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000
FXUS62 KRAH 051841
AFDRAH

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RALEIGH NC
141 PM EST THU MAR 5 2015

.SYNOPSIS...A STRONG COLD FRONT WILL PUSH SOUTHWARD THROUGH THE
CAROLINAS TODAY. IN THE WAKE OF THE FRONT...ARCTIC HIGH PRESSURE
WILL BUILD INTO THE AREA ON FRIDAY AND SETTLE OVER THE REGION
FRIDAY NIGHT.

&&

.NEAR TERM /THROUGH TONIGHT/...
AS OF 1045 AM THURSDAY...

LOW LEVEL COLDER AIR TAKING ITS TIME ADVECTING SOUTH INTO CENTRAL
NC. THIS HAS RESULTED IN TEMPS RISING TO LEVELS NEAR OR SLIGHTLY
ABOVE FORECAST HIGH TEMPS SO HAVE ADJUSTED MAX TEMPS UP SEVERAL
DEGREES...ESPECIALLY ACROSS THE SOUTH.

SFC COLD FRONT CURRENTLY DROPPING SLOWLY SOUTH ACROSS THE NORTHERN
PIEDMONT. 13Z SFC ANALYSIS DEPICTS A WEAK WAVE ON THE FRONT BETWEEN
ASHEVILLE AND HICKORY. AS THIS WAVE LIFTS TO THE EAST-NORTHEAST LATE
THIS MORNING/EARLY AFTERNOON...SHOULD SEE FRONT RESUME A MORE
CONSTANT SEWD MOVEMENT ACROSS THE REGION.

12Z UPPER AIR ANALYSIS ALONG WITH THE 13Z SFC ANALYSIS SUGGEST THAT
THE SFC CHANGEOVER FROM RAIN TO A WINTRY P-TYPE COINCIDES FAIRLY
CLOSE TO THE 850MB 0 DEG C ISOTHERM. BASED ON LATEST MODEL
GUIDANCE...THIS 850MB FEATURE WILL BE JUST NORTH OF OUR CWA AT
18Z...AND ALONG A ASHEBORO-DURHAM-HALIFAX LINE AT 00Z. THUS...THE
CHANGEOVER TO WINTRY TYPE PRECIP WILL LIKELY OCCUR DURING THE
EVENING RUSH HOUR IN THE TRIAD REGION...AND BASICALLY NORTH OF THE
TRIANGLE DURING THE SAME TIME FRAME. EXPECT CHANGEOVER TO FREEZING
RAIN/SLEET MIX TO PROGRESS SOUTH INTO THE TRIANGLE AND AREAS EAST OF
THE TRIANGLE NEAR OR JUST AFTER SUNSET...AND AREAS IMMEDIATELY SOUTH
OF HIGHWAY 64/264 BY EARLY EVENING.

TONIGHT...PRECIP WILL DIMINISH WEST-TO-EAST WITH BULK OF PRECIP EAST-
NE OF OUR AREA SHORTLY AFTER MIDNIGHT. TEMPS WILL CONTINUE TO FALL
AND SHOULD RANGE FROM THE LOW-MID 20S NORTH TO THE UPPER 20S/AROUND
30 SOUTH. THIS COLD AIR WILL CAUSE ANY MOISTURE LEFT ON THE ROADS TO
FREEZE INTO A THIN LAYER OF ICE WITH THE BRIDGES/OVERPASSES/RAMPS
THE FIRST TO EXPERIENCE THE SLICK CONDITIONS. THUS...THOUGH THE
ADVISORY IS SET TO EXPIRE AT MIDNIGHT...MAY NEED TO ISSUE ANOTHER
ADVISORY (OR EXTEND THE CURRENT ADVISORY) TO ACCOUNT FOR THE BLACK
ICE. WITH TEMPS EXPECTED TO REMAIN BELOW FREEZING UNTIL 11 AM OR
NOON...THE MORNING COMMUTE MAY BE A DIFFICULT/HAZARDOUS.


&&

.SHORT TERM /FRIDAY THROUGH SUNDAY NIGHT/...
AS OF 140 PM THURSDAY...

HIGH PRESSURE WILL BUILD INTO THE AREA ON FRIDAY...AND REMAIN
OVERHEAD THROUGH THE WEEKEND...RESULTING IN DRY WEATHER. CLEARING
SKIES AND DECREASING WINDS ON FRIDAY...BECOMING CLEAR AND CALM
OVERNIGHT AND THROUGH SATURDAY NIGHT. FRIDAY WILL BE COOL...WITH
HIGHS IN THE MID 30S NORTHEAST TO LOW 40S SOUTHWEST AND OVERNIGHT
LOWS IN THE UPPER TEENS TO MID 20S. TEMPERATURES WILL BEGIN TO
MODERATE ON SATURDAY...HIGHS MAINLY IN THE LOW TO MID 50S AND LOWS
IN THE LOW 30S. CLOUDS WILL BUILD BACK IN AGAIN ON SUNDAY AS WARM
MOIST AIR BEGINS TO ADVECT IN FROM THE SOUTHWEST. NEAR SEASONAL
TEMPERATURES WILL RETURN BY SUNDAY...HIGHS IN THE MID 50S TO LOW 60S
AND LOWS IN THE UPPER 30S TO LOW 40S...ALTHOUGH THE CHANCES FOR SOME
LIGHT RAIN WILL ALSO INCREASE SUNDAY NIGHT INTO MONDAY.

&&

.LONG TERM /MONDAY THROUGH THURSDAY/...
AS OF 140 PM THURSDAY...

SPLIT FLOW REGIME CONTINUES TO CAUSE CONSIDERABLE RUN TO RUN
VARIATION IN MODEL SOLUTIONS FOR THE LONGER RANGE FORECAST. A WEAK
NORTHERN STREAM FRONT WILL BE MOVING ACROSS THE AREA ON MONDAY...
WHICH WOULD ENCOUNTER DEEPER MOISTURE ACROSS THE SOUTHEAST WITH
SCATTERED SHOWERS LATE MONDAY INTO MONDAY NIGHT. INCREASING POPS
WOULD BE SPREADING BACK INTO THE WEST TUESDAY INTO WEDNESDAY AS THE
FRONT STALLS ALONG THE COAST WITH SURFACE WAVES DEVELOPING AND
RIDING NORTHEAST UP THE FRONTAL ZONE. TEMPERATURES TUESDAY WOULD
TAKE A HIT WITH SURFACE WAVE DEVELOPMENT ENHANCING IN SITU
DAMMING...AND HIGHS WILL STALL IN THE 50S... PERHAPS A BIT LOWER IF
THE LOW LEVEL FEATURES ALLOWS FOR A MORE FAVORABLE DAMMING FEATURES
TO ALIGN.

CONFIDENCE FALLS OFF FURTHER IN THE WED AND THU PERIODS DUE TO
QUESTIONABLE INTERACTIONS BETWEEN THE NORTHERN AND SOUTHERN STREAM
SYSTEMS. AT THIS POINT...WILL INTRODUCE A SLIGHT CHANCE POP WITH
HIGHS AROUND 60 BOTH DAYS.

&&

.AVIATION /18Z THURSDAY THROUGH TUESDAY/...
AS OF 1255 PM THURSDAY...

24-HOUR TAF PERIOD: LINGERING VFR CONDITIONS AND SOUTHWEST FLOW
ACROSS THE SOUTH WILL CHANGE TO MVFR THEN IFR AND GUSTY NORTHERLY
FLOW AS THE FRONT PUSHES THROUGH. LOCATIONS BEHIND THE FRONT
CONTINUE TO EXPERIENCE GUSTY WINDS AND IFR CIGS AND VISBYS WITH
LIGHT TO MODERATE RAIN. THESE CONDITIONS ARE EXPECTED TO CONTINUE
THROUGH THIS EVENING...LONGEST AT KFAY...BEGINNING TO TAPER OFF
AROUND MIDNIGHT. A BRIEF CHANGEOVER FROM RAIN TO RAIN/SLEET AND THEN
RAIN/SLEET/SNOW IS LIKELY ACROSS THE NORTHERN HALF OF CENTRAL NC
TOWARD THE TAIL END OF THE PRECIP...WITH THE GREATEST CHANCES IN THE
NORTHEAST. EXPECT IMPROVING CONDITIONS OVERNIGHT AS THE PRECIP COMES
TO AN END. MOST...IF NOT ALL...OF CENTRAL NC SHOULD BE VFR BY
SUNRISE...OR SHORTLY THEREAFTER AND WINDS SHOULD BE NORTHERLY AND
SLOWLY DECREASING IN SPEED THROUGHOUT THE DAY.

LOOKING AHEAD: HIGH CONFIDENCE THAT VFR CONDITIONS WILL PERSIST
THROUGH THE WEEKEND ACROSS CENTRAL NC AS HIGH PRESSURE BUILDS IN AND
REMAINS OVER THE REGION. THE NEXT CHANCE FOR SUB-VFR CONDITIONS WILL
BE DURING THE OVERNIGHT HOURS SUNDAY NIGHT AND MONDAY NIGHT AS MORE
WARM MOIST AIR ADVECTS INTO CENTRAL NC.

&&

.RAH WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY FROM 3 PM THIS AFTERNOON TO MIDNIGHT
EST TONIGHT FOR NCZ007>011-021>028-038>043-078.

&&

$$

SYNOPSIS...VINCENT
NEAR TERM...BADGETT
SHORT TERM...KC
LONG TERM...MLM
AVIATION...KC