-- Discussion containing changed information from previous version are highlighted. --
000
FXUS62 KILM 291915
AFDILM

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE WILMINGTON NC
315 PM EDT TUE JUL 29 2014

.SYNOPSIS...
DRIER AND COOLER AIR WILL SETTLE INTO THE REGION AS CANADIAN HIGH
PRESSURE MIGRATES INTO THE AREA THIS WEEK. A COASTAL FRONT WILL
LIFT BACK NORTHWARD ACROSS OUR AREA THIS WEEKEND...BRINGING
INCREASED RAIN CHANCES FRIDAY THROUGH MONDAY.

&&

.NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/...
AS OF 3 PM TUESDAY...VAPOR ANIMATIONS SHOW THE BROAD UPPER TROUGH
CRADLED ACROSS THE EASTERN CONUS...WITH LITTLE OVERALL MOVEMENT
EXPECTED THROUGH TONIGHT AS AN UPPER LOW REMAINS QUASI-STATIONARY
ALONG THE VERY NORTHERN FRINGES OF THE GREAT LAKES. AT THE SURFACE
A WEAK LOW OFF OF CAPE FEAR WILL WEAKEN AS IT DRIFTS AWAY TO THE
NE ALLOWING BROAD HIGH PRESSURE TO SETTLE IN TO OUR N AND W. AS A
RESULT AN OVERALL LIGHT NE-ENE WIND FLOW IS EXPECTED FOR TONIGHT
UNDER CLEARING SKIES. THIS PROVIDES A GOOD RADIATIONAL COOLING
SET-UP AND WITH WET GROUND IN SOME AREAS...PATCHY DENSE GROUND
FOG MAY CROP OUT IN SPOTS EARLY ON WEDNESDAY.

MINIMUMS TONIGHT TO RUN 6-9 DEGREES BELOW NORMAL FOR JULY 30 BUT
RECORD LOWS WILL BE DIFFICULT TO CRACK AT SITES WITH EXTENSIVE
HISTORICAL CLIMATE RECORDS. HERE ARE A FEW OF THE LOCAL RECORDS
FOR JULY 30...ILM-61 LBT-67 FLO-63 MYR-69.

&&

.SHORT TERM /6 AM WEDNESDAY MORNING THROUGH THURSDAY NIGHT/...
AS OF 300 PM TUESDAY...A FLATTENED 500 MB TROUGH WILL REMAIN PARKED
OVER THE EASTERN U.S. ON WED...WHILE AT THE SURFACE BROAD HIGH
PRESSURE WILL BE POSITIONED TO OUR WEST. FORECAST SOUNDINGS REMAIN
FAIRLY DRY FOR WED...ESPECIALLY ABOVE ABOUT 700 MB. AS THE TROUGH
AXIS RETROGRADES A BIT ON THU...PWATS INCREASE IN THE AFTN HOURS
WITH THE MID LEVEL FLOW BECOMING MORE SOUTHWESTERLY. THE REMNANT
FRONT/SFC TROUGH OFFSHORE MAY ALSO DRIFT BACK TOWARD THE COAST LATE
THU...FURTHER MOISTENING THE COLUMN WITH INCREASING EASTERLY LOW
LEVEL WINDS. A FEW SPRINKLES CANNOT BE RULED OUT DURING THE DAY
WED...BUT WILL MAINTAIN INHERITED DRY FORECAST ATTM GIVEN THE LACK
OF A SEA BREEZE DUE TO WEAK LAND/SEA TEMP CONTRASTS. THU SEEMS LIKE
THE BETTER CANDIDATE FOR ISOLATED SHOWERS/TSTMS...ESPECIALLY LATE IN
THE PERIOD. HAVE SLOWLY RAMPED UP POPS THU AFTN INTO THE OVERNIGHT
HOURS...GENERALLY SLIGHT CHC WITH SOME CHC POPS ALONG THE COAST.

TEMPS WILL REMAIN BELOW NORMAL THANKS TO THE PERSISTENT UPPER TROUGH
AND EASTERLY SFC FLOW. HIGHS WILL BE IN THE MID TO UPPER 80S BOTH
DAYS. WED NIGHT LOWS WILL FALL INTO THE MID 60S INLAND AND UPPER 60S
ALONG THE COAST. INCREASING CLOUDS THU NIGHT WILL KEEP LOWS A FEW
DEGREES WARMER...GENERALLY UPPER 60S TO LOWER 70S.

&&

.LONG TERM /FRIDAY THROUGH TUESDAY/...
AS OF 3 PM TUESDAY...FRIDAY THROUGH SUNDAY FINALLY SEES THE DEEP
CUTOFF NORTH OF THE GREAT LAKES OPEN UP AND RETREAT. DEEP
TROUGHINESS LINGERS SOUTH OF THIS FEATURE HOWEVER AS THE FLOW SPLITS
WITH SOUTHERN BRANCH TROUGH COVERING MUCH OF THE OHIO AND MID/UPPER
MS VALLEY REGIONS. HERE IN THE CAROLINAS THIS LEADS TO A DEEP
MOISTURE-LADEN SOUTHWESTERLY FLOW THAT SHOULD LEAVE THE AREA PRONE
TO AT LEAST A CLIMATOLOGICAL SCATTERING OF DIURNAL CONVECTION.
DURING THIS SAME TIME FRAME A WARM FRONT WILL SLOWLY RETROGRADE FROM
A NEARLY COASTAL POSITION ON FRIDAY TO WEST OF THE AREA/CENTRAL
CAROLINAS BY SUNDAY. THIS WILL BOLSTER THE LL MOISTURE AND SHOULD
YIELD AND UPTICK IN CONVECTIVE COVERAGE AS THE WEEKEND TRANSPIRES.
THE SURFACE BOUNDARY BECOMES ILL-DEFINED IF NOT WASHED OUT
ALTOGETHER BY MONDAY. THIS COULD LEAD TO A SMALL DOWNWARD TREND IN
RAIN CHANCES...BUT WOULD LIKE TO BE CAUTIOUS WITH OPTIMISM AS THERE
WILL LIKELY BE OUTFLOW AND DIFFERENTIAL HEATING BOUNDARIES TO STILL
SERVE AS CONVECTIVE INITIATION FOCI. THE DEEP LAYER SWRLY FLOW WILL
ALSO BE WEAKENING. THE BETTER BET FOR A SLIGHTLY QUIETER FORECAST
COMES ON TUESDAY WHEN THE MID LEVEL TROUGHINESS NO LONGER HAS ANY
LOCAL EFFECTS AND THE FLOW VEERS TO MORE WESTERLY.

&&

.AVIATION /19Z TUESDAY THROUGH SUNDAY/...
AS OF 18Z...VFR WITH SCT/BKN LOW/MID LEVEL CLOUDS BECOMING SCT LATE
THIS AFTERNOON AND EVENING. A FEW LOW TOPPED SHOWERS MAY DEVELOP
THIS AFTERNOON BUT WILL LEAVE OUT OF TAFS DUE TO THE ISOLATED NATURE
OF THE ACTIVITY. WINDS WILL BE LIGHT NW-NE EXCEPT BECOMING E-SE BY
MID AFTERNOON AT THE COASTAL TERMINALS.

VFR THIS EVENING THROUGH THE END OF THE TAF VALID PERIOD. WINDS WILL
BE LGT/VRBL OVERNIGHT BECOMING LIGHT E TOMORROW MORNING.

EXTENDED OUTLOOK...MVFR VSBYS DUE TO MORNING FOG FRIDAY AND
SATURDAY...OTHERWISE VFR. CHANCE MAINLY AFTN/EVNG SHRA/ISOLATED
TSRA THROUGH THE PERIOD.

&&

.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 3 PM WEDNESDAY...SEAS OF 2-3 FEET CAN BE EXPECTED THROUGH
THE AFTERNOON AND OVERNIGHT...MAINLY IN DOMINANT WAVE PERIODS
AROUND 7 SECONDS FROM THE ESE. A LIGHT NE-E CHOP WILL ACCOMPANY
THESE SE WAVES AND SINCE WILL REMAIN LIGHT...SO WILL THE CHOP.
WINDS 10 KT OR LESS RANGING FROM NNE-ENE THROUGH EARLY WEDNESDAY.
NO TSTMS OR RESTRICTIONS TO VSBY EXPECTED ON THE 0-20NM WATERS
TONIGHT INTO SUNRISE WEDNESDAY...ONLY PATCHY GROUND FOG NEAR THE
ICW IN A FEW LOCATIONS.

SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/...
AS OF 300 PM TUESDAY...NORTHEAST TO EAST WINDS AROUND 10 KTS WILL
PREVAIL THROUGH THE PERIOD AS SFC HIGH PRESSURE TO OUR NORTHWEST
GRADUALLY MOVES OFFSHORE DURING THU. SEAS WILL REMAIN IN THE 2-3 FT
RANGE BOTH DAYS...HIGHEST ACROSS AMZ250 WHERE SEAS WILL BECOME AROUND
3 FT ON THU. AS THE REMNANT FRONT/SFC TROUGH OFFSHORE LIFTS BACK
TOWARD THE COAST...SHOWER/TSTM CHANCES OVER THE WATERS INCREASE
OVERNIGHT THU.

LONG TERM /FRIDAY THROUGH SUNDAY/...
AS OF 3 PM TUESDAY...WITH A BOUNDARY STALLED VERY CLOSE TO IF NOT
RIGHT OVER THE COAST ON FRIDAY THE WATERS WILL EXPERIENCE A LIGHT
ONSHORE FLOW. ONSHORE WINDS ACT TO LESSEN THE GRADIENT IN WAVE
HEIGHT ACROSS THE 20NM WIDTH OF THE FORECAST ZONES SO A GENERAL 3 FT
SEA STATE EXPECTED...A COMBINATION OF THE WIND WAVE AND A LIGHT
SOUTHEASTERLY SWELL. OVER THE WEEKEND THE BOUNDARY WILL SLOWLY DRAW
INLAND...REACHING THE CENTRAL CAROLINAS BY SUNDAY. THE ONLY REAL
LOCAL EFFECT WILL BE A VEERING TO SE OR EVEN S AT TIMES. LAND/SEA
TEMPERATURE DIFFERENCES WILL BE MINIMAL FOR THE TIME OF YEAR AND NO
APPRECIABLE SEA BREEZE EXPECTED TO PRODUCE THE NORMAL NEARSHORE WIND
INCREASE AND CHOP.

&&

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

&&

$$

NEAR TERM...MJC
SHORT TERM...BJR
LONG TERM...MBB
AVIATION...MRR/MJC
MARINE...MJC/MBB/BJR