000
FXUS62 KMHX 181038
AFDMHX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NEWPORT/MOREHEAD CITY NC
638 AM EDT TUE JUN 18 2013

.SYNOPSIS...
SEVERAL AREAS OF LOW PRESSURE WILL MOVE ALONG A STALLED FRONTAL
BOUNDARY BISECTING NORTH CAROLINA TUESDAY AND WEDNESDAY. WEAK HIGH
PRESSURE WILL BUILD IN FROM THE NORTH THROUGH THE END OF THE WEEK
WITH THE FRONTAL BOUNDARY STALLED SOUTH AND EAST OF THE REGION.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
AS OF 630 AM TUESDAY...MOST OF THE SHOWER ACTIVITY IS NOW ALONG
THE IMMEDIATE COAST. MADE MINOR POP ADJUSTMENTS FOR EARLY THIS
MORNING TO REFLECT BEST CHANCE ALONG THE COAST IN CARTERET COUNTY
TOWARDS OCRACOKE FOR THE NEXT FEW HOURS. EXPECT ADDITIONAL
SHOWERS AND THUNDERSTORMS TO DEVELOP WITH DAYTIME HEATING IN THE
VICINITY OF A WEAK FRONTAL BOUNDARY. PRECIPITABLE WATER VALUES ARE
RUNNING EXTREMELY HIGH...AT OR EVEN ABOVE TWO INCHES TODAY. ANY
SHOWERS AND THUNDERSTORMS THAT DO DEVELOP WILL BRING VERY HEAVY
DOWNPOURS AND SOME AREAS COULD SEE POOR DRAINAGE FLOODING. MODELS
AGREE ON THE GENERAL WET TREND...BUT THERE ARE SIGNIFICANT
DIFFERENCES ON TIMING AND LOCATION OF THE BEST CHANCE OF RAIN.
EXPECT THE HIGHEST CHANCE OF RAIN TO COME TONIGHT. FOR TEMPS
FOLLOWED CLOSE TO ECMWF GUIDANCE TODAY...WHICH WAS A MIDDLE GROUND
BETWEEN COOLER NAM AND WARMER GFS GUIDANCE. THIS WAS SIMILAR TO
THE PREVIOUS FORECAST WITH HIGHS IN THE MID 80S.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM WEDNESDAY/...
AS OF 400 PM TUESDAY...AS MENTIONED IN THE NEAR TERM DISCUSSION
THERE ARE TIMING AND LOCATION DIFFERENCES FOR THE AREAS OF HIGHEST
POP AND QPF BETWEEN THE MODELS. NOT ENOUGH CONFIDENCE TO FAVOR ONE
SOLUTION OVER THE OTHER...SO WENT WITH LIKELY POPS FOR THE
OVERNIGHT ALL LOCATIONS. HEAVY CLOUDCOVER AND A CONTINUED SW
BREEZE WILL AGAIN KEEP IT WARM AND MUGGY TONIGHT WITH LOWS AGAIN
IN THE 70 TO 75 RANGE MOST LOCATIONS. HIGH PRECIPITABLE WATER
CONDITIONS CONTINUE OVERNIGHT...BRINGING A CHANCE OF TORRENTIAL
DOWNPOURS AND MINOR POOR DRAINAGE FLOODING WHERE THE HEAVIEST
BANDS OF SHOWERS AND ISOLATED THUNDERSTORMS SET UP.

&&

.LONG TERM /WEDNESDAY THROUGH MONDAY/...
AS OF 300 PM MON...BROAD TROUGHING GRADUALLY AMPLIFIES ACROSS THE
GREAT LAKES AND NORTHEAST EARLY NEXT WEEK WITH A SERIES OF
SHORTWAVE TROUGHS MOVING THROUGH THE FLOW ALOFT. MODELS ARE COMING
INTO BETTER AGREEMENT WITH A BACKDOOR COLD FRONT PUSHING SLOWLY
SOUTH ACROSS THE REGION WED AND A STRONGER SHORTWAVE MOVING
THROUGH THE FLOW ALOFT WHICH AIDS IN DEVELOPING A WEAK AREA OF LOW
PRES ALONG THE FRONT. STRONGER UPPER LEVEL SUPPORT AND SFC
CONVERGENCE ALONG THE FRONT WILL MAINTAIN DESCENT PRECIP CHANCES
THROUGH MUCH OF WED AND MAINTAIN HIGH CHANCE TO LIKELY POPS.
PWATS INCREASE TO AROUND 2 INCHES WHICH COULD BRING PERIODS OF
HEAVY RAIN TUES INTO WED AS WELL. THE FRONT WILL STALL SOUTH OF
THE REGION THU AND FRI WITH DRIER CONDITIONS EXPECTED BUT COULD
SEE ISOLATED TO SCATTERED SHOWERS ACROSS SOUTHERN SECTIONS
DEPENDING ON JUST HOW FAR SOUTH THE FRONT STALLS. THE LATEST TWO
RUNS OF ECMWF INDICATE AN INVERTED TROUGH OFF THE CAROLINA COAST
THURS AND FRI. THE PROXIMITY OF THIS FEATURE WILL DETERMINE THE
CHANCES FOR PRECIP AND FOR NOW HAVE HEDGED CLOSER TO THE ECMWF
WHICH KEEPS THE TROUGH CLOSE ENOUGH FOR WEAK SHOWERS/THUNDERSTORMS
ALTHOUGH THE 12Z GFS NOSES THE SURFACE RIDGE FAR ENOUGH SOUTH TO
KEEP THE TROUGH WELL OFF THE COAST. THE BROAD UPPER TOUGH LIFTS
OUT FOR THE WEEKEND WITH RIDGING BUILDING IN FROM THE WEST.
GREATER DISAGREEMENT BUILDS ON SAT/SUN AS THE 12Z GFS REMAINS DRY
ACROSS THE CWA WHILE THE 00Z ECMWF BRING THE COASTAL TROUGH INTO
THE AREA WHICH COULD INCREASE SHOWER CHANCES THROUGH THE WEEKEND.
TRIED TO PICK A MIDDLE ROAD AND HIGHLIGHT ONLY THE SOUTHERN
COASTAL COUNTIES FOR PRECIP CHANCES THIS WEEKEND WITH GREATER POPS
DURING THE AFTERNOON WHERE DIURNAL/SEA-BREEZE CONVECTION IS
POSSIBLE.

TEMPS WILL BE NEAR CLIMO WED WITH HIGHS IN THE MID 80S WITH
CLOUDS AND PRECIP EXPECTED. NE-E FLOW ACROSS THE REGION THUR AND
FRI WILL KEEP TEMPS A FEW DEGREES BELOW CLIMO...IN THE LOW TO MID
80S. SURFACE RIDGE WILL SHIFT OFF THE MID-ATLANTIC COAST SAT WITH
WINDS SHIFTING SE THROUGH THE WEEKEND AND TEMPS GRADUAL WARMING
BACK INTO THE MID/UPPER 80S. SHOULD THE INVERTED TROUGH INDICATED
BY THE ECMWF COME TO FRUITION...TEMPS COULD BE A FEW DEGREES BELOW
CLIMO THIS WEEKEND.

&&

.AVIATION /12Z TUESDAY THROUGH SATURDAY/...
SHORT TERM /THROUGH TUESDAY/...
AS OF 130 AM TUESDAY...THERE WILL BE A FEW AREAS OF LOW STRATUS
ASSOCIATED WITH WEKENING SHOWERS IN THE NEXT FEW HOURS ACROSS THE
AREA THAT WILL BRING A BRIEF PERIOD OF MVFR CONDITIONS. WILL SEE A
BREAK IN THE SHOWER ACTIVITY INTO THE MORNING WITH CHANCES
INCREASING IN THE AFTERNOON AND INTO THE EVENING FOR MORE SHOWERS
AND TSTMS AND POSSIBLE MVFR CONDITIONS. VERY DIFFICULT TO DISCERN
ANY TIMING AT THIS POINT WITH QUITE A SPREAD IN MODEL SOLUTIONS
REGARDING THAT.

LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
AS OF 300 PM MON...A BROAD UPPER TROUGH AND ASSOCIATED FRONTAL
BOUNDARY WILL APPROACH TUES NIGHT WITH THE FRONTAL BOUNDARY
PROGGED TO PUSH THROUGH THE REGION WED. MOISTURE AND INSTABILITY
INCREASE TUES AND COULD SEE SHOWERS AND THUNDERSTORMS REDUCE
CIGS/VSBYS TUES THROUGH WED. THE FRONT STALL WILL SOUTH OF THE
REGION LATE WED INTO THURS WITH BEST SHOWER/TSTM CHANCES ACROSS
SOUTHERN AREAS...BEST CHANCES AT OAJ/EWN. HIGH PRESSURE BUILDS
SOUTH OVER THE TERMINALS BY LATE WEEK WITH VFR CONDITIONS
DOMINATING.

&&

.MARINE...
SHORT TERM /THROUGH TUESDAY/...
AS OF 630 AM TUESDAY...NO CHANGES THIS UPDATE. PRETTY GOOD MODEL
AGREEMENT ON THE WIND FORECAST TODAY AND TONIGHT. A MODERATE SW
BREEZE OF 10 TO 20 KT WILL PREVAIL THROUGH THE PERIOD. THE
PERSISTENT FLOW OFFSHORE WILL RESULT IN SEAS BUILDING THIS EVENING
AND TONIGHT TO 6 FEET FROM OREGON INLET SOUTHWARD. FAVORED LOCAL
NEARSHORE WAVE PREDICTION SYSTEM SEAS OVER WAVEWATCH 3...WHICH
DELAYED THE ONSET AND MAGNITUDE OF SEAS SLIGHTLY. RAISED A SMALL
CRAFT ADVISORY FOR TONIGHT THIS FORECAST UPDATE.

LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
AS OF 130 AM TUESDAY...NO SIGNIFICANT CHANGES THIS UPDATE. THE
BERMUDA HIGH WILL PUSH FARTHER OFFSHORE TUES NIGHT INTO WED. SW
GRADIENT TIGHTENS SLIGHTLY WED ACROSS THE SOUTHERN WATERS AHEAD OF
A BACKDOOR COLD FRONT BRINGING SW WINDS AROUND 15-20 KT WITH
HIGHER GUSTS WHILE NORTHERN WATERS ARE EXPECTED TO REMAIN BELOW 15
KT. COULD SEE MINIMAL SCA CONDITIONS DEVELOP WITH LOCAL SWAN
SLIGHTLY HIGHER THAN 12Z WAVEWATCH III...INDICATING 6 FT SEAS
ACROSS THE OUTER PORTIONS OF THE SOUTHERN OUTER WATERS. THE FRONT
THEN SLOWLY PUSHES THROUGH THE WATERS WED/WED NIGHT AND STALLS TO
THE SOUTH WITH WINDS SHIFTING TO NE THROUGH THE END OF THE WEEK.
MODELS VARY ON WIND SPEEDS THURS INTO EARLY FRI BASED ON THE
STRENGTH OF SEVERAL AREAS OF LOW PRES PROGGED TO DEVELOP ALONG THE
FRONT BUT GENERALLY EXPECT WINDS AROUND 10-20 KT WITH SEAS AROUND
3-5 FT. AN INVERTED TROUGH WILL DEVELOP OFF THE CAROLINA COAST
THURS AND FRI...BUT UNCERTAINTY REMAINS AS TO HOW CLOSE TO THE
COAST THIS FEATURE WILL RESIDE AND THUS THERE IS GREATER
UNCERTAINTY IN THE WIND/SEAS FORECAST FOR LATE WEEK INTO SAT.
CURRENTLY EXPECT WINDS SHIFTING E SAT WITH SEAS 2-4 FT.

&&

.MHX WATCHES/WARNINGS/ADVISORIES...
NC...NONE.
MARINE...SMALL CRAFT ADVISORY FROM 8 PM THIS EVENING TO 6 AM EDT
     THURSDAY FOR AMZ152-154.
     SMALL CRAFT ADVISORY FROM 2 AM TO 4 PM EDT WEDNESDAY FOR
     AMZ156-158.

&&

$$
SYNOPSIS...RSB
NEAR TERM...RSB
SHORT TERM...RSB
LONG TERM...SK
AVIATION...RSB/SK
MARINE...RSB/SK