Area Forecast Discussion Issued by NWS Newport/Morehead, NC
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000
FXUS62 KMHX 172249
AFDMHX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NEWPORT/MOREHEAD CITY NC
649 PM EDT MON JUN 17 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 /TONIGHT/...
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AS OF 645 PM MONDAY...LATEST SFC ANALYSIS SHOWS HIGH PRESSURE
OFFSHORE WITH TROUGHING INTO WESTERN/CENTRAL NC. JUST TWEAKED
GRIDS SLIGHTLY FOR EARLY PM UPDATE BASED ON LATEST TRENDS. LATEST
RADAR IMAGERY SHOWS LINE OF SHOWERS AND THUNDERSTORMS WITH HEAVY
RAIN EXTENDING FROM THE NORTHERN OUTER BANKS TO KINSTON. AT THIS
TIME STILL THINK SVR THREAT REMAINS LOW...WITH THE MAIN THREAT
BEING HEAVY RAINFALL. PWAT VALUES AROUND 2" AND STORM MOTION LESS
THAN 10KT IS RESULTING IN CELL TRAINING. RADAR ESTIMATES THAT
AREAS IN SOUTHERN WASHINGTON/TYRRELL COUNTIES HAVE SEEN
5-6"...SOUTH OF CRESWELL AND NEAR PHELPS LAKE. SCT SHOWERS AND ISO
THUNDERSTORMS WILL LIKELY CONTINUE OVERNIGHT...AS ACTIVITY
CONTINUES BACK TO THE SW. WILL CONTINUE HIGH CHANCE/LIKELY POPS
EARLY...TAPERING BACK TO CHANCE LATE TONIGHT...GIVEN A MOIST
BOUNDARY LAYER AND SOME WEAK MID-LEVEL ENERGY. ANOTHER WARM/MUGGY
NIGHT UPCOMING WITH LOWS IN THE LOWER AND MIDDLE 70S.-- End Changed Discussion --
&&
.SHORT TERM /TUESDAY/...
AS OF 310 PM MONDAY...A SERIES OF SURFACE LOWS WILL TRACK FROM
WEST TO EAST ALONG A STALLED FRONTAL BOUNDARY THAT WILL BE
BISECTING THE STATE ON TUESDAY. DEEP MOISTURE COUPLED WITH SURFACE
CONVERGENCE ALONG THE FRONT AND WEAK MID-LEVEL ENERGY WILL MAKE
FOR HIGH CHANCE POPS THROUGH THE DAY TUESDAY FOR ALL BUT THE OUTER
BANKS. PRECIPITABLE WATER VALUES OF GREATER THAN 2 INCHES WILL
LEAD TO A THREAT OF SOME HEAVY RAINFALL WHERE CONVECTION IS ABLE
TO SET UP ON TUESDAY. STILL THINK THERE WILL BE SUFFICIENT BREAKS
IN THE CLOUD COVER TO ALLOW FOR MAX TEMPERATURES IN THE 83 TO 87
DEGREE RANGE.
&&
.LONG TERM /TUESDAY NIGHT 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 /00Z TUESDAY THROUGH SATURDAY/...
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SHORT TERM /THROUGH TUESDAY/...
AS OF 645 PM MONDAY...PRED VFR CONDITIONS EXPECTED THROUGH 06Z
OUTSIDE OF SCT CONVECTION. SCT SHOWERS AND ISO TSTMS LIKELY TO
CONTINUE OVERNIGHT. COULD SEE BRIEF MVFR CIGS LATE TONIGHT INTO
EARLY TUE AM WITH MOIST BL AND LIGHT SW FLOW...THOUGH WILL KEEP
VFR AT THIS TIME DUE TO CONFIDENCE. BETTER COVERAGE TO
CONVECTION EXPECTED TUE WITH SW GUSTS 15-20KT.
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.-- End Changed Discussion --
&&
.MARINE...
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SHORT TERM /THROUGH TUESDAY/...
AS OF 630 PM MONDAY...NO SIG CHANGES NEEDED TO PREVIOUS FORECAST
AT THIS TIME. LATEST OBS SHOW SW WINDS 10-20KT WITH SEAS 2-5FT. LIGHT
TO MODERATE SOUTHWEST FLOW CONTINUES AROUND THE PERIPHERY OF HIGH
PRESSURE TO THE EAST. EXPECT SW WINDS OF 10 TO 15 KNOTS OVER THE
SOUTHERN SECTIONS AND GENERALLY 15 TO 20 KNOTS OVER THE CENTRAL
AND NORTHERN WATERS AND THE SOUNDS TONIGHT AND TUESDAY. SEAS WILL
GENERALLY RUN 2 TO 4 FEET WITH A FEW 5 FOOTERS POSSIBLE OVER THE
OUTER WATERS.
LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
AS OF 300 PM MON...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.-- End Changed Discussion --
&&
.MHX WATCHES/WARNINGS/ADVISORIES...
NC...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...CTC
NEAR TERM...CTC/CQD
SHORT TERM...CTC
LONG TERM...DAG
AVIATION...CQD/DAG
MARINE...CTC/CQD/DAG