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-- Discussion containing changed information from previous version are highlighted. --
000
FXUS62 KILM 130745
AFDILM

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE WILMINGTON NC
345 AM EDT SUN JUL 13 2014

.SYNOPSIS...
HIGH PRESSURE RIDGING WEST ACROSS THE AREA WILL BRING A SEASONABLE
AND MOSTLY DRY DAY TODAY...BEFORE HOT AND HUMID CONDITIONS DEVELOP
MONDAY AND TUESDAY. HEAT INDICES EARLY IN THE WEEK WILL EXCEED
100 DEGREES. A COLD FRONT WILL APPROACH LATE TUESDAY...AND THEN
STALL ACROSS THE AREA THROUGH THE UPCOMING WEEK. THIS WILL BRING
COOLER THAN NORMAL TEMPERATURES AND GOOD CHANCES FOR SHOWERS AND
THUNDERSTORMS EACH DAY.

&&

.NEAR TERM /THROUGH TONIGHT/...
AS OF 2 AM SUNDAY...LIGHT WINDS WILL BECOME CALM OVERNIGHT ALLOWING
SOME RADIATIONAL COOLING...ESPECIALLY INLAND. THIS WILL ALLOW TEMPS
TO DROP INTO THE UPPER 60S IN PLACES AS WELL AS INCREASE POTENTIAL
FOR FOG. BOUNDARY LAYER WINDS ARE FORECAST TO BE A LITTLE HIGHER
THAN LAST NIGHT AND DO NOT EXPECT WIDESPREAD VISIBILITIES BELOW 1SM.

ABUNDANT MID LEVEL DRY AIR AND SUBSIDENCE IN PLACE TODAY WILL KEEP
SKIES MOSTLY SUNNY AND SEVERELY LIMIT PRECIP CHANCES. PRECIPITABLE
WATER VALUES HANG AROUND 1.2 INCHES...WELL BELOW THE 1.75 INCHES
TYPICAL FOR MID JULY AND MID LEVEL LAPSE RATES ARE IN THE 5 TO 5.5
C/KM RANGE. CANNOT RULE OUT ISOLATED WEAK SHOWERS ALONG OR JUST
BEHIND THE SEA BREEZE...SIMILAR TO YESTERDAY...BUT MOST AREAS WILL
REMAIN DRY. ANY SHOWERS THAT DO DEVELOP WILL BE HARD PRESSED TO LAST
FOR AN EXTENDED PERIOD OF TIME GIVEN THE HARSH MID LEVEL
ENVIRONMENT.

HIGHS TODAY WILL AGAIN CLIMB INTO THE LOWER 90S AWAY FROM THE COAST.
SEA BREEZE SHOULD MAKE GOOD PROGRESS INLAND GIVEN THE SOUTH TO
SOUTHEAST SYNOPTIC FLOW. ALONG THE COAST EARLY SEA BREEZE
DEVELOPMENT WILL KEEP HIGHS IN THE MID TO UPPER 80S. LIGHT SOUTHERLY
FLOW OVERNIGHT WILL KEEP LOWS NEAR TO SLIGHTLY ABOVE CLIMO.

&&

.SHORT TERM /MONDAY THROUGH TUESDAY NIGHT/...
AS OF 330 AM SUNDAY...HOT AND HUMID WITH INCREASINGLY UNSETTLED
WEATHER WILL DEFINE THE SHORT TERM.

VERY UNCOMFORTABLE WEATHER EXPECTED BOTH DAYS FOR THE EARLY
WORK-WEEK PERIOD...AS RETURN FLOW PUMPS WARM MOIST AIR INTO THE
CAROLINAS...AND THE MUCH-DISCUSSED APPROACHING COLD FRONT GETS HUNG
UP WEST OF THE AREA UNTIL TUESDAY EVE. THIS LEAVES HIGH
THICKNESSES...850MB TEMPS OF 17-19C...AND DEW POINT TEMPS WELL INTO
THE 70S...BOTH MONDAY AND TUESDAY. TEMPS ON MONDAY WILL SOAR INTO
THE MID 90S EVERYWHERE EXCEPT THE IMMEDIATE BEACHES...AND WILL ONLY
BE A DEGREE OR SO COOLER ON TUESDAY. THIS REPRESENTS A
SEVERAL-DEGREE JUMP IN FORECAST HIGHS FOR TUESDAY...BUT GUIDANCE HAS
BACKED OFF ON THE LONGITUDINAL PROGRESSION OF THE COLD FRONT DURING
TUESDAY...SO A JUMP IS REQUIRED. THESE TEMPS WILL COMBINE WITH THE
HIGH DEWPOINTS...CAUSING HEAT INDICES TO APPROACH 105 ON
MONDAY...AND AROUND 100 ON TUESDAY. LOWS BOTH NIGHTS WILL BE
SIMILARLY WARM...MID/UPR 70S MONDAY NIGHT...AND A FEW DEGREES COOLER
ON TUESDAY.

WHILE HEAT WILL BE THE BIG CONCERN EARLY WEEK...CONVECTION WILL
BECOME INCREASINGLY WIDESPREAD INTO TUESDAY AHEAD OF THE ADVANCING
COLD FRONT. MONDAY WILL FEATURE ONLY ISOLATED STORMS...FOCUSED
PRIMARILY ON THE TYPICAL SEA BREEZE AND PIEDMONT TROUGH
BOUNDARIES...BUT LOWERING THICKNESSES AND THE COLD FRONT WILL CAUSE
MORE WIDESPREAD STORMS TUESDAY...AND ESPECIALLY TUESDAY NIGHT WHEN
COLUMN SATURATION OCCURS AND THE COLD FRONT REACHES THE ILM CWA.

&&

.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
AS OF 330 AM SUNDAY...COOL AND WET CONDITIONS ARE EXPECTED FOR THE
ENTIRETY OF THE LONG TERM AS A HIGHLY AMPLIFIED 500MB PATTERN DRIVES
AN ANOMALOUS TROUGH INTO THE EASTERN CONUS. BENEATH THIS TROUGH...A
COLD FRONT WILL PUSH INTO THE LOCAL AREA BY THE BEGINNING OF THE
EXTENDED...AND THEN STALL ACROSS THE EAST COAST. ALTHOUGH THIS
TROUGH IS QUITE STRONG...CAUSING LOWERED THICKNESSES ALL WAY TO NEAR
CUBA (!)...IT REMAINS POSITIVELY TILTED WITH AN AXIS FROM SW TO NE.
THIS IS UNFORTUNATE FOR THE LOCAL AREA SINCE THAT CAUSES FLOW TO
BECOME BOUNDARY PARALLEL...HENCE CAUSING THE FRONT TO STALL...PRETTY
MUCH OVERHEAD...INTO NEXT WEEKEND. AT THE SAME TIME...MOIST FLOW
FROM THE GULF OF MEXICO WILL REMAIN TAPPED AS THE SW FLOW ORIGINATES
FROM THAT AREA...AND THUS AN EXTENDED PERIOD OF WET WEATHER IS
ANTICIPATED. WPC HAS 2-4" OF QPF ACROSS THE AREA NEXT WEEK...AND
ALTHOUGH THERE IS SOME UNCERTAINTY INTO HOW MUCH THE FRONT WILL
WAVER INLAND/OFFSHORE...EXPECT THE MAJORITY OF THE PERIOD TO FEATURE
SLIGHTLY BELOW NORMAL TEMPS AND GOOD CHANCES FOR PRECIP.

&&

.AVIATION /08Z SUNDAY THROUGH THURSDAY/...
AS OF 06Z...EXPECT MVFR/TEMPO IFR VSBYS TO DEVELOP THIS MORNING AS
CONDITIONS REMAIN FAVORABLE FOR OVERNIGHT FOG. HIGHEST CONFIDENCE
FOR IFR VSBYS REMAINS AT KFLO/KLBT BETWEEN 09-12Z. THE COASTAL
TERMINALS WILL LIKELY SEE MVFR VSBYS BEFORE 12Z...BUT IFR CONFIDENCE
IS LOWER FOR THESE SITES...SO WILL NOT INCLUDE IT IN THE TAFS. THE
FOG SHOULD DISSIPATE SOON AFTER 12Z...AND THEN VFR WILL PREVAIL
THROUGH THE REST OF THE PERIOD. LIGHT SOUTHWEST WINDS AROUND 5 KTS
IN THE MORNING WILL BECOME SOUTH AROUND 10 KTS AFTER MIDDAY. COULD
SEE A STRAY AFTN SHOWER/TSTM ALONG THE SEA BREEZE...BUT WILL NOT
MENTION ANY VCSH ATTM AS COVERAGE WOULD BE VERY LIMITED.

EXTENDED OUTLOOK...INCREASING CHANCES FOR SHOWERS/TSTMS AND MVFR
CONDITIONS TUESDAY THROUGH THURSDAY AS A COLD FRONT STALLS OVER THE
CAROLINAS.

&&

.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 2 AM SUNDAY...WEAK GRADIENT AND RADIATIONAL COOLING INLAND MAY
ALLOW FOR LAND BREEZE DEVELOPMENT EARLY THIS MORNING. THIS WOULD
CAUSE W TO NW FLOW NEAR THE COAST WHILE WINDS ACROSS THE REMAINDER
OF THE WATERS WILL BE LIGHT AND FROM THE S-SW. WEAK GRADIENT AND
LARGE SCALE SOUTHERLY FLOW WILL ALLOW FOR DEVELOPMENT OF SEA BREEZE
BY EARLY AFTERNOON...ENHANCING ONSHORE FLOW NEAR THE COAST. WINDS
WILL BE 10 KT OR LESS AWAY FROM THE COAST AND 10 TO 15 KT NEAR
SHORE. SEAS WILL RUN 2 FT THROUGH THE AFTERNOON/EVENING. GRADIENT
BECOMES A LITTLE MORE DEFINED OVERNIGHT WITH SOUTHWEST FLOW
APPROACHING 15 KT. THIS WILL PUSH SEAS TO 3 FT BY THE END OF THE
PERIOD.

SHORT TERM /MONDAY THROUGH TUESDAY NIGHT/...
AS OF 330 AM SUNDAY...HIGH PRESSURE WELL OFFSHORE...AND A COLD FRONT
APPROACHING FROM THE WEST...WILL KEEP THE WATERS SANDWICHED IN
BETWEEN THROUGH THE PERIOD. THIS DRIVES A PINCHED GRADIENT...AND
FORCES SW WINDS TO INCREASE TO AROUND 20 KTS MUCH OF THE BEGINNING
OF THE WEEK. THESE STRONG WINDS WILL DRIVE WAVE HEIGHTS UP TO 3-5 FT
MUCH OF THE SHORT TERM...POSSIBLY REACHING 6 FT ON TUESDAY.
CAUTIONARY STATEMENTS ARE LIKELY FOR A PORTION OF THE EARLY-WEEK
TIME-FRAME...AND CONDITIONS NECESSITATING AN SCA MAY BE POSSIBLE.


LONG TERM /WEDNESDAY THROUGH THURSDAY/...
AS OF 330 AM SUNDAY...HIGH PRESSURE CENTERED WELL OFFSHORE WILL
GRADUALLY LOSE ITS INFLUENCE OVER THE WATERS AS A COLD FRONT STALLS
ACROSS THE AREA. AT THIS TIME EXPECT THE FRONT TO REMAIN JUST WEST
OF THE WATERS...BUT WILL HAVE THE EFFECT OF WEAKENING THE
GRADIENT...AND THUS SW WINDS WILL EASE FROM AROUND 15 KTS
WEDNESDAY...TO 10 KTS OR LESS ON THURSDAY. THIS WILL CAUSE WAVE
HEIGHTS TO SLOWLY FALL FROM 3-5 FT EARLY...TO 2-4 FT LATE
THURSDAY...EVEN AS A SE GROUND SWELL BEGINS TO AMPLIFY.

&&

.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...NONE.

&&

$$
SYNOPSIS...JDW
NEAR TERM...III
SHORT TERM...JDW
LONG TERM...JDW
AVIATION...III/BJR
MARINE...III/JDW