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-- Discussion containing changed information from previous version are highlighted. --
000
FXUS62 KRAH 300508
AFDRAH

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RALEIGH NC
108 AM EDT WED JUL 30 2014

.SYNOPSIS...WEAK HIGH PRESSURE WILL PERSIST ACROSS THE AREA TODAY
AND TONIGHT...THEN WEAKEN ON THURSDAY. DEEP MOISTURE WILL GRADUALLY
RETURN TO THE REGION THURSDAY NIGHT FRIDAY AS AN UPPER LEVEL TROUGH
APPROACHES FROM THE WEST... AND AN ATTENDANT COASTAL FRONT MOVES
INLAND ACROSS THE CENTRAL CAROLINAS.

&&

.NEAR TERM /THROUGH WEDNESDAY NIGHT/...
AS OF 908 PM TUESDAY...

...NEAR RECORD LOWS TONIGHT...

THE SUNSET WAS ONLY 45 MINUTES AGO AND ALREADY THE TEMPERATURES WERE
REPORTED TO BE IN THE MID TO UPPER 60S ACROSS OUR NE ZONES
INCLUDING: THE REPORTS FROM LOUISBURG... TARBORO... HALIFAX... AND
HENDERSON. THERE WERE SOME MID 70S REPORTED FROM THE SOUTHERN
PIEDMONT AND SANDHILLS. THE LATEST IR SATELLITE DATA INDICATED SOME
PATCHY MID LEVEL CLOUDS WITH BASES AROUND 10K FEET. RAOB DATA AT
00Z/30 JULY FROM GREENSBORO INDICATED THE MID LEVEL INVERSION
CONTINUED TO EXIST NEAR H7 WHICH CONTINUED TO TRAP SOME MOISTURE AT
THAT LEVEL. TRENDS DO SUGGEST A DECREASE IN AREAL COVERAGE OF THE
PATCHY CLOUDINESS IN THE PAST 3 HOURS. THESE TRENDS ARE SUPPORTED IN
THE LATEST MODEL GUIDANCE WHICH GENERALLY SUGGESTS MOSTLY CLEAR
SKIES OVERNIGHT. WITH THIS IN MIND AND CONSIDERING THE DRY AIR NEAR
THE SURFACE (DEW POINTS 50-60 DEGREES)... WE WILL LOWER MINIMUM
TEMPERATURES A FEW DEGREES FROM PREVIOUS FORECASTS.

THIS WILL NOW YIELD LOWS OF LOWER 50S NORTH AND EAST (RURAL AREAS)
INTO THE LOWER 60S AROUND THE URBAN AREAS OF FAYETTEVILLE. CURRENT
PROJECTIONS INDICATE LOWS OF 59 AT RALEIGH... 58 AT GREENSBORO...
AND 61 AT FAYETTEVILLE. THESE FORECASTS WILL BE FAIRLY CLOSE (2-3
DEGREES) TO THE DAILY RECORD LOWS FOR JULY 30. THEY INCLUDE: RALEIGH
56 DEGREES SET IN 1946... GREENSBORO 56 DEGREES SET IN 1946... AND
FAYETTEVILLE 59 SET IN 1920.

&&

.SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/...
AS OF 310 PM TUESDAY...

WEDNESDAY WILL HAVE CONTINUED SUBSIDENCE KEEPING DRY CONDITIONS IN
PLACE WITH A SLIGHT WARMING TREND BUT STILL IN THE LOW TO MID 80S
FOR HIGHS WITH UPPER 50S TO LOW 60S ONCE AGAIN FOR MINIMUM
TEMPERATURES. SCATTERED TO BROKEN CLOUD COVER IN THE 5-8 KFT RANGE
WILL HAVE THE HEAVIEST CONCENTRATION IN EASTERN AREAS OF THE CWA
WHICH MAY HELP KEEP MAX TEMPS DOWN A DEGREE OR TWO FROM FORECASTED
HIGHS.DEEP UPPER TROUGHING OVER THE EASTERN HALF OF THE US WILL
CONTINUE THURSDAY...THOUGH WITH A BRIEF RELAXATION AND HEIGHT RISES
ALOFT BETWEEN A SHORTWAVE LIFTING OFF TO THE NORTHEAST AND ENERGY
DIVING THROUGH THE PLAINS STATES.  THICKNESSES RISE ABOUT 10M OVER
WEDNESDAY...STARTING OUT AT 1395M THURSDAY MORNING...WHICH SHOULD
YIELD 83-87 UNDER MAINLY PARTLY CLOUDY SKIES.  DEWPOINTS STILL IN
THE 50S AND LOWER 60S WILL LIMIT CAPE TO A COUPLE HUNDRED J/KG OR
LESS...THOUGH A LITTLE BETTER MOISTURE AT THE TOP OF THE BOUNDARY
LAYER MAY HELP ENHANCE CLOUD COVER ACROSS THE SOUTHERN PORTIONS OF
THE AREA...ESPECIALLY ALONG THE SEABREEZE.  ANY SHOWERS AND STORMS
SHOULD REMAIN SOUTH OF THE AREA.  CLOUDS...ESPECIALLY MID AND HIGH
CLOUDS WILL CONTINUE TO INCREASE THURSDAY NIGHT AS A SHORTWAVE DIVES
THROUGH THE DEEP SOUTH.  LOWS WILL BE MOSTLY IN THE MID 60S.

&&

.LONG TERM /FRIDAY THROUGH TUESDAY/...
AS OF 310 PM TUESDAY...

THE FRIDAY THROUGH TUESDAY PERIOD IS ONE OF MIXED CONFIDENCE.
MODELS ARE IN GOOD AGREEMENT THAT THE MEAN UPPER TROUGH AXIS WILL
REMAIN WEST OF THE APPALACHIANS...PLACING NC IN SOUTHWESTERLY FLOW
ALOFT AND IN THE RIGHT ENTRANCE REGION OF AN UPPER JET ALONG THE
SPINE OF THE MOUNTAINS. AN INVERTED COASTAL TROUGH WILL SLOWLY
MEANDER WESTWARD OVER THE WEEKEND AND THEN LIKELY WASH OUT BY EARLY
NEXT WEEK AS THE TROUGH WEAKENS AND THE WESTERN ATLANTIC RIDGE
BUILDS WESTWARD.  THIS WILL CAUSE PW TO CONTINUE TO INCREASE TO
UPWARDS OF TWO INCHES BY SUNDAY.  WHILE THIS POINTS TOWARD A WET
WEEKEND...CONFIDENCE IS LOW WHEN IT COMES TO BEST TIME FRAME FOR
PRECIP.  ON FRIDAY...MODELS ARE SHOWING A DISTURBANCE EMANATING FROM
CONVECTION OVER THE HIGH PLAINS THAT SWEEPS AROUND THE BASE OF THE
TROUGH AND THEN LIFTS ACROSS OUR REGION.  ITS HARD TO PUT MUCH FAITH
IN SUCH A FEATURE THREE DAYS OUT...BUT ALL MODELS HAVE SHOWN AN
INCREASE IN QPF FOR FRIDAY...SO HAVE INCREASED POPS INTO THE 40-50
RANGE.  HOWEVER...BEYOND FRIDAY THERE IS VERY LITTLE TO KEY ON FOR
FORCING OTHER THAN THE AFOREMENTIONED JET AND WEAKENING COASTAL
TROUGH.  THUS...WILL HAVE CHANCE POPS IN EACH DAY BE KEEP THEM BELOW
50 PERCENT UNTIL IT BECOMES MORE APPARENT WHICH DAY WILL BE FAVORED.
 THUNDER POTENTIAL LOOKS LIMITED FRIDAY AND SATURDAY GIVEN LIMITED
INSTABILITY WITH WEAK LAPSE RATES ALOFT AND RELATIVELY COOL DAYTIME
TEMPS IN THE UPPER 70S AND LOWER 80S.  A WARMING TREND SHOULD ENDUE
BY SUNDAY AND MONDAY AS THE UPPER RIDGE AND BERMUDA HIGH STRENGTHEN
TO OUR EAST.

&&

.AVIATION /06Z WEDNESDAY THROUGH SUNDAY/...
AS OF 100 AM WEDNESDAY...

24-HR TAF PERIOD: UPPER DISTURBANCES ROTATING THROUGH THE BASE OF THE
DEEP UPPER LEVEL TROUGH IN PLACE OVER THE REGION WILL RESULT IN ISOLATED
SHOWERS ACROSS THE AREA. OTHERWISE...DRY AIR IN THE LOW-LEVELS WILL SUPPORT
VFR CONDITIONS THROUGH THE TAF PERIOD.

LOOKING AHEAD: EXPECT AN INCREASING POTENTIAL FOR ADVERSE AVIATION
CONDITIONS ASSOCIATED WITH LOW CEILINGS AND SCATTERED TO WIDESPREAD
CONVECTION FRIDAY NIGHT THROUGH THE WEEKEND AS A COASTAL FRONT
RETROGRADES INLAND INTO CENTRAL PORTIONS OF THE STATE...IN ADVANCE
OF AN UPPER LEVEL TROUGH APPROACHING FROM THE WEST.

&&

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

&&

$$

SYNOPSIS...VINCENT
NEAR TERM...32
SHORT TERM...ELLIS/BLS
LONG TERM...BLS
AVIATION...CBL/VINCENT