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-- Discussion containing changed information from previous version are highlighted. --
000
FXUS61 KGYX 311103
AFDGYX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAY ME
703 AM EDT THU JUL 31 2014

.SYNOPSIS...
HIGH PRESSURE WILL BUILD IN FROM THE EAST TODAY THROUGH FRIDAY. A
WARM FRONT WILL LIFT NORTH FROM THE MID ATLANTIC STATES FRIDAY NIGHT
AND WILL STALL ALONG THE SOUTHERN NEW ENGLAND COAST SATURDAY
THROUGH SUNDAY. WEAK LOW PRESSURE WILL DEVELOP ON THE FRONT AND
WILL TRACK NORTHEAST THIS WEEKEND. A TRAILING COLD FRONT WILL
PUSH OFFSHORE MONDAY NIGHT. WEAK HIGH PRESSURE WILL BUILD IN FROM
THE WEST TUESDAY THROUGH WEDNESDAY.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
7 AM UPDATE...JUST A FEW MINOR ADJUSTMENTS TO THE GOING FORECAST
BASED ON LATEST TRENDS IN OBSERVATIONAL DATA. DENSE FOG STILL
PRESENT IN A LOT OF AREAS AND THEREFORE THE ADVISORY WILL CONTINUE
UNTIL 9 AM.

530 AM UPDATE...HAVE ISSUED A DENSE FOG ADVISORY FOR CUMBERLAND
COUNTY ON NORTHEAST. VISIBILITIES HAVE DROPPED TO A 1/4 MILE AT
MANY LOCATIONS. THE FOG SHOULD THIN AND LIFT BETWEEN 8 AND 9 AM.

PREVIOUSLY...

THE MAIN FORECAST CONCERN TODAY REVOLVES AROUND THE CHANCE FOR
SEVERE THUNDERSTORMS.

CAPE VALES ARE EXPECTED TO BE RELATIVELY LOW TODAY WITH MLCAPE
VALUES EXPECTED TO PEAK IN THE 500-800 J/KG RANGE. HOWEVER...THE
APPROACH OF A STRONG SHORT WAVE TROUGH WITH ATTENDANT ANOMALOUSLY
LOW MID LEVEL TEMPERATURES /500MB TEMPS AS LOW AS -17C/ AND STRONG
MID LEVEL FLOW/DEEP LAYER SHEAR WILL BE SUPPORTIVE OF WIDELY SCT
STRONG TO SEVERE THUNDERSTORMS THIS AFTERNOON. WITH SFC DEWPOINTS
MIXING OUT INTO THE LOWER TO MID 50S...SFC DEWPOINT DEPRESSIONS
SHOULD BE AS HIGH AS 20 TO 25 DEGREES THIS AFTERNOON AS SFC TEMPS
PUSH INTO THE 70S. THIS WILL CREATE AN ENVIRONMENT CONDUCIVE FOR
STRONG WIND GUSTS THROUGH EVAPORATIONAL COOLING. IN
ADDITION...SOME SEVERE HAIL WILL BE POSSIBLE AS WELL WITH SUCH
COLD TEMPERATURES ALOFT.

SEVERAL MODES OF CONVECTION ARE POSSIBLE TODAY...WITH ORGANIZED
MULTICELLS LIKELY ALONG WITH A FEW BOWING SEGMENTS AND PERHAPS A
COUPLE OF SUPERCELLS GIVEN THE DEEP LAYER SHEAR VALUES. STORMS ARE
EXPECTED TO INITIATE AROUND MIDDAY...WITH FIRST PREFERENCE GIVEN
TO NH AS THE FORCING FOR ASCENT ASSOCIATED WITH THE SHORT WAVE
TROUGH WILL MOVE INTO THAT AREA OF THE CWA FIRST. HOWEVER...A FEW
CELLS MAY INITIATE IN MAINE AROUND THAT TIME ALONG SUBTLE
CONVERGENCE ZONES AND IN AREAS OF DIFFERENTIAL HEATING. HIGHEST
POPS WILL BE ACROSS NORTHERN ZONES TODAY.

EARLY ON IN THE MORNING...STRATUS AND AREAS OF DENSE FOG WILL BE
PRESENT IN RIVER VALLEYS AS WELL AS MUCH OF THE CWA NORTHEAST OF
PORTLAND. THIS SHOULD LIFT EARLY ON THIS MORNING.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH FRIDAY NIGHT/...
ANY SHOWER AND THUNDERSTORM ACTIVITY WILL WANE QUICKLY EARLY THIS
EVENING WITH THE LOSS OF DAYTIME HEATING. THE BULK OF THE NIGHT IS
EXPECTED TO BE FAIR...WITH AREAS OF FOG ONCE AGAIN DEVELOPING
LATE.

ON FRIDAY...COLD AIR ALOFT WILL REMAIN. THIS WILL ACT IN TANDEM
WITH CONTINUED SOUTHERLY LOW LEVEL SFC FLOW TO AID IN A FEW
SHOWERS OR THUNDERSTORMS DURING THE AFTERNOON HOURS.
HOWEVER...ACTIVITY IS NOT EXPECTED TO BE AS WIDESPREAD AS
TODAY AND ISN/T EXPECTED TO BE SEVERE. JUST LOW CHANCE POPS AT
THIS TIME.

&&

.LONG TERM /SATURDAY THROUGH WEDNESDAY/...
WARM FRONT WILL LIFT NORTH FROM THE MID ATLANTIC COAST FRIDAY NIGHT
AND THIS BOUNDARY WILL HANG UP ALONG THE SOUTHERN NEW ENGLAND COAST BY
SATURDAY MORNING. NET RESULT WILL BE INCREASING HIGH CLOUDS
OVERNIGHT. STILL APPEARS ANY ASSOCIATED PRECIP WILL REMAIN WELL
SOUTH OF THE REGION. LOW TEMPS WILL RANGE FROM THE MID 50S TO LOWER
60S.

MAIN QUESTION WILL BE SENSIBLE WEATHER OVER THE WEEKEND. THE ECMWF
CONTINUES TO ADVERTISE A SOUTHERN STREAM WAVE AFFECTING THE REGION
SATURDAY WITH WIDESPREAD RAIN/SHOWERS. THE GFS CONTINUES TO KEEP
THE ACTIVITY OFFSHORE UNTIL SUNDAY NIGHT. THE ECMWF HAS SHOWN GOOD
RUN TO RUN CONSISTENCY WITH THE WET SATURDAY SCENARIO...SO PLACED
THE HIGHEST POPS OF THE WEEKEND ON SAT. HOWEVER...CONFIDENCE
REMAINS A BIT LOW AT THIS TIME.

EXPECT GRADUAL CLEARING MONDAY NIGHT AS LOW PRESSURE CONTINUES OFF
TO THE EAST AND DRIER NORTHWEST FLOW SETS UP BEHIND A WEAK COLD FRONT.
HIGH PRESSURE WILL BUILD IN FROM THE WEST FOR TUESDAY AND
WEDNESDAY AS COOL SUMMER WEATHER CONTINUES IN THE NORTHEAST.

&&

.AVIATION /11Z THURSDAY THROUGH MONDAY/...
SHORT TERM...IFR OR LOWER CONDITIONS EARLY THIS MORNING WILL GIVE
WAY TO VFR AS THE MORNING PROGRESSES. RKD MAY HOLD ONTO IFR
LONGER...PERHAPS INTO THE AFTERNOON. SHOWERS AND THUNDERSTORMS ARE
EXPECTED TO DEVELOP THIS AFTERNOON WITH ATTENDANT THREAT FOR LOWER
CONDITIONS...GUSTY SFC WINDS...AND HAIL. LOWER CONDITIONS MAY ONCE
AGAIN DEVELOP LATE TONIGHT IN SOME FOG AND STRATUS...BUT CHANCES
APPEAR LOWER THAN WHAT WE ARE SEEING EARLY THIS MORNING. FRIDAY IS
EXPECTED TO BE MAINLY VFR WITH SCT AFTERNOON SHOWERS.

LONG TERM...MVFR OR LOWER POSSIBLE ON SATURDAY IN SHOWERS...AND
POSSIBLY AGAIN SUNDAY NIGHT.

&&

.MARINE...
SHORT TERM...SUB-SCA CONDITIONS ARE EXPECTED TODAY THROUGH FRIDAY.
HOWEVER...AREAS OF DENSE FOG WILL BE PRESENT FROM TIME TO
TIME...ESPECIALLY OFF THE MID COAST OF MAINE. A FEW THUNDERSTORMS
MAY MOVE ACROSS THE WATERS BY LATE AFTERNOON TODAY.

LONG TERM...NO PROBLEMS NOTED.

&&

.GYX WATCHES/WARNINGS/ADVISORIES...
ME...DENSE FOG ADVISORY UNTIL 9 AM EDT THIS MORNING FOR MEZ012>014-
     019>022-024>028.
NH...NONE.
MARINE...NONE.

&&

$$

NEAR TERM...MLE