Area Forecast Discussion
Issued by NWS Raleigh/Durham, NC

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FXUS62 KRAH 030000
AFDRAH

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RALEIGH NC
800 PM EDT TUE JUN 2 2015

.SYNOPSIS...A MID LEVEL LOW PRESSURE TROUGH AND SURFACE COLD FRONT
EXTENDING ALONG THE CENTRAL AND SOUTHERN APPALACHIANS WILL DRIFT
SLOWLY EASTWARD THEN STALL OVER THE CAROLINAS THROUGH THE REST OF
THE WORK WEEK... BRINGING UNSETTLED WEATHER.
&&

.NEAR TERM /THROUGH TONIGHT/...
AS OF 245 PM TUESDAY...

TEMPERATURES STARTING TO RECOVER ACROSS THE AREA IN THE WAKE OF
MORNING CONVECTION WITH SOUTHERN SITES STARTING TO CREEP INTO THE
LOWER 80S. A SURGE OF LOW LEVEL MOISTURE NOW MOVING THROUGH THE
CHARLOTTE METRO AREA WILL ADVECT NORTHWESTWARD AND NEW CONVECTION
SHOULD BEGIN TO BREAK OUT ACROSS THE WESTERN PIEDMONT OVER THE NEXT
COUPLE OF HOURS. FORECAST SOUNDINGS INDICATE THAT BULK SHEAR WILL BE
BETWEEN 20-30 KTS FOR THE NEXT FEW HOURS BEFORE DROPPING OFF AGAIN
CLOSER TO SUNSET. SPC ANALYSIS SHOWS ABOUT 1000 J/KG OF MIXED LAYER
CAPE AVAILABLE TO NEW CONVECTION. WITH THE FREEZING LEVEL NEAR 12
KFT IN THE TRIAD THIS WOULD BE THE MOST LIKELY SPOT TO SEE SMALL
HAIL BUT SKINNY CAPE THROUGH THE HAIL GROWTH ZONE MAKES THIS FAIRLY
UNLIKELY BUT POSSIBLE. WIND THREAT IS NOT ALL THAT GREAT EITHER BUT
DCAPE VALUES AROUND 700 IN THE SOUTHWEST SUGGEST THAT AT LEAST SOME
SMALL WET MICROBURSTS WITH GUSTS IN THE 30-40 MPH RANGE ARE
POSSIBLE. THAT LEAVES THE BIGGEST THREAT OF THE DAY TO BE HEAVY
RAIN...ESPECIALLY IN THE SW WHERE ANTECEDENT CONDITIONS ARE FAIRLY
WET AND 1 HR FLASH FLOOD GUIDANCE IS LOWER.

OFF TO THE EAST THE SEA BREEZE IS PUSHING A BAND OF CONVECTION
FURTHER INLAND WHICH WILL MOST LIKELY AFFECT EASTERN COUNTIES LATER
THIS AFTERNOON/EVENING. SIMILAR CONDITIONS IN THIS AREA TO THE NW
PIEDMONT (ONLY WITH A MUCH HIGHER FREEZING LEVER) ALSO SUGGEST THAT
SOME STRONGER STORMS WILL BE POSSIBLE HERE AS WELL. NORTH CENTRAL
AREAS OF THE CWA HAVE SEEN THE BIGGEST REDUCTION IN TEMPERATURE DUE
TO EARLIER CONVECTION AND MAY TAKE SOME TIME TO RECOVER BUT THE SAME
INSTABILITY/SHEAR NUMBERS HERE MAKE CONVECTION POSSIBLE LATER THIS
AFTERNOON/EVENING AS WELL. TEMPERATURES THIS AFTERNOON IN THE UPPER
70S TO MID 80S.

OVERNIGHT TONIGHT CHANCE FOR SHOWERS AND STORMS WILL LINGER THROUGH
THE EVENING AS CONVECTING ALLOWING MODELS INDICATE MORE OF A PUSH
FROM THE FRONTAL ZONE TO THE WEST. CEILINGS ARE ALSO EXPECTED TO
DROP IN MOST LOCATIONS TO AT LEAST IFR IF NOT LIFR BETWEEN 9-12Z.
LOWS IN THE MID 60S.

&&

.SHORT TERM /WEDNESDAY AND WEDNESDAY NIGHT/...
AS OF 245 PM TUESDAY...

WEDNESDAY THE UPPER LEVEL LOW WILL MOVE MORE DIRECTLY OVERHEAD AND A
SURFACE HIGH OVER NEW ENGLAND WILL HELP FLOW TO BECOME MORE
NORTHEASTERLY ACROSS THE STATE. THIS WILL YIELD MUCH COOLER
CONDITIONS AND A CREATE A SITUATION WHERE CEILINGS WILL NOT BE ABLE
TO RECOVER TO MUCH MORE THAN MVFR LEVELS DURING THE DAY. LIFT
GENERATED BY THE UPPER LOW WILL HELP TO KEEP STEADY PRECIP CHANCES
THROUGH THE DAY OVER MUCH OF THE AREA BUT INSTABILITY WILL BE VERY
WEAK AND SHEAR VALUES ONLY AROUND 10 KTS. HIGHS WILL ONLY MAKE IT TO
THE LOWER 70S IN THE TRIAD WITH NEAR 80 DEGREES IN EASTERN COUNTIES.

FRONT WILL CONTINUE TO MOVE EASTWARD WEDNESDAY NIGHT AND LOWS COULD
MAKE IT INTO THE UPPER 50S IN THE TRIAD FOR THE FIRST TIME IN A
WHILE. POINTS EAST WILL STILL SEE LOW TO MID 60S HOWEVER. CHANCES
FOR LOW STRATUS WILL ONCE AGAIN BE FAVORABLE DURING THE OVERNIGHT
HOURS WEDNESDAY NIGHT INTO THURSDAY WITH LINGERING CHANCES FOR RAIN
CONTINUING INTO THURSDAY.

&&

.LONG TERM /THURSDAY THROUGH TUESDAY/...
AS OF 300 PM TUESDAY...

WET WEATHER APPEARS LIKELY TO LINGER THROUGH THU... WITH THE
SYNOPTIC CONFIGURATION SIMILAR TO WED WITH A NARROW STABLE SURFACE
WEDGE OVER THE WRN PIEDMONT AND A BROAD FRONTAL ZONE OVER THE
COASTAL PLAIN... ALTHOUGH THE MID LEVEL LOW TO OUR WEST WILL HAVE
DRIFTED SLIGHTLY CLOSER... INTO THE FAR WRN CAROLINAS. MARGINAL TO
MODERATE INSTABILITY IS EXPECTED (1000-2000 J/KG AREAWIDE ON THE
NAM... SLIGHTLY LESS ON THE GFS) WITH SIMILAR WEAK DPVA ROTATING
AROUND THE E/NE SIDE OF THE LOW... POSSIBLE UPPER DIVERGENCE (MAINLY
NE)... PW AROUND 150% OF NORMAL... AND ONSHORE-DIRECTED LOW LEVEL
FLOW FOCUSED ALONG THE FRONTAL ZONE. MODELS ARE GENERATING THE
GREATEST AND MOST WIDESPREAD QPF OVER THE ERN AND NRN SECTIONS...
NEAREST THE BOUNDARY... REASONABLE GIVEN THE POTENTIAL FOR SOME MID
LEVEL DRYING TO WORK INTO SW SECTIONS. EXPECT ANOTHER ROUND OF
SCATTERED (SW) TO NUMEROUS (ELSEWHERE) SHOWERS AND EMBEDDED
STORMS... PEAKING IN THE AFTERNOON AND EVENING. THICKNESSES ARE
EXPECTED TO BE 15-20 M BELOW NORMAL ESPECIALLY BENEATH THE WEDGE
AXIS... AND FACTORING IN THE CLOUDS AND PRECIP... WILL KEEP HIGHS
BELOW NORMAL... MID 70S TO AROUND 80. WITH LINGERING ELEVATED
INSTABILITY AND ABOVE NORMAL PW PERSISTING OVERNIGHT... WILL TREND
PRECIP CHANCES DOWN BUT NOT OUT THU NIGHT AS THE BY-NOW-WEAKENING
UPPER LOW STARTS TO SHIFT OVERHEAD. LOWS IN THE LOW-MID 60S.

TEMPS SHOULD REMAIN COOLER THAN CLIMO FRI... AS THE MID LEVEL LOW
AND ASSOCIATED MID LEVEL TROUGH AND SURFACE FRONT ZONE ALL PUSH
SLOWLY EAST AND OFFSHORE. LOW LEVEL MOISTURE WILL BE SLOW TO
DISPERSE BASED ON THE WEAK LOW LEVEL FLOW... BUT ONCE THE
OVERNIGHT/MORNING STRATUS BREAKS UP AND LIFTS... WE SHOULD SEE
PARTIAL CLEARING AND SOME RECOVERY IN THICKNESSES. MARGINAL TO
MODERATE INSTABILITY AND FAIRLY WEAK DEEP LAYER SHEAR ARE EXPECTED
TO PERSIST... BUT OTHERWISE WE SHOULD SEE A BRIEF LULL IN FORCING
FOR ASCENT BEHIND THE DEPARTING TROUGH. WILL KEEP NEAR-CLIMO 30-40%
CHANCES MAINLY EAST. EXPECT HIGHS AROUND 80 TO THE LOWER 80S. MODELS
ARE UNANIMOUS IN SHOWING LATE-DAY MOUNTAIN CONVECTION... WHICH MAY
DROP SLOWLY SE INTO THE NW CWA LATE EVENING THROUGH THE OVERNIGHT
HOURS FRI NIGHT BASED ON THE WEAK NW FLOW. WE`RE ALSO LIKELY TO SEE
FRIDAY`S MIDWEST MCS ACTIVITY (OR ITS REMNANT MCV) DROP THROUGH THE
WRN/CENTRAL OH VALLEY TOWARD THE SRN APPALACHIANS FRI EVENING AND
OVERNIGHT... ALTHOUGH AT THIS PACE THIS FEATURE WOULD BE MORE LIKELY
TO AFFECT US ON SAT. AT ANY RATE... WILL INDICATE A BETTER CHANCE OF
SHOWERS AND ISOLATED STORMS OVER THE NW CWA OVERNIGHT WITH JUST A
SLIGHT CHANCE ELSEWHERE. LOWS AGAIN IN THE LOWER-MID 60S.

IF THE AFOREMENTIONED MCV COMES TO PASS AND MOVES AS MODELS
SUGGEST... IT SHOULD MOVE THROUGH THE CAROLINAS ON SAT...
POTENTIALLY RELOADING THE WEAK TROUGH AXIS BACK OVER THE CAROLINAS.
BUT WITH THE OVERALL NOAM AND WRN ATLANTIC FLOW WEAKENING AND
FLATTENING AT THESE LATITUDES FRI/SAT... IT`S DIFFICULT TO PINPOINT
AND TRACK SPECIFIC FEATURES THIS FAR OUT. BY SUNDAY... THE GFS/ECMWF
TAKE POTENT NRN STREAM ENERGY ESE THROUGH THE UPPER MIDWEST AND
GREAT LAKES TO THE NORTHEAST SUN/MON... AMPLIFYING MID LEVEL
TROUGHING OVER THE EASTERN STATES AND LIKELY INCREASING SHEAR ENOUGH
OVER OUR AREA FOR AN INCREASED RISK OF STORMS MON INTO TUE. AFTER
GENERALLY STABLE CONDITIONS SUNDAY (BEHIND THE POTENTIAL DEPARTING
MCV BUT AHEAD OF THIS DIGGING TROUGH)... THE GFS DEPICTS RISING
MUCAPE VALUES EACH DAY MON/TUE TO 1000-2500 J/KG. WILL RAMP UP LATE-
DAY STORM CHANCES (SOME OF WHICH COULD BE STRONG) MON/TUE. TEMPS
SHOULD REBOUND BACK TO NEAR NORMAL BY THAT TIME. -GIH

&&

.AVIATION /00Z WEDNESDAY THROUGH SUNDAY/...
AS OF 800 PM TUESDAY...

SCATTERED SHOWERS AND STORMS CONTINUE ACROSS PORTIONS OF CENTRAL N
AS AN UPPER LOW SLOWLY APPROACHES FROM THE WEST AND A COLD FRONT
DRIFTS SOUTH INTO THE AREA FROM NC.   STORMS WILL BE POSSIBLE AROUND
KINT/KGSO FOR A FEW MORE HOURS...THROUGH ROUGHLY 04Z...AS THE FRONT
PUSHES THROUGH THE AREA.  BEHIND THE FRONT...CEILINGS ARE EXPECTED
TO LOWER TO MVFR AND EVENTUALLY IFR...THOUGH SOME LIFR CEILINGS ARE
POSSIBLE...AS A NORTHEASTERLY WIND DEVELOPS.  THE EXCEPTION MAY BE
KFAY WHERE CEILINGS ARE ONLY EXPECTED TO FALL TO MVFR IF THE FRONT
STALLS NORTH OF THE TERMINAL. SCATTERED SHOWERS WILL CONTINUE TO BE
POSSIBLE OVERNIGHT...ESPECIALLY AT EASTERN SITES.

SCATTERED SHOWERS AND STORMS WILL BE POSSIBLE AGAIN ON
WEDNESDAY...WITH CEILINGS EXPECTED TO REMAIN AT MVFR LEVELS DURING
THE DAYS.

OUTLOOK...AN UPPER LEVEL LOW MOVING OVER THE AREA FOLLOWED BY
SEVERAL SHORT WAVES IN THE UPPER LEVEL PATTERN ADVECTING OVER THE
AREA WILL KEEP CONDITIONS UNSETTLED FOR THE FORESEEABLE FUTURE WITH
DAILY CHANCES FOR PRECIPITATION AND SUB-VFR CONDITIONS.

&&

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

&&

$$

SYNOPSIS...HARTFIELD
NEAR TERM...ELLIS
SHORT TERM...ELLIS
LONG TERM...HARTFIELD
AVIATION...ELLIS/22


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