Area Forecast Discussion
Issued by NWS Portland, ME

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000
FXUS61 KGYX 070726
AFDGYX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE KGYX
326 AM EDT THU MAY 7 2015

.SYNOPSIS...
HIGH PRESSURE WILL GRADUALLY SLIDE OFFSHORE TODAY. A COLD FRONT
WILL SLOWLY APPROACH FROM THE WEST FRIDAY AND WILL STALL OVER
NORTHERN NEW ENGLAND ON SATURDAY. SEVERAL AREAS OF WEAK LOW
PRESSURE WILL TRACK NORTHEAST ALONG THE FRONT ON SUNDAY. THE FRONT
WILL REMAIN STALLED OVER THE REGION ON MONDAY. LOW PRESSURE
TRACKING NORTHEAST OUT OF THE GREAT LAKES WILL LIFT THE FRONT
NORTHWARD MONDAY NIGHT AND WILL DRIVE A COLD FRONT THROUGH THE
AREA ON TUESDAY.

&&

.NEAR TERM /THROUGH TODAY/...
THE SURFACE AND UPPER RIDGE AXIS WILL REMAIN OVER THE REGION
PROVIDING ANOTHER SUNNY MILD DAY. WINDS WILL BE SLIGHTLY LOWER
THAN YESTERDAY BUT SOME GUSTINESS IS STILL EXPECTED IN THE
AFTERNOON.  AFTERNOON SEABREEZES WILL DEVELOP ALONG THE COAST
KEEPING TEMPERATURES COOLER IN THOSE AREAS. USED A BLEND OF MODELS
FOR MAX TEMPERATURES TODAY.

&&

.SHORT TERM /TONIGHT THROUGH 6 PM FRIDAY/...
HIGH PRESSURE SLIDES OFF THE COAST TONIGHT BUT STILL ANOTHER
MOSTLY CLEAR NIGHT WITH LIGHT WINDS.

ON FRIDAY A MAJOR CHANGE IS ON THE WAY AS HIGH PRESSURE MOVES
WELL OFFSHORE ALLOWING A BROAD ONSHORE FLOW TO DEVELOP ACROSS
MAINE AND EVEN REACHING WELL INTO NEW HAMPSHIRE. THIS WILL KEEP
TEMPERATURES MUCH COOLER WITH HIGHS ONLY REACHING NEAR 50 ALONG
THE COAST TO NEAR 60 INLAND. OVER WESTERN AND SOUTHWEST NEW
HAMPSHIRE TEMPERATURES WILL BE WARMEST REACHING INTO THE 70S.
OCEAN CLOUDS WILL LIKELY DEVELOP AND MOVE ONSHORE IN THE
AFTERNOON.

&&

.LONG TERM /FRIDAY NIGHT THROUGH WEDNESDAY/...
ONSHORE FLOW FRIDAY NIGHT WILL LEAD TO LOW CLOUDS AND FOG IN
COASTAL AREAS. FOR SATURDAY...LOW CLOUDS AND FOG WILL GRADUALLY
GIVE WAY TO PARTLY SUNNY SKIES AS FLOW BECOMES MORE
SOUTHWESTERLY.

FORECAST BECOMES A BIT MORE COMPLICATED SATURDAY AND SUNDAY AS
FRONTAL BOUNDARY NORTH OF THE REGION SLIPS SLOWLY SOUTHWARD.
MODELS HAVE NOT BEEN CONSISTENT WITH THE MOVEMENT OF THE FRONT
WHICH WILL BE THE FOCUS OF SCATTERED SHOWERS AND POSSIBLE
THUNDERSTORMS. NORTH OF THE FRONT TEMPERATURES WILL BE MUCH COOLER
THAN SOUTH OF THE FRONT...EXCEPT IN AREAS AFFECTED BY SEA BREEZES.

LATEST ECMWF SLOWS THE FRONT CONSIDERABLY...THEN STALLS IT ACROSS
THE FORECAST AREA MONDAY. GFS IS ALSO SLOWER THAN PREVIOUS
RUNS...BUT NOT AS SLOW AS ECMWF. WITH LATEST MODEL RUNS AND RECENT
TRENDS WILL KEEP SATURDAY DRY ACROSS FORECAST AREA WITH ONLY A
CHANCE OF SHOWERS/TSTMS ACROSS THE NORTHERN MOUNTAINS. WITH SW
FLOW...TEMPS SATURDAY SHOULD WARM MORE THAN FRIDAY...BUT SEA
BREEZE WILL CONTINUE TO KEEP COASTAL AREAS COOL.

SUNDAY`S FCST WILL DEPEND ON POSITION OF FRONT WITH GFS SHOWING
SHOWERS/TSTMS ACROSS MUCH OF THE AREA WHILE ECMWF KEEPS FRONTAL
BOUNDARY AND SHOWERS NORTH OF REGION. HAVE COMPROMISED AND BROUGHT
CHANCE OF SHOWERS TO ALL AREAS.

FRONT SLIPS A BIT FARTHER SOUTH FOR MONDAY AND WEAK DISTURBANCE
WILL ONCE AGAIN BRING THE THREAT OF SHOWERS/TSTMS TO THE REGION.

ANOTHER FRONT MOVING EAST FROM THE MID-WEST WILL CROSS THE REGION DURING
THE DAY TUESDAY AND SHOULD LEAD TO A CHANCE OF SHOWERS/TSTMS.

IMPROVING WEATHER EXPECTED EVERYWHERE FOR WEDNESDAY.


&&

.AVIATION /06Z THURSDAY THROUGH MONDAY/...
SHORT TERM...VFR CONDITIONS THROUGH EARLY FRIDAY. SOME MVFR
CONDITIONS MAY DEVELOP ALONG COASTAL AREAS FRIDAY AFTERNOON AS THE
DEVELOPING ONSHORE FLOW MAY DEVELOP LOW CLOUDS OFF THE OCEAN.

LONG TERM...
MVFR CONDITIONS AND POSSIBLE IFR CONDITIONS IN FOG SATURDAY NIGHT.
THEN MOSTLY VFR CONDITIONS SATURDAY AFTER LOW CLOUDS AND ANY FOG
BURN OFF. VFR WITH MVFR CONDITIONS POSSIBLE SUNDAY THROUGH
TUESDAY IN SCATTERED SHOWERS AND TSTMS. &&

.MARINE...
SHORT TERM...NO FLAGS EXPECTED TODAY AND TONIGHT AS HIGH PRESSURE
REMAINS OVER THE REGION. A SCA FOR SEAS OVER THE OUTER WATERS MAY
BE NEEDED FRIDAY DUE TO A DEVELOPING BROAD DEVELOPING EASTERLY
FETCH.

LONG TERM...SCA MAY BE NEEDED FOR SATURDAY INTO MONDAY...MAINLY
FOR SEAS.

&&

.FIRE WEATHER...
THE RED FLAG WATCH AREAS HAVE BEEN UPGRADED TO RED FLAG WARNINGS
FROM 11AM TO 8PM TODAY.

CONTINUED EXTREMELY DRY CONDITIONS AND LOW RELATIVE HUMIDITY
LEVELS IN THE LOWER 20S WARRANT ANOTHER RED FLAG WARNING TODAY
EVEN THOUGH WINDS WILL BE A BIT LOWER TODAY. SOME GUSTINESS IS
STILL EXPECTED IN THE AFTERNOON OVER SOME AREAS.  EXCLUDED ONLY
SOUTHERN NEW HAMPSHIRE...WHERE WINDS WILL BE LIGHTER AND FUELS ARE
A BIT GREENER IN THAT AREA.

FRIDAY A MAJOR CHANGE IS ON THE WAY WITH A MUCH COOLER AND MOIST MARITIME
AIR MASS TO MOVE OVER THE AREA DUE TO AN ONSHORE FLOW THAT
DEVELOPS. RELATIVE HUMIDITIES WILL BE MUCH HIGHER ALLEVIATING ANY
ELEVATED FIRE DANGER RISK.

&&

.GYX WATCHES/WARNINGS/ADVISORIES...
ME...RED FLAG WARNING FROM 11 AM THIS MORNING TO 8 PM EDT THIS
     EVENING FOR MEZ007>009-012>014-018>028.
NH...RED FLAG WARNING FROM 11 AM THIS MORNING TO 8 PM EDT THIS
     EVENING FOR NHZ001>006-009-010.
MARINE...NONE.

&&

$$




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