH AND ASSOCIATED DCVA MOVE OUT AHEAD OF
THE MAIN FRONTAL ZONE. BY THE TIME THE FRONT MOVES INTO CENTRAL NC
FRIDAY AFTERNOON/EVENING IT WILL BE RATHER WEAK AND THE MID-LEVEL
FLOW WILL BE WESTERLY.  LOW-LEVEL MOISTURE RETURN WILL BE BETTER
AHEAD OF THIS FRONT WTH DEWOINTS POTENTIALLY IN THE UPPER 50S AND
LOWER 60S...AND SO SOME DESTABILIZATION IS LIKELY FRIDAY AFTERNOON.
DEEP LAYER SHEAR WILL BE MARGINALLY STRONG...UP TO 35KT...AND WHILE
A FEW STRONG STORMS ARE POSSIBLE...THE BEST SHEAR AND INSTABILITY
MAY NOT LINE UP FOR MUCH SEVERE THREAT. HIGHS WILL BE IN THE MID AND
UPPER 70S. LOWS FRIDAY NIGHT MID TO UPPER 50S.THE COLD FRONT WILL
MOVE THROUGH THE AREA FRIDAY EVENING AND THEN ESSENTIALLY WASH OUT
AS SOUTHWESTERLY FLOW REDEVELOPS ON SATURDAY AHEAD OF A STRONGER
SECONDARY FRONTAL ZONE MOVES INTO THE MID ATLANTIC STATES.  MODELS
SHOW CENTRAL NC REMAINING MOSTLY WITHIN THE WARM SECTOR THROUGH THE
WEEKEND...WITH THE FRONT HOLDING JUST TO OUR NORTH.  THERE ARE
RATHER LARGE MODEL DIFFERENCES REGARDING PRECIP DEVELOPING ALONG THE
FRONT AS A COUPLE OF SHORTWAVES ROTATE ACROSS THE GRAT LAKES REGION.
 A MORE SIGNIFICANT STORM SYSTEM IS FORECAST TO DEVELOP OVER THE
SOUTH/CENTRAL PLAINS ON SUNDAY...WHICH SHOULD EVENTUALLY SPREAD
BETTER PRECIP CHANCES ACROSS OUR REGION BY MONDAY INTO TUESDAY.
-- End Changed Discussion --

&&

.AVIATION /18Z TUESDAY THROUGH SUNDAY/...
AS OF 1145 AM TUESDAY...

VFR CONDITIONS WILL LARGELY PREVAIL THROUGH THE TAF PERIOD. A SHORT
PERIOD OF MVFR CONDITIONS WILL BE POSSIBLE IN ASSOC/W ISOLD TO SCT
SHOWER ACTIVITY DEVELOPING IN ADVANCE OF AN APPROACHING FRONT THIS
AFTERNOON AND EVENING. A TEMPO GROUP WILL BE INCLUDED TO ACCOUNT FOR
SUCH A POTENTIAL.

LOOKING AHEAD: VFR CONDITIONS WILL RULE THROUGH THURSDAY IN THE WAKE
OF THE COLD FRONTAL PASSAGE TONIGHT. SUB-VFR CEILINGS WILL BE
POSSIBLE IN ASSOC/W SOUTHERLY RETURN FLOW THU NIGHT...IN ADVANCE OF
THE NEXT COLD FRONT CROSSING THE REGION FROM THE WEST ON FRIDAY...
FOLLOWED BY VFR CONDITIONS AGAIN ON SAT. -VINCENT

&&

.FIRE WEATHER /WEDNESDAY INTO WEDNESDAY EVENING...
-- Changed Discussion --
AS OF 1200 PM TUESDAY...

NORTHWEST WINDS AT 15 TO 25 MPH WILL GUST TO BETWEEN 30 AND 35 MPH
BEHIND A COLD FRONT WEDNESDAY AFTERNOON INTO EARLY WEDNESDAY
EVENING. LOW MINIMUM RELATIVE HUMIDITIES OF 20 TO 25 PERCENT CAN BE
EXPECTED WEDNESDAY AFTERNOON. FINE FUEL MOISTURE LEVELS WILL DRY
OUT. WE MAY NEED AN INCREASED FIRE DANGER STATEMENT OR A FIRE
WEATHER WATCH IN LATER FORECASTS AFTER COLLABORATION WITH THE
FORESTRY OFFICIALS.

.RAH WATCHES/WARNINGS/ADVISORIES... NONE.
-- End Changed Discussion --

&&

$$

SYNOPSIS...BADGETT
NEAR TERM...VINCENT
SHORT TERM...BADGETT
LONG TERM... SMITH
AVIATION...HARTFIELD
FIRE WEATHER...BADGETT