000
FXUS62 KRAH 211525
AFDRAH

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RALEIGH NC
1025 AM EST FRI NOV 21 2014

.SYNOPSIS...HIGH PRESSURE WILL BUILD OVER THE REGION TODAY AND
SATURDAY. A STRONG LOW PRESSURE SYSTEM MOVING FROM THE SOUTH PLAINS
INTO THE GREAT LAKES SUNDAY SPREADS MOISTURE OVER THE ENTIRE REGION
DURING THE DAY SUNDAY. ANOTHER COLD FRONT MOVES EAST ACROSS MUCH OF
THE MID-ATLANTIC AND CAROLINAS ON MONDAY.

&&

.NEAR TERM /THROUGH SATURDAY NIGHT/...
AS OF 1025 AM FRIDAY...

HIGH PRESSURE OVER THE OHIO VALLEY WILL CONTINUE TO RIDGE INTO THE
AREA TODAY...MOVING EAST AND THEN SOUTHWARD...SETTLING OVER NC
TONIGHT. EXPECT A FEW HIGH CLOUDS ACROSS THE NORTH THIS MORNING AS
AN UPPER LEVEL DISTURBANCE MOVES OVER THE REGION...WITH CLEAR SKIES
FOR THE AFTERNOON AND TONIGHT. THE WINDS WILL BE A BIT GUSTY THIS
MORNING AND AFTERNOON...BUT SHOULD RELAX SOME AS THE HIGH BUILDS IN.
GIVEN THICKNESSES AROUND 1300 METERS...LOWER IN THE NORTH AND
NORTHEAST AND HIGHER IN THE SOUTH...HIGHS TODAY WILL BE ABOUT 10
DEGREES OR SO COOLER THAN THURSDAY. LOWEST TEMPERATURES EXPECTED IN
THE NORTHEAST...MID 40S...AND HIGHEST ACROSS THE SOUTH...LOW 50S.
WINDS WILL BE GENERALLY NORTH AND NORTHEASTERLY DURING THE DAY...
VEERING OVERNIGHT AS THE HIGH BUILDS IN. WITH THE CLEAR SKIES AND
CALM TO LIGHT WINDS OVERNIGHT YIELDING GOOD RADIATIONAL COOLING
CONDITIONS...EXPECT LOWS TONIGHT AROUND 20 DEGREES IN THE
NORTHEAST TO MID 20S ACROSS THE SOUTH. -KC

AS OF 655 AM FRIDAY...
SATURDAY...AGAIN WITH SOME MOSTLY THIN CIRRUS AROUND...1000-850MB
THICKNESSES RISE ABOUT 30M AND HIGHS SHOULD BE 3 TO 5 DEGREES WARMER
THAN THOSE HIGHS EXPECTED FOR TODAY.

SATURDAY NIGHT...THE 850MB THETA-E GRADIENT IS FORECAST BY THE NAM
AND GFS TO JUST BE MOVING INTO THE FAR SOUTHWEST PIEDMONT BY 12Z
SUNDAY. K INDICES ARE NEAR 0 OR NEGATIVE ON THE GFS THROUGH SATURDAY
NIGHT...AND THE NAM ONLY INCREASES VALUES INTO THE TEENS IN THE FAR
SOUTHWEST CLOSE TO 12Z SUNDAY. BUFR SOUNDINGS ARE DRY AND STABLE FOR
THE NIGHT...SAVE LATE AND MAINLY ON THE NAM WHERE THE MID-LEVEL
MOISTURE IN A SHALLOW VOLUME INCREASES A LITTLE EARLIER SOUTHWEST.
QPF IS ESSENTIALLY ZERO IN CENTRAL NORTH CAROLINA ON BOTH THE NAM
AND GFS...WITH THE 0.01 LINE ON THE NAM EDGING EVER SO CLOSE TO THE
SOUTHWEST PIEDMONT BY 12Z SUNDAY. WILL MAINTAIN A DRY FORECAST
OVERNIGHT SATURDAY ALTHOUGH A SPRINKLE IS POSSIBLE VERY LATE
SATURDAY NIGHT IN THE FAR SOUTHWEST IF ANY CAN WORK THROUGH WHAT
WILL BE A DRY SUB-CLOUD LAYER. OVERNIGHT LOWS WILL PROBABLY BE
REACHED EARLY IN THE OVERNIGHT...WITH TEMPERATURES FALLING QUICKLY
EARLY AND THEN INCREASING HIGH CLOUDS IN PARTICULAR SLOWING ANY FALL
AND WITH POSSIBLY A MINOR RISE IN TEMPERATURES LATE OVER THE WESTERN
PIEDMONT. -DJF

&&

.SHORT TERM /SUNDAY AND SUNDAY NIGHT/...
AS OF 235 AM FRIDAY...

SOUTHERN STREAM TROUGH AND ATTENDANT DEEPENING SURFACE LOW OVER THE
SOUTHERN PLAINS/LOWER MS VALLEY SUNDAY MORNING WILL LIFT NORTHWARD
INTO THE UPPER GREAT LAKES SUNDAY NIGHT. WHILE THE BEST TROUGH
DYNAMICS REMAINS WEST OF THE MOUNTAINS...STRONG/DEEP GULF MOISTURE
TRANSPORT WITHIN THE TRANSIENT EASTWARD PROPAGATING WARM CONVEYOR
BELT WILL RESULT IN A WET SUNDAY-SUNDAY EVENING PERIOD ACROSS THE
CAROLINAS. AS PWATS INCREASE TO 1.5-1.75"(2 SD ABOVE NORMAL)...LOOK
FOR POPS TO QUICKLY RAMP UP SW TO NE LATE SUNDAY MORNING THROUGH THE
AFTERNOON VIA SURGE OF ISENTROPIC LIFT/WAA ATTENDANT TO A NORTHWARD
LIFTING WARM FRONT...AND FURTHER AUGMENTED BY DPVA AHEAD OF
SHORTWAVE DISTURBANCES EJECTING NEWD AHEAD OF THE AFOREMENTIONED
PRIMARY TROUGH LIFTING THROUGH THE TN AND OHIO VALLEY. EXPECT
WIDESPREAD RAINFALL AMOUNTS OF A 0.50" TO AN 1.0".  BULK OF PRECIP
LOOKS TO FALL OVER THE AREA BETWEEN 18Z SUNDAY TO 06Z MONDAY WITH
LIGHT RAIN...DRIZZLE AND/OR AREAS OF FOG THROUGH MONDAY MORNING AS
WE LOSE SATURATION ALOFT.

IMPRESSIVE LOW-LEVEL KINEMATIC WIND FIELDS FUELED BY A 60-65KT LOW-
LEVEL JET COUPLED WITH ENHANCED NEAR SURFACE HELICITY/SHEAR ALONG A
NORTHWARD RETREATING WEDGE FRONT LOOKS TO HAVE LIMITED BUOYANCY TO
WORK WITH MODELS KEEPING THE UNSTABLE PORTION OF THE WARM SECTOR
NEAR OR OFF THE SE COAST. WILL CONTINUE TO MONITOR FOR ANY INLAND
INTRUSION OF UNSTABLE AIR INTO INLAND AREAS...BUT BASED ON RECENT
TRENDS WILL KEEP THUNDER OUT OF THE FORECAST.

IN-SITU DAMMING FROM THE OFFSHORE HIGH AND WIDESPREAD RAIN WILL
RESULT IN A SLOW RISE IN TEMPERATURES DURING THE DAY ON
SUNDAY...UNTIL THE WARM FRONT LIFTS NORTH THROUGH THE AREA DURING
THE LATE AFTERNOON/EVENING HOURS. DAYTIME HIGHS WILL OCCUR AFTER
SUNSET IN MANY LOCATIONS WITH TEMPERATURES HOLDING STEADY OR QUITE
POSSIBLY WARM OVERNIGHT. DAYTIME TEMPERATURES HOLDING IN THE 50S
ACROSS THE NW PIEDMONT...WITH 60S ACROSS THE SE.

&&

.LONG TERM /MONDAY THROUGH THURSDAY/...
AS OF 235 AM FRIDAY...

MONDAY AND MONDAY NIGHT: IN THE MIDST OF THE UPSTREAM TROUGH OVER
THE CENTRAL US RELOADING...MID-LEVEL DRY AIR INTRUSION FROM THE WEST
AND THE LACK OF APPRECIABLE FORCING WILL RESULT IN MOSTLY DRY
CONDITIONS DURING THE DAY ON MONDAY. MODELS ARE STILL TRYING TO
GENERATE A LITTLE PRECIP UNTIL THE SFC COLD FRONT MOVES THE AREA
MONDAY EVENING/NIGHT...BUT RECENT MODEL TRENDS TO KEEP THE BULK OF
PRECIP EAST OF THE AREA. WILL HANG ON TO SLIGHT TO SMALL CHANCE POPS
WITH HIGHEST CHANCE IN THE EAST. LINGERING LOW-LEVEL MOISTURE
TRAPPED UNDERNEATH A STRONG MID-LEVEL CAP WILL RESULT IN CONTINUED
CLOUDY CONDITIONS ON MONDAY. EVEN WITH THIS OVERCAST/BROKEN CLOUD
DECK...TEMPERATURES IN THE WARM SECTOR WILL WARM INTO THE 60S NW TO
70S SE ON MONDAY.

TUESDAY THROUGH THURSDAY: TUESDAY IS SHAPING UP AS A DRY DAY ACROSS
THE AREA WITH THE STALLED FRONT EAST OF THE AREA WHILE WEAK HIGH
PRESSURE RIDGES IN FROM THE WEST WITH CAA IN THE WAKE OF MONDAY
NIGHT FROPA DROPPING TEMPERATURES BACK TO NEAR NORMAL. THERE IS THEN
A BIT OF UNCERTAINTY REGARDING THE APPROACH OF THE NEXT BATCH OF
SHORTWAVE ENERGY TRAVERSING EASTWARD WITHIN THE BASE OF THE LONGWAVE
TROUGH AND ASSOCIATED SFC CYCLOGENESIS ALONG THE OFFSHORE FRONTAL
ZONE. THE LATEST GFS AND EC HAVE TRENDED WETTER DURING THE TUESDAY
NIGHT-WEDNESDAY PERIOD...WITH PRECIP DEVELOPING INLAND IN THE COOL
SECTOR. FOR NOW...WILL ADD A SLIGHT CHANCE POPS TO COASTAL/EASTERN
PORTIONS OF THE FORECAST AREA...WITH TEMPERATURES RETURNING TO BELOW
NORMAL AS THE UPPER TROUGH MOVES INTO THE EASTERN US.

&&

.AVIATION /12Z FRIDAY THROUGH TUESDAY/...
AS OF 655 AM FRIDAY...

FOR THE 12Z VALID TAF PERIOD...VFR CONDITIONS CONTINUE WITH MOSTLY
FEW-TO-SCATTERED HIGH CLOUDS. THIS MORNING...A BRIEF PERIOD OF
BROKEN HIGH CLOUDS IS POSSIBLE BEFORE CLEARING LATER IN THE MORNING.
THE SURFACE GRADIENT WILL INCREASE THIS MORNING HOURS SUCH THAT
MODEL SOUNDINGS SUGGEST A FEW NORTHERLY GUSTS INTO THE TEENS KNOTS
WITH MIXING THIS MORNING. AS THE SURFACE HIGH BUILDS OVERHEAD...
WINDS SHOULD BECOME LIGHTER AS THEY VEER LATER IN THE DAY WITH MANY
CALM OR VERY LIGHT SURFACE WINDS TAKING PLACE AFTER SUNSET.

BEYOND THE 12Z VALID TAF PERIOD...VFR CONDITIONS CONTINUE SATURDAY
THROUGH SATURDAY NIGHT. AS MOISTURE AND PRECIPITATION SPREAD
NORTHEAST OVER CENTRAL NORTH CAROLINA SUNDAY...CONDITIONS SHOULD
DETERIORATE THROUGH MVFR TO IFR IN MOST PLACES AND CONTINUE SUB-VFR
AT LEAST THROUGH SUNDAY NIGHT. AREAS OF MVFR CEILINGS ARE POSSIBLE
INTO MONDAY WITH GUSTY SOUTHWEST WINDS WHICH COULD REACH 40KT BY
2000FT ALOFT IF THE GFS MODEL VERIFIES. VFR CONDITIONS SHOULD RETURN
BY TUESDAY WITH SOME AREAS OF MID-LEVEL CLOUDS OVER A LIGHTER
SURFACE WIND VEERING NORTHERLY BEHIND A COLD FRONT THAT MOVES
THROUGH LATE MONDAY. THERE IS A CHANCE OF LIGHT RAIN MAINLY TOWARD
KFAY AND KRWI LATE TUESDAY ON THE WEST SIDE OF LOW PRESSURE THAT
MOVES ALONG THE FRONT WHICH WILL LOCATED THEN JUST OFF THE CAROLINA
COAST.

&&

.CLIMATE...

RECORD LOW:   GSO  RDUFAY

SAT 11/22 - 13 IN 1914    21 IN 2008    20 IN 2000

&&

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

&&

$$

SYNOPSIS...DJF
NEAR TERM...KC/DJF
SHORT TERM...CBL
LONG TERM...CBL
AVIATION...DJF
CLIMATE...RAH

NWS RAH Office Area Forecast Discussion