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-- Discussion containing changed information from previous version are highlighted. --
000
FXUS62 KRAH 310614
AFDRAH

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RALEIGH NC
115 AM EST SAT JAN 31 2015

.SYNOPSIS...
-- Changed Discussion --
HIGH PRESSURE CONTINUES TO BUILD OVER THE REGION TODAY.
THE CENTER OF THE HIGH MOVES OFFSHORE TONIGHT AHEAD OF A LOW
PRESSURE SYSTEM THAT MOVES INTO THE MID-ATLANTIC MONDAY MORNING. THE
TRAILING COLD FRONT PUSHES EAST OF THE CAROLINAS MONDAY...FOLLOWED
BY HIGH PRESSURE AGAIN FOR THE MIDDLE OF NEXT WEEK.
-- End Changed Discussion --

&&

.NEAR TERM /TODAY AND TONIGHT/...
-- Changed Discussion --
AS OF 115 AM SATURDAY...

ASIDE FROM SOME JET-STREAK CIRRUS OVER PART OF CENTRAL NORTH
CAROLINA ON THE LATEST IR SATELLITE IMAGES...CLEAR CONDITIONS WERE
IN PLACE OVER CENTRAL NORTH CAROLINA. THE JET ALOFT IS FORECAST BY
THE GFS AND NAM TO MOVE NORTHEAST AND OUT OF CENTRAL NORTH CAROLINA
DURING THE DAY...ALTHOUGH A FLAT RIDGE AXIS ALOFT WILL APPROACH THE
STATE TONIGHT WITH A GRADUAL INCREASE IN HIGH CLOUDS AND MAYBE EVEN
MORE MID-LEVEL CLOUDS IN THE 12000FT TO 15000FT RANGE OVERNIGHT
BASED ON THE MOISTURE PROFILES FROM BOTH THE NAM AND GFS BUFR
SOUNDINGS. K INDICES ARE NEGATIVE UNTIL LATE TONIGHT IN THE
INTERSTATE 85 CORRIDOR WHERE THE CLOUD BASES MAY BE A LITTLE LOWER
RELATIVE TO THE REST OF CENTRAL NORTH CAROLINA...BUT THE AIR MASS
BELOW 700MB REMAINS DRY AT LEAST THROUGH TONIGHT. THE CANADIAN CLOUD
COVER MODEL WHICH TENDS TO DO PRETTY WELL WITH THE ONSET AND
COVERAGE OF HIGHER CLOUDS INCREASES THE COVERAGE OF THOSE CLOUDS
GRADUALLY THIS AFTERNOON THROUGH TONIGHT WITH AREAS FROM KFAY TO
KRWI AND EAST TAKING LONGER TO GET AT LEAST BROKEN COVERAGE.

GFS BUFR SOUNDINGS ARE SLIGHTLY HIGHER THAN NAM BUFR SOUNDINGS WITH
REGARD TO THE POTENTIAL FOR A FEW WIND GUSTS IN THE TEENS KNOTS THIS
MORNING. BASED ON SOME STIRRING OF THE WINDS CONTINUING EARLY THIS
MORNING WILL LEAN TOWARD THE GFS AND ANTICIPATE A FEW WIND GUSTS IN
THE TEENS KNOTS THIS MORNING BEFORE ANY GUSTINESS SHOULD DIMINISH
INTO THE AFTERNOON AS THE SURFACE HIGH CONTINUES TO BUILD IN. WINDS
WILL BECOME LIGHT SOUTH TO SOUTHWEST BY THIS EVENING. UNDER GOOD
SUNSHINE...1000-850MB THICKNESSES AND A BLEND OF THE MAV AND MET MOS
GUIDANCE SUGGEST HIGHS FROM THE MID 40S TO LOWER 50S...HIGHEST
SOUTHWEST WHERE THE THICKNESSES WILL BE GREATER AND WINDS BECOME
WEST TO SOUTHWEST SOONER. TEMPERATURES SHOULD FALL SOMEWHAT QUICKLY
THIS EVENING THEN TEND TO STABILIZE AS CLOUDS MOVE IN. LOWS TONIGHT
25 TO 30 NEAR AND EAST OF INTERSTATE 95 AND AROUND 30 ELSEWHERE.
MINIMUM RELATIVE HUMIDITIES TODAY COULD FALL TO NEAR 15 PERCENT
BASED ON THE EXPECTED SURFACE DEW POINTS...BUT WINDS WILL BE MUCH
LIGHTER COMPARED TO FRIDAY AND BY THE TIME DEW POINTS WOULD FALL TO
THOSE LEVELS THE FREQUENCY OF ANY MODEST GUSTS SHOULD BE MUCH LOWER.
-- End Changed Discussion --

&&

.SHORT TERM /SUNDAY THROUGH MONDAY/...
-- Changed Discussion --
AS OF 335 PM FRIDAY...

HIGH PRESSURE WILL MOVE OFF THE EAST COAST SUNDAY... AS A LOW
PRESSURE SYSTEM MOVES INTO THE OHIO VALLEY. SOUTHWESTERLY LOW LEVEL
FLOW... AND INCREASING THICKNESSES WILL BRING HIGHS A FEW DEGREES
WARMER ON SUNDAY... AROUND 50. COLD FRONT WILL MOVE THROUGH THE AREA
ON MONDAY. A STRONG PRESSURE GRADIENT WILL DEVELOP AS THE LOW
DEEPENS OFF THE MIDATLANTIC COAST... AND HIGH PRESSURE BUILDS IN TO
THE MIDWEST... LEADING TO BREEZY CONDITIONS MONDAY AFTERNOON. STRONG
COLD ADVECTION WILL OVERTAKE THE REGION DURING THIS TIME... LEADING
TO A LIKELY NONDIURNAL TEMPERATURE TREND... WITH TEMPS FALLING
THROUGH THE 40S DURING THE DAY.
-- End Changed Discussion --

&&

.LONG TERM /MONDAY THROUGH THURSDAY/...
AS OF 309 PM FRIDAY...

HIGH PRESSURE WILL EXTEND ACROSS THE AREA TUESDAY AND WEDNESDAY...
AS ENERGY CURRENTLY OVER THE BAJA MOVES EASTWARD TO THE GULF COAST.
AN AREA OF LOW PRESSURE WILL DEVELOP IN RESPONSE OVER THE NORTHERN
GULF OF MEXICO ON WEDNESDAY... POTENTIALLY MOVING ALONG THE
SOUTHEAST COAST IN THE THURS/FRI TIMEFRAME. GFS REMAINS CLOSE TO THE
COAST WITH PRECIP MOVING IN LATER ON WEDNESDAY... 12Z ECMWF TAKES
THE LOW OUT TO SEA WITH LITTLE LOCAL IMPACT... AND GFS ENSEMBLE HAS
CONSIDERABLE VARIATION IN STRENGTH AND PROXIMITY TO THE COAST... SO
CONFIDENCE AT THIS TIME REMAINS LOW. TIMING WILL HAVE A GREAT IMPACT
ON PTYPE... WITH ANY OVERNIGHT PRECIP POTENTIALLY BRINGING PTYPE
ISSUES. AT THIS POINT... WILL CONTINUE WITH CHANCE OF RAIN UNTIL
TIMING/DEVELOPMENT CAN BE BETTER ASCERTAINED. TEMPERATURES WILL
CONTINUE TO BE BELOW NORMAL THROUGH THE END OF THE WEEK.

&&

.AVIATION /06Z SATURDAY THROUGH WEDNESDAY/...
-- Changed Discussion --
AS OF 115 AM SATURDAY...

VFR CONDITIONS CONTINUE FOR THE 06Z VALID TAF PERIOD. SATELLITE
IMAGES SHOW A FEW JET-STREAK CIRRUS IN CENTRAL NORTH CAROLINA EARLY
THIS MORNING...AND DURING THE DAY TODAY AND THROUGH THE OVERNIGHT
HOURS HIGH- AND MID-LEVEL CLOUDS WILL GRADUALLY MOVE IN FROM THE
WEST. EXPECT MORE OF THE MID-LEVEL CLOUDS TO APPEAR IN CENTRAL NORTH
CAROLINA TONIGHT...FROM AROUND 03Z AND LATER. FORECAST SOUNDINGS
ESPECIALLY FROM THE GFS SUGGEST A FEW WIND GUSTS INTO THE TEENS
KNOTS WITH INITIAL MIXING THIS MORNING...BUT THE TREND OF ANY
GUSTINESS SHOULD DIMINISH BY EARLY AFTERNOON AS THE SURFACE HIGH
CONTINUES TO BUILD IN. LIGHT SOUTH TO SOUTHWEST WIND BY THIS EVENING.

BEYOND THE 06Z VALID TAF PERIOD...SUB-VFR CONDITIONS AND AREAS OF
RAIN ARE LIKELY BY OVERNIGHT SUNDAY AHEAD OF A COLD FRONT THAT WILL
MOVE THROUGH CENTRAL NORTH CAROLINA EARLY MONDAY. AHEAD OF THE COLD
FRONT SUNDAY NIGHT...WINDS ALOFT WILL INCREASE TO SOUTHWEST AOA 50KT
BY 2500FT. VFR CONDITIONS RETURN BY MONDAY AFTERNOON WITH GUSTY WEST-
NORTHWEST AND NORTHWEST SURFACE WINDS. VFR CONDITIONS SHOULD THEN
CONTINUE THROUGH WEDNESDAY.
-- End Changed Discussion --

&&

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

&&

$$

SYNOPSIS...DJF
NEAR TERM...DJF
SHORT TERM...SEC
LONG TERM...SEC
AVIATION...DJF