Area Forecast Discussion
Issued by NWS Portland, ME

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000
FXUS61 KGYX 112227
AFDGYX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAY ME
627 PM EDT FRI JUL 11 2014

.SYNOPSIS...
HIGH PRESSURE WILL BUILD INTO NEW ENGLAND TONIGHT THEN SLIDE OFF
THE COAST ON SATURDAY...PRODUCING ANOTHER DAY OF SUNNY AND
COMFORTABLE WEATHER.  A WARM FRONT WILL CROSS THE AREA SUNDAY
MORNING...WITH A FEW SCATTERED SHOWERS OR STORMS POSSIBLE ON
SUNDAY. MORE HUMID AIR MOVES IN SUNDAY NIGHT. A COLD FRONT WILL
APPROACH FROM THE WEST AND STALL OVER THE AREA THROUGH WEDNESDAY.
THIS WILL LEAD TO A WARM AND HUMID PERIOD WITH SCATTERED SHOWERS
OR THUNDERSTORMS. THE COLD FRONT WILL PUSH THROUGH THE REGION AT
THE END OF THE WEEK WITH SOME IMPROVEMENT BY FRIDAY.

&&

.NEAR TERM /TONIGHT/...
630PM UPDATE...
HAVE MADE ONLY MINOR MODIFICATIONS TO THE HOURLY TEMPERATURE AND
SKY FORECAST FOR THE NEXT FEW HOURS. HIGH PRESSURE HAS KEPT THE
WIND FLOW IN THE AREA LIGHT... WITH A SEA BREEZE MAKING PRETTY
SUBSTANTIAL INLAND PENETRATION THIS AFTERNOON. EXPECT QUIET
WEATHER TO CONTINUE... WITH LOWS TONIGHT A FEW DEGREES WARMER THAN
LAST NIGHT.

ORIGINAL DISCUSSION...
SURFACE HIGH PRESSURE WILL CREST OVER THE REGION TONIGHT. ANY
FAIR WEATHER CLOUDS FROM THE AFTERNOON DIURNAL HEATING WILL QUICKLY
DISSIPATE AFTER SUNSET ALLOWING FOR A CLEAR CALM NIGHT. SOME PATCHY
VALLEY FOG ONCE AGAIN POSSIBLE IN THE CONNECTICUT RIVER VALLEY
LATE. TEMPERATURES WILL ONCE AGAIN COOL INTO THE 40S TO MID 50S
DUE TO RADIATIONAL COOLING. MODEL GUIDANCE GENERALLY WITHIN A FEW
DEGREES TONIGHT SO USED A BLEND FOR MIN TEMPERATURE FORECAST.

&&

.SHORT TERM /SATURDAY AND SATURDAY NIGHT/...
THE CENTER OF HIGH PRESSURE WILL SLOWLY MOVE OFFSHORE BUT WITH A DRY
WSW FLOW ALOFT. ANOTHER MOSTLY SUNNY DAY EXPECTED. TEMPERATURES
WILL BE A FEW DEGREES WARMER. ALONG THE COAST AN AFTERNOON SEA BREEZE
IS EXPECTED THAT MAY KEEP TEMPERATURES ALONG THE COAST A LITTLE COOLER.

SATURDAY NIGHT THE RETURN WARMER SOUTHERLY FLOW WILL BE LIGHT BUT
ALLOWING A SLOW INCREASE IN DEW POINTS. SOME MID/HIGH CLOUDS WILL
OVERSPREAD THE REGION SATURDAY NIGHT SO OVERNIGHT TEMPERATURES
SHOULD BE NOT AS COOL WITH LOWS IN THE 50S TO LOWER 60S. USED A
BLEND OF THE MODELS FOR TEMPERATURES.

&&

.LONG TERM /SUNDAY THROUGH FRIDAY/...
500 MB TROUGHING DIGS EQUATORWARD OVER THE GREAT LAKES SUNDAY AND
SUNDAY NIGHT...PUSHING A SURFACE WARM FRONT ACROSS THE REGION SUNDAY
WHICH COULD SET OFF A FEW SCATTERED SHOWERS... ESPECIALLY IN WESTERN
AND NORTHERN ZONES. MORE HUMID AIR BEGINS TO WORK IN AS S-SW FLOW
DEVELOPS...ALTHOUGH SUNDAY WILL BE MORE OF THE TRANSITION DAY WITH
DEW POINTS REACHING INTO THE LOW-MID 60S AND HIGHS UPPER 70S TO
LOW 80S...WITH A MIX OF SUN AND CLOUDS. THE THREAT FOR
SHOWERS/THUNDERSTORMS WILL CONTINUE OVERNIGHT AS THE SURFACE COLD
FRONT CREEPS IN FROM THE WEST. SUNDAY WILL TURN HUMID WITH LOWS IN
THE 60S.

BY MONDAY...START TO SEE OMEGA BLOCKING DEVELOP ACROSS THE
ATLANTIC AT 500 MB WITH STRONG ATLANTIC RIDGING. THIS WILL HOLD UP
THE PROGRESS OF THE COLD FRONT SOMEWHERE IN THE VICINITY OF THE
FORECAST AREA AS IT LINES UP WITH FLOW ALOFT. MONDAY WILL BE HUMID
WITH DEW POINTS IN THE MID 60S TO AROUND 70 AND WE WILL SCATTERED
SHOWERS/THUNDERSTORMS WITH THE FRONT NEARBY... AND A MIX OF SUN
AND CLOUDS. MONDAY NIGHT WILL BE EVEN LESS COMFORTABLE WITH LOWS
MID 60S TO AROUND 70. ON TUESDAY... IT LOOKS LIKE A WEAK WAVE
WILL RUN NE ALONG THE FRONT AND WILL SEE MORE IN THE WAY OF CLOUDS
AND A BETTER CHANCE FOR SHOWERS/THUNDERSTORMS DURING THE DAY WITH
HIGHS AGAIN UPPER 70S TO LOW 80S.

THE 12Z EURO JUST CAME IN MUCH MORE PROGRESSIVE WITH THE SYSTEM
AND CLEARS IT OUT BY LATE WEDNESDAY... WHILE THE 12Z GFS STALLS
IT JUST OFFSHORE... AS DOES THE GFS ENSEMBLE MEAN. KEEPING THE
CHANCE POPS FOR WEDNESDAY... ALTHOUGH COULD BE SOME LESS HUMID
CONDITIONS IF THE FRONT MAKES IT THROUGH. WILL HAVE TO WATCH FOR
HOW THE MODELS HANDLE THIS BLOCK AND THE STRENGTH OF THE
ATLANTIC RIDGING... SO FORECAST CONFIDENCE LATE IN THE WEEK IS
LOW... BUT ASSUMING THE FRONT MAKES IT THROUGH... EXPECT SOMEWHAT
LESS HUMID AIR BEHIND THE FRONT FOR THURSDAY/FRIDAY.

&&

.AVIATION /22Z FRIDAY THROUGH WEDNESDAY/...
SHORT TERM...VFR CONDITIONS THRU SATURDAY NIGHT EXCEPT PATCHY
VALLEY FOG POSSIBLE 06-12Z AT KLEB.

LONG TERM...WHILE VFR LOOKS PREDOMINANT SUNDAY AND MONDAY... SOME
SCATTERED SHOWERS/THUNDERSTORMS COULD BRIEFLY REDUCE CONDITIONS
BOTH SUNDAY AND MONDAY DURING THE DAY. STRATUS AND FOG CAN BE
EXPECTED TO BRING CONDITIONS TO IFR SUNDAY NIGHT AND AGAIN MONDAY
NIGHT. THE BEST CHANCE FOR FOR A MORE PERSISTENT PERIOD OF FLIGHT
RESTRICTIONS WILL BE TUESDAY IN SHOWERS/THUNDERSTORMS.

&&

.MARINE...
SHORT TERM...HIGH PRESSURE BUILDS INTO NEW ENGLAND TONIGHT THEN
MOVES OFFSHORE SATURDAY KEEPING WINDS AND SEAS WELL BELOW SCA
LEVELS THRU SATURDAY NIGHT. LIGHT AND VARIABLE WINDS ARE EXPECTED
TONIGHT. AN ONSHORE FLOW AROUND THE DEPARTING HIGH WILL BE
ENHANCED BY A SEA BREEZE ON SATURDAY AFTERNOON INTO THE EVENING.

LONG TERM...WHILE S-SW FLOW BECOME PERSISTENT SUNDAY AFTERNOON TROUGH
TUESDAY... WINDS WILL GENERALLY REMAIN BELOW SCA LEVELS... ALTHOUGH
COULD APPROACH 25 KT SUNDAY NIGHT INTO MONDAY. THE PERSISTENT FLOW WILL
LIKELY BRING SEAS UP TO AROUND 5 OR 6 FT IN SWELL LATE MONDAY INTO
TUESDAY NIGHT.

&&

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

&&

$$

NEAR TERM UPDATE... KIMBLE




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