Area Forecast Discussion
Issued by NWS Portland, ME

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000
FXUS61 KGYX 120658
AFDGYX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAY ME
258 AM EDT SAT JUL 12 2014

.SYNOPSIS...
HIGH PRESSURE MOVES OFF THE COAST TODAY GIVING US ANOTHER PLEASANT
SUMMER DAY. A WARM FRONT PUSHES TO THE NORTHEAST TONIGHT BRINGING
IN MORE HUMID AND UNSTABLE AIR ON SUNDAY WITH AN INCREASING RISK
OF SHOWERS AND THUNDERSTORMS. THE WARM HUMID AIRMASS WILL LINGER FOR
MONDAY AND TUESDAY IN ADVANCE OF A SLOW-MOVING COLD FRONT. THE
COLD FRONT IS EXPECTED TO EXIT THE COAST BY LATE WEDNESDAY. HIGH
PRESSURE WILL BUILD TO THE SOUTH OF THE AREA THURSDAY AND FRIDAY.

&&

.NEAR TERM /THROUGH TODAY/...
THE SFC HIGH SLIDES OFFSHORE TODAY GIVING US LOTS OF SUNSHINE
TODAY. A RETURN FLOW OF S SW WINDS WILL BRING IN WARMER AIR OVER
INLAND AREAS...ESPECIALLY NH INTO THE ME MT/FOOTHILL ZONES...WITH
HIGHS EXPECTED TO REACH THE 80S WITH SOME UPPER 70S IN THE
MOUNTAINS. THE S SW FLOW WILL BE ENHANCED BY A SEA BREEZE
BRINGING IN COOLER OCEAN AIR ALONG THE COAST. THIS WILL LIMIT
HIGHS IN THE 70S ALONG THE COAST...WITH THE MID COAST THE COOLEST
WITH HIGHS BARELY REACHING THE LOWER 70S ALONG THE IMMEDIATE
SHORELINE. WITH THE PRESSURE GRADIENT FROM THE S SW THE COOL OCEAN
AIR WILL PUSH INLAND...JUST SHORT OF THE FOOTHILLS THIS AFTERNOON
WHICH WILL LEVEL OFF TEMPS AT PLACES LIKE LEW...AUG AND WVL.

&&

.SHORT TERM /TONIGHT THROUGH 6 PM SUNDAY/...
A WARM FNT SURGES TO THE NE TNGT AS THE HIGH DRIFTS FURTHER OUT TO
SEA. THUS CLOUDS WILL BE ON THE INCREASE TNGT WITH LOW TEMPS
MILDER THAN LAST NGT...EXPECTING LOWS IN THE 50S N AND UPPER 50S
TO LOWER 60S S. DEW POINTS WILL BE ON THE RISE AS WELL SUCH THAT
TEMP DEW POINT SPREADS WILL BE VERY SMALL WHICH MAY ALLOW FOR SOME
F TO FORM...THOUGH INCREASING CLOUDS WILL OFFSET THAT TO SOME DEGREE.

THE WARM FNT WILL USHER IN A WARMER...MORE HUMID AND UNSTABLE AIR
MASS FOR SUNDAY. THE INSTABILITY AS BEST SHOWN BY CAPE VALUES AND
NEGATIVE LI VALUES REACHES THE N/MT/FOOTHILL AND WRN NH ZONES
MORE SO THAN ALONG THE COAST. THE AXIS OF THE HIGHEST 850 MB THETA
E VALUES SURGES TO THE NE ACROSS THE ENTIRE FCST AREA ON SUNDAY AS
THE LOW LVL FLOW FROM THE SFC TO 700 MB INCREASES ALONG WITH
VEERING WINDS. THIS WILL INCREASE THE SHEAR TO ENHANCE TSTM
ACTIVITY. SPC IS INDICATING A RISK OF TSTMS BEING STRONG TO MAYBE
SVR. WILL PUT IN ENHANCE WORDING OF GUSTY WINDS, HEAVY RAIN AND
SMALL HAIL WITH ANY TSTMS IN THE MID TO LATE AFTERNOON HOURS AWAY
FROM THE COAST. THE INCREASING CLOUDS AND SCT SHRA/TSTMS WILL
HOLD TEMPS BACK ON SUNDAY WITH HIGHS MOSTLY IN THE 70S WITH SOME
LOWER 80S S. IF THERE IS MORE SUNSHINE THEN HIGHS COULD END UP
BEING A BIT WARMER... ESPECIALLY AWAY FROM THE COAST. ALONG THE
COAST ONSHORE S SW WINDS WILL HAVE A COOLING AFFECT...AND WILL
ALSO OFFSET TSTM ACTIVITY ALONG THE COAST AS IS ALSO INDICATED BY
FCST INSTABILITY PARAMETERS /CAPE AND LI/. SFC DEW POINTS WILL BE
ON THE RISE... INTO THE 60S JUST ABOUT EVERYWHERE...WITH THE
POTENTIAL OF REACHING 70.

&&

.LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/...
THE MODELS ARE IN GENERAL AGREEMENT ON THE LONGWAVE PATTERN
WELL INTO NEXT WEEK. WE BEGIN THE PERIOD WITH A WEST-SOUTHWEST
UPPER FLOW THAT INTRODUCES A BRIEF WARM UP ALONG WITH RISING
HUMIDITY LEVELS...FOLLOWED QUICKLY BY AN EASTERN TROUGH AND COOLER
UNSETTLED WEATHER. IN THE DAILIES...A WARM FRONT WILL CROSS THE
AREA SUNDAY WITH A WARM HUMID AIRMASS TO FOLLOW FOR MONDAY AND
TUESDAY IN ADVANCE OF A SLOW-MOVING COLD FRONT. THE COLD FRONT IS
EXPECTED TO EXIT THE COAST BY LATE WEDNESDAY. HIGH PRESSURE WILL
BUILD TO THE SOUTH OF THE AREA THURSDAY AND FRIDAY.

&&

.AVIATION /06Z SATURDAY THROUGH WEDNESDAY/...
SHORT TERM /THROUGH SUNDAY/...VFR TODAY AND TNGT...EXCEPT PATCHY
VALLEY F EARLY THIS MORNING MAY AFFECT LEB. AREAS OF F POSSIBLE
TNGT WHICH MAY IMPACT TAF SITES LIKE LEB...HIE AND CON.

LONG TERM...

MON - TUE...IFR IN COASTAL AM FOG...OTHERWISE AREAS OF MVFR IN
SHOWERS AND TSTMS.

&&

.MARINE...
SHORT TERM /TODAY THROUGH SUNDAY/...HIGH PRESSURE MOVING OFFSHORE
TODAY WITH A WARM FNT PUSHING NE INTO THE REGION TNGT. S SW FLOW
ENHANCED BY A SEA BREEZE TODAY. STILL EXPECT WINDS/SEAS BELOW SCA
LEVELS. THE S SW FLOW INCREASES SUNDAY AS THE WARM FNT MOVES TO
THE NE AND THE SFC PRESSURE GRADIENT INCREASES. WIND GUSTS MAY
REACH MINIMAL SCA LEVELS OVER THE OPEN WATERS. THIS WILL FORCE
SEAS TO BUILD...AND THEY MAY ALSO REACH SCA LEVELS SUNDAY
AFTERNOON OVER THE OPEN WATERS.

LONG TERM...

MON - TUE...SMALL CRAFT WINDS AND SEAS ARE POSSIBLE.

&&

.GYX WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
NH...NONE.
MARINE...NONE.

&&

$$





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