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000
FXUS61 KGYX 132111 AAA
AFDGYX

AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE GRAY ME
511 PM EDT THU JUN 13 2013

.SYNOPSIS...
LOW PRESSURE WILL PASS OUT TO SEA SOUTH OF NEW ENGLAND TONIGHT. A
COLD FRONT WILL DROP SOUTH THROUGH THE REGION ON FRIDAY. HIGH
PRESSURE WILL BUILD IN BEHIND THE FRONT FRIDAY NIGHT AND SATURDAY.
HIGH PRESSURE WILL SHIFT OFFSHORE SOUTH OF NEW ENGLAND SATURDAY
NIGHT. A WARM FRONT WILL LIFT NORTHEAST THROUGH THE REGION ON SUNDAY
AND WILL PUSH NORTH OF THE AREA BY MONDAY. LOW PRESSURE WILL HEAD
EAST FROM THE LOWER GREAT LAKES MONDAY NIGHT AND WILL MOVE INTO
CENTRAL NEW ENGLAND BY LATE IN THE DAY TUESDAY. LOW PRESSURE WILL
CONTINUE EAST INTO THE MARITIMES TUESDAY NIGHT. HIGH PRESSURE WILL
BUILD IN FROM THE WEST WEDNESDAY THROUGH THURSDAY.

&&

.NEAR TERM /UNTIL 6 AM FRIDAY MORNING/...
UPDATE...FORECAST LOOKS ON TRACK AS FAR AS POP AND WX GO...WITH
JUST SOME MINOR TWEAKS TO TEMPS AND SKY IN THE FIRST PERIOD.
LATEST MESOSCALE MODELS APPEAR TO HAVE A GOOD HANDLE ON RA
SHIELD...AND MATCH POP DISTRIBUTION WELL.

PREVIOUS DISCUSSION...AS OF 3 PM...SHIELD OF MAINLY LIGHT RAIN
HAS REACHED APPROX A KLEB-KLCI-KDAW LINE. THIS LINE WILL CONTINUE
TO MOVE GRADUALLY NORTHEASTWARD THE REST OF THE AFTERNOON INTO THE
EVENING...THEN WILL EVENTUALLY STOP AND PIVOT BACK SOUTHEASTWARD.
THIS SHARP CUTOFF BETWEEN RAIN AND NO RAIN HAS BEEN DIFFICULT TO
FORECAST THE LAST FEW DAYS AND STILL REMAIN A BIT OF A CHALLENGE.

AT THIS TIME...BASED ON LATEST RADAR DATA AND MODEL GUIDANCE...THE
LEADING EDGE OF THE RAIN WILL PROBABLY MOVE NORTHEASTWARD ANOTHER
50 OR SO MILES BEFORE SLOWLY PIVOTING BACK OUT. THIS PROGRESSION
PRETTY CLOSELY RESEMBLES THE NORTHERN EDGE OF THE NAM 700-500MB
FRONTOGENESIS MAX. THEREFORE...WE EXPECT SOME LIGHT RAIN TO GET
INTO PORTLAND...BUT MAY NOT GET NORTH OF A KHIE-KIZG-KLEW-KIWI
LINE...ALTHOUGH WE MUST ACCOUNT FOR SOME ERROR...PERHAPS ON THE
ORDER OF UP TO 20 MILES EITHER SIDE. ALSO...A FEW LIGHT RAIN
SHOWERS MAY OCCUR THIS EVENING IN THE NORTHERN WHITES ASSOCIATED
WITH THE COLD POOL ALOFT UP THAT WAY.

AS FAR AS RAINFALL AMOUNTS GO...BEST ESTIMATE AT THIS TIME IS FOR
A HALF INCH TO AN INCH ACROSS THE EXTREME SOUTHERN TIER OF THE
CWA...WITH MUCH LESSER AMOUNTS NORTH OF THERE. NO FLOODING ISSUES
ARE FORESEEN.

THE RAIN ACTIVITY SHOULD HAVE MOSTLY ENDED BY AROUND SUNRISE. SOME
PATCHY FOG WILL BE POSSIBLE LATE.

&&

.SHORT TERM /6 AM FRIDAY MORNING THROUGH FRIDAY NIGHT/...
COLD FRONT TO MOVE ACROSS THE AREA FRIDAY AFTERNOON. WEAK LOW
LEVEL CONVERGENCE COUPLED WITH INCREASINGLY COLD AIR ALOFT MAY AID
IN SCATTERED SHOWERS AND PERHAPS A TSTM AWAY FROM THE IMMEDIATE
COAST. THEREAFTER...CLEARING IS FORESEEN DURING THE EVENING HOURS.

&&

.LONG TERM /SATURDAY THROUGH THURSDAY/...
HIGH PRESSURE WILL PRODUCE A VERY NICE WEEKEND IN THE NORTHEAST. A
MODERATE NORTHWEST BREEZE WILL USHER IN MILD...LOW HUMIDITY AIR INTO
THE REGION. WILL SEE SUNSHINE MIXING WITH AFTERNOON CLOUDS WITH HIGH
TEMPS RANGING THROUGH THE 70S TO NEAR 80.

AFTER A CLEAR AND CHILLY SATURDAY NIGHT WITH HIGH PRESSURE CRESTING
OVER THE REGION...SUNDAY WILL FEATURE MORE SUN AND MODERATING TEMPS
AS RETURN FLOW BRINGS WARMER AIR BACK INTO THE REGION. A WEAK WARM
FRONT WILL LIFT INTO SOUTHERN AND WESTERN ZONES DURING THE DAY BUT
SHOULD SEE LITTLE MORE THAN PASSING CLOUDS AS ANY FORCING ALONG
THIS BOUNDARY REMAINS WEAK AND DISORGANIZED. WILL TACK ON 3 TO 5
DEGREES TO SATURDAYS HIGHS WITH MOST OF THE AREA GETTING INTO THE
MID 70S TO LOWER 80S. SOME DEGREE OF ONSHORE FLOW WILL HOLD
READINGS IN THE LOWER TO MID 70S ALONG THE COAST.

WARM AND MUGGY WEATHER COMES BACK IN FORCE ON MONDAY. WILL SEE A
CHANCE OF SHOWERS AND THUNDERSTORM IN THE AFTERNOON. WILL SEE HIGHS
INLAND IN THE LOWER TO MID 80S WITH 70S TO NEAR 80 ALONG THE COAST.

CLOUDS WILL BE ON THE INCREASE MONDAY NIGHT AS LOW PRESSURE MOVES
EAST FROM THE GREAT LAKES. MAY SEE A FEW SHOWERS BY DAYBREAK IN THE
CONNECTICUT VALLEY BUT THE MAJORITY OF THE PRECIP WILL COME DURING
THE DAY TUESDAY. SOME BIG DIFFS BETWEEN MODELS AT THIS POINT SO
WILL LIKELY SEE CHANGES TO TRACK AND TIMING IN THE COMING DAYS.

WITH THE PREVIOUS MENTIONED MODEL DIFFS...FORECAST CONFIDENCE
RATHER LOW FOR MID WEEK AND BEYOND.

&&

.AVIATION /21Z THURSDAY THROUGH TUESDAY/...
SHORT TERM...VFR CONDITIONS WILL LIKELY DETERIORATE TO MVFR AND
POSSIBLY ISOLD IFR TONIGHT IN SHOWERS...ESPECIALLY ACROSS SOUTHERN
NH. IMPROVEMENT IS FORESEEN AFTER SUNRISE FRIDAY WITH VFR
CONDITIONS RETURNING...POSSIBLY SOONER. SCT SHOWERS FRIDAY
AFTERNOON SHOULDN/T CAUSE WIDESPREAD SUB-VFR CONDITIONS. VFR
FRIDAY NIGHT.

LONG TERM...VFR SATURDAY THROUGH MONDAY. MVFR/IFR CEILINGS
DEVELOPING TUESDAY.

&&

.MARINE...
SHORT TERM...MARGINAL SCA FOR SEAS REMAINS UP FOR ANZ154 THROUGH
EARLY FRIDAY AFTERNOON. OTHERWISE...RELATIVELY TRANQUIL CONDITIONS
ARE FORESEEN THROUGH FRIDAY NIGHT.

LONG TERM...SCA`S MAY BE NEEDED ON SATURDAY AND AGAIN ON TUESDAY.

&&

.GYX WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
NH...NONE.
MARINE...SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS FROM MIDNIGHT TONIGHT
     TO 3 PM EDT FRIDAY FOR ANZ154.

&&

$$

NEAR TERM...LEGRO