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-- Discussion containing changed information from previous version are highlighted. --
000
FXUS62 KILM 121116
AFDILM

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE WILMINGTON NC
716 AM EDT SAT JUL 12 2014

.SYNOPSIS...
WEAK SURFACE FRONT WILL DISSIPATE OFFSHORE TODAY...WITH DRIER HIGH
PRESSURE SETTLING OVER THE AREA THROUGH SUNDAY. HOT TEMPERATURES
ARE EXPECTED MONDAY...AHEAD OF A COLD FRONT WHICH WILL STALL
ACROSS THE AREA TUESDAY THROUGH THE END OF NEXT WEEK. THIS FRONT
WILL BRING COOLER TEMPERATURES AND GOOD CHANCES FOR SHOWERS AND
THUNDERSTORMS.

&&

.NEAR TERM /THROUGH TONIGHT/...
AS OF 7 AM SATURDAY...HAVE RAISED A DENSE FOG ADVISORY FOR INLAND
COUNTIES GIVEN REPORTS OF VISIBILITY LESS THAN 1/4 MILE AND
SATELLITE IMAGERY SHOWING PATCHES OF FOG. ADVISORY RUNS THROUGH 9
AM AT WHICH POINT ALL FOG SHOULD HAVE BURNED OFF.

ISOLATED SHOWERS HAVE DEVELOPED IN THE VICINITY OF SEVERAL REMNANT
BOUNDARIES...MAINLY IMPACTING BRUNSWICK AND HORRY COUNTIES. SOME
OF THESE HAVE POPPED UP ALONG THE DECAYING SURFACE BOUNDARY THAT
IS SLOWLY MOVING SOUTH ACROSS THE AREA. SOME OF THE ACTIVITY ALSO
APPEARS TO BE ASSOCIATED WITH A WEAK LAND BREEZE AND A REMNANT
OUTFLOW BOUNDARY FROM CONVECTION OFF THE HORRY COUNTY COAST LAST
EVENING. WATER VAPOR SHOWS A SIGNIFICANT AMOUNT OF DRY AIR
SPREADING OVER THE FORECAST AREA THIS MORNING. THE ARRIVAL OF THIS
DEEPER DRY AIR AND SUNRISE SHOULD INDUCE A WEAKENING TREND DURING
THE NEXT FEW HOURS AND ACTIVITY OVER LAND SHOULD BE
ENDING/OFFSHORE BY MID MORNING. OTHER THAN ADJUSTMENTS TO POP/WX
GRIDS/FORECAST HAVE NOT MADE ANY SIGNIFICANT CHANGES.

PREVIOUS DISCUSSION FOLLOWS:
AS OF 2 AM SATURDAY...WEAK SURFACE BOUNDARY MOVING INTO THE AREA
WILL PUSH OFF THE COAST LATER THIS MORNING. LIGHT TO CALM WINDS
ASSOCIATED WITH ILL DEFINED PRESSURE PATTERN AND ABUNDANT LOW
LEVEL MOISTURE WILL LEAD TO FOG DEVELOPMENT OVERNIGHT. FOG WILL BE
MORE WIDESPREAD INLAND BUT OVERALL IMPACT ON VISIBILITY SHOULD BE
LIMITED AS DRY AIR SLOWLY FILTERS IN BEHIND THE BOUNDARY.

WHAT REMAINS OF THE SURFACE BOUNDARY TODAY WILL LINGER ALONG OR JUST
OFF THE COAST. AFTERNOON CONVECTION WILL BE POSSIBLE...ESPECIALLY
ALONG THE COAST BUT THE MID LEVEL ENVIRONMENT WILL BE MUCH DIFFERENT
FROM PAST DAYS. EASTWARD EXPANSION OF MID LEVEL RIDGE WILL INCREASE
SUBSIDENCE ACROSS THE FORECAST AREA...DRYING OUT THE MID LEVELS.
HEIGHT RISES AND INCREASED SUNSHINE WILL PUSH HIGHS INTO THE 90S
AWAY FROM THE COAST. DESPITE WARMER TEMPS THE LOW LEVEL DRY AIR
COMBINED WITH SUBSIDENCE/MID LEVEL DRYING WILL LIMIT COVERAGE OF
AFTERNOON CONVECTION TO AT MOST 20% OR SO. BEST CHANCES WILL BE
ALONG THE SEA BREEZE AS IT FIRST DEVELOPS AND THEN STARTS TO PUSH
INLAND. FARTHER INLAND SEA BREEZE CONVECTION WILL HAVE A HARDER
TIME SUSTAINING AS IT MOVES INTO STRONGER MID LEVEL SUBSIDENCE.

ANY LINGERING CONVECTIVE DEBRIS FROM AFTERNOON ACTIVITY WILL QUICKLY
DISSIPATE THIS EVENING LEAVING CLEAR SKIES OVERNIGHT. BOUNDARY LAYER
WINDS UNDER 5 KT ALONG WITH CLEAR SKIES WILL LEAD TO CONDITIONS
IDEAL FOR FOG DEVELOPMENT AS WELL AS LOWS A LITTLE BELOW CLIMO.

&&

.SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/...
AS OF 300 AM SATURDAY...INCREASING HEAT AND HUMIDITY DURING THE
SHORT TERM...BUT OVERALL A DRIER AND SUNNIER FEW DAYS THAN WE HAVE
EXPERIENCED RECENTLY. WHILE THE 500MB FLOW BEGINS TO TREND TOWARDS
ONE OF HIGH-AMPLIFICATION...THIS WILL NOT OCCUR LOCALLY UNTIL THE
END OF THE PERIOD...AND THUS RIDGING ALOFT COMBINED WITH RETURN FLOW
AROUND OFFSHORE HIGH PRESSURE WILL CREATE A NICE FEW DAYS ACROSS THE
ILM CWA. SUNDAY WILL BE THE DRIER OF THE TWO...AS EXCEEDINGLY DRY
MID-LEVEL AIR HELPS KEEP PWATS AROUND 1.25 INCHES...AND EXPECT ONLY
AN ISOLATED SHOWER OR TSTM DURING THE AFTN. HOWEVER...WOULD NOT BE
SURPRISED IF THE AREA REMAINS DRY DURING SUNDAY. CONTINUED RETURN
FLOW AND THE BEGINNING OF SUBTLE HEIGHT FALLS ALOFT WILL CAUSE
INCREASING POP CHANCES FOR MONDAY...BUT STILL EXPECT ONLY TYPICAL
SUMMERTIME CONVECTION. VERY LATE MONDAY A COLD FRONT WILL APPROACH
AND THUS PRECIP MAY BEGIN TO INCREASE ONCE AGAIN AT THE END OF THE
PERIOD...BUT OTHERWISE MUCH OF MONDAY WILL FEATURE TYPICAL CAROLINA
SUMMERTIME WEATHER.

TEMPS SUNDAY WILL RISE INTO THE MID 90S WELL INLAND...WITH 90 DEGREE
HIGHS EXPECTED EVERYWHERE EXCEPT ON THE BEACHES. MONDAY WILL FEATURE
MAXIMUMS A DEGREE OR TWO WARMER AS THE LOW-LEVEL THERMAL RIDGE
INCREASES AHEAD OF THE ADVANCING COLD FRONT. MINS BOTH NIGHTS WILL
BE HELD ABOVE NORMAL THANKS TO WARM SOUTHERLY FLOW...BUT WHILE
SUNDAY NIGHT WILL DROP INTO THE LOW 70S...MONDAY NIGHTS LOWS WILL
LIKELY STAY IN THE UPPER 70S EXCEPT WELL INLAND.

&&

.LONG TERM /TUESDAY THROUGH FRIDAY/...
AS OF 300 AM SATURDAY...VERY STRONG UPPER TROUGH WILL LOAD ACROSS
CANADA AND DROP ACROSS THE EASTERN CONUS...IN A PATTERN THAT IS
QUITE ATYPICAL FOR MID-JULY. GUIDANCE REMAINS IN VERY GOOD AGREEMENT
THAT THIS TROUGH...PROGGED TO BE NEAR -3 SD`S IN INTENSITY...WILL
DROP INTO THE GREAT LAKES TUESDAY BEFORE SLOWLY ROTATING OFF TO THE
NORTHEAST THROUGH LATE WEEK. WHILE THIS WILL KEEP THE TROUGH
POSITIVELY TILTED AND THUS MAINTAIN RELATIVELY HIGHER THICKNESSES
LOCALLY...TEMPS ARE STILL EXPECTED TO BE BELOW NORMAL THROUGH THE
PERIOD...POSSIBLY WELL BELOW BY THURSDAY. AT THE SURFACE...A COLD
FRONT WILL APPROACH VERY EARLY TUESDAY AND THEN STALL IN THE
VICINITY THROUGH THURSDAY. THIS WILL CREATE AN EXTENDED PERIOD OF
HIGH POP WITH VERY UNSETTLED CONDITIONS LIKELY. WHILE SPC IS
HIGHLIGHTING THE REGION JUST NORTH OF HERE FOR SEVERE WEATHER
POTENTIAL...THERE IS AT LEAST SOME RISK ON TUESDAY AS THE FRONT
CROSSES INTO THE CWA...DUE TO THE VERY SIGNIFICANT AIR MASS
DIFFERENCES. THURSDAY MAY BE A BIT DRIER AS SOME MID-LEVEL DRY AIR
BUILDS IN BEHIND THE FRONT...BUT THIS WILL BE SHORT LIVED AS A WAVE
OF LOW PRESSURE IS PROGGED TO DEVELOP ON THE FRONT BY FRIDAY...ONCE
AGAIN INCREASING RAIN CHANCES FOR THE END OF THE WEEK.

&&

.AVIATION /11Z SATURDAY THROUGH WEDNESDAY/...
AS OF 12Z...LITTLE BIT OF CONVECTION ALONG THE COAST THIS
MORNING...AHEAD OF MUCH DRIER AIR PUNCHING INTO THE REGION. INLAND
TERMINALS MAY EXPERIENCE SOME BRIEF DENSE FOG...BUT MOST OF IT WILL
MIX OUT IN AN HOUR OR SO. VERY LIGHT GRADIENT TODAY...MAINLY AN
EASTERLY COMPONENT SHIFTING TO THE SOUTHEAST THIS AFTERNOON WITH THE
SEA BREEZE. THERE PROBABLY WILL NOT BE ANY CONVECTION THIS AFTERNOON
GIVEN THE DRY AIR ALOFT...WORST CASE ISOLATED ACTIVITY ALONG THE
RESULTANT BOUNDARY. LIGHT WINDS TONIGHT WITH LITTLE OR NO FOG
EXPECTED.

EXTENDED OUTLOOK...MVFR/IFR VSBYS POSSIBLE SUNDAY MORNING. OTHERWISE
MAINLY VFR CONDITIONS EXPECTED THROUGH MONDAY. INCREASING CHANCES
FOR SHOWERS/TSTMS TUESDAY AND WEDNESDAY.

&&

.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 7 AM SATURDAY...ISOLATED CONVECTION OVER THE WATERS THIS
MORNING IS DEVELOPING ALONG THE WEAKENING SURFACE BOUNDARY
DROPPING SOUTH ACROSS THE AREA AND REMNANT CONVECTIVE BOUNDARIES.
ACTIVITY HAD BEEN SLOW MOVING BUT LAST FEW SCANS OF KLTX RADAR
SHOW PRONOUNCED SOUTHEASTWARD ACCELERATION. SURFACE BOUNDARY
MOVING SOUTH ACROSS THE AREA AND ARRIVAL OF MID LEVEL DRY AIR
ARE PUSHING THIS ACTIVITY SOUTH. WINDS OUTSIDE CONVECTION WILL
REMAIN LIGHT AND VARIABLE WITH SEAS 1 TO 2 FT.

PREVIOUS DISCUSSION FOLLOWS:
AS OF 2 AM SATURDAY...REMAINS OF A SURFACE BOUNDARY MOVING INTO
THE AREA TODAY WILL DISSIPATE BY AFTERNOON AS SEA BREEZE DEVELOPS
AND BECOMES MORE DOMINANT. GRADIENT WILL REMAIN WEAK THROUGH THE
PERIOD WITH HIGHEST WINDS BEING DRIVEN BY THE SEA BREEZE. EARLY IN
THE PERIOD WINDS WILL BE LIGHT FROM THE NORTHEAST BUT DEVELOPMENT
OF SEA BREEZE WILL VEER TO WINDS TO SOUTHEAST. SPEEDS MUCH ABOVE
10 KT ARE NOT EXPECTED...EVEN NEAR SHORE. SEAS 1 TO 2 FT THIS
MORNING WILL TRANSITION TO 2 FT WITH DEVELOPMENT OF ONSHORE FLOW.

SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/...
AS OF 300 AM SATURDAY...SOUTHERLY WINDS ON SUNDAY WILL VEER TO
BECOME SW ON MONDAY AS HIGH PRESSURE OFFSHORE BECOMES THE DOMINANT
SYNOPTIC FEATURE. WHILE WINDS ON SUNDAY WILL BE ONLY AROUND 10
KTS...THE GRADIENT WILL BEGIN TO TIGHTEN CONSIDERABLY ON MONDAY AS A
COLD FRONT APPROACHES FROM THE NW. THIS WILL DRIVE WINDS UP TO 20
KTS MONDAY...HIGHEST LATE IN THE DAY. SEAS INITIALLY WILL BE AROUND
2 FT...BUT AS WINDS VEER TO THE SW AND INCREASE LATE SUNDAY...AND
ESPECIALLY MONDAY...WAVE HEIGHTS WILL BUILD TO 4-5 FT...AND
CAUTIONARY STATEMENTS MAY BE REQUIRED ON MONDAY.

LONG TERM /TUESDAY THROUGH WEDNESDAY/...
AS OF 300 AM SATURDAY...POTENT COLD FRONT WILL STALL JUST INLAND
FROM THE WATERS THROUGH MID-WEEK...WHILE HIGH PRESSURE REMAINS
CENTERED WELL OFFSHORE. THIS WILL CREATE A PINCHED GRADIENT THROUGH
THE EXTENDED...WITH SW WINDS OF 15-20 KTS REMAINING MOSTLY UNCHANGED
BOTH DAYS. THESE WINDS WILL DRIVE WAVE HEIGHTS TO 3-5 FT TUESDAY AND
INTO WEDNESDAY...BEFORE WINDS EASE A BIT AND SEAS FALL TO 2-4 FT
LATE.

&&

.ILM WATCHES/WARNINGS/ADVISORIES...
SC...DENSE FOG ADVISORY UNTIL 9 AM EDT THIS MORNING FOR SCZ017-023-
     024-032-033.

NC...DENSE FOG ADVISORY UNTIL 9 AM EDT THIS MORNING FOR NCZ087-096.

MARINE...NONE.

&&

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