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-- Discussion containing changed information from previous version are highlighted. --
000
FXUS61 KGYX 171353
AFDGYX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAY ME
953 AM EDT MON JUN 17 2013

.SYNOPSIS...
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A COLD FRONT WILL APPROACH FROM THE NORTHWEST TODAY...PUSHING
INTO NORTHERN NEW ENGLAND TONIGHT....BRINGING SHOWERS AND
SCATTERED THUNDERSTORMS WITH IT. THE SLOW MOVING FRONT WILL
FINALLY PUSH SOUTH OF THE REGION TUESDAY NIGHT. HIGH PRESSURE WILL
BUILD IN FOR WEDNESDAY AND THURSDAY. A WARM FRONT CROSSES THE AREA
ON FRIDAY...WITH ANOTHER CHANCE FOR SHOWERS. WARMER AND MORE HUMID
AIR IS EXPECTED FOR THE WEEKEND.
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&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
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WILL UPDATE TO LOWER CLOUD COVER AND THE CHANCE OF PRECIPITATION
THIS MORNING. OTHERWISE JUST MINOR TWEAKS TO THE GRIDDED FORECAST.

PREVIOUS DISCUSSION...

ANOTHER SHORTWAVE TROUGH MOVING THROUGH THE CENTRAL GREAT LAKES
EARLY THIS MORNING WILL MOVE QUICKLY EAST AND INTO NORTHERN NEW
ENGLAND THIS AFTERNOON. THIS... COMBINED WITH INCREASING LOW LEVEL
MOISTURE... WILL SET THE STAGE FOR SHOWERS AND SOME THUNDERSTORMS
THIS AFTERNOON. OVERALL CAPE VALUES OF 400 TO 800 ARE EXPECTED BY
EARLY AFTERNOON... WITH THE ATMOSPHERE BECOMING UNCAPPED BY AROUND
NOON. ANY AREAS WHICH CAN HOLD OFF ON DEVELOPING CONVECTION UNTIL
LATER IN THE DAY COULD POTENTIALLY TAP INTO BETTER INSTABILITY.
THE BETTER SYNOPTIC SCALE LIFT WITH THE SHORTWAVE TROUGH WILL
ARRIVE AROUND MID AFTERNOON AND WILL TRIGGER MORE WIDESPREAD
PRECIPITATION AND POSSIBLY A LINE OF THUNDERSTORMS. WIND PROFILES
TODAY SHOW MODERATE TO STRONG UNIDIRECTIONAL SPEED SHEAR WHICH
SUGGESTS THAT THUNDERSTORMS COULD GAIN BETTER ORGANIZATION INTO
LINES OR SUPERCELLS. HOWEVER... THE LIMITING FACTOR WILL BE
INSTABILITY. AS A RESULT... DO NOT EXPECT A SIGNIFICANT THREAT FOR
SEVERE WEATHER TODAY... THOUGH A FEW STRONG STORMS WITH GUSTY
WINDS OR SMALL HAIL ARE POSSIBLE... ESPECIALLY IF THUNDERSTORMS
GET ORGANIZED INTO LINES OR CLUSTERS OR IF CONVECTION IS
SUPPRESSED UNTIL LATER IN THE DAY LEADING TO GREATER INSTABILITY.
THE GREATEST THREAT AREA WOULD PROBABLY BE SOUTHERN NEW HAMPSHIRE.

TEMPERATURES TODAY WILL TOP OUT IN THE 70S TO LOW 80S. MAV
FORECAST HIGH OF 86 IN CONCORD SEEMED A BIT TOO HIGH... BUT IF
SHOWERS AND STORMS DO HOLD OFF UNTIL LATER IN THE DAY THEN MID 80S
ARE POSSIBLE IN THIS AREA.
-- End Changed Discussion --

&&

.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM TUESDAY/...
EXPECT AREA OF SHOWERS AND STORMS TO MOVE EAST AND WEAKEN BY THE
EARLY EVENING HOURS. SURFACE COLD FRONT WILL SAG SOUTH INTO
CENTRAL NEW HAMPSHIRE AND SOUTHWEST MAINE BY TUESDAY MORNING.
DRIER CONDITIONS WILL BE MOVING IN BEHIND IT TO THE NORTH... BUT
THE HUMID AIR MASS WILL REMAIN IN PLACE TO THE SOUTH OF THE
BOUNDARY. THIS COULD SET THE STAGE FOR MORE SHOWERS AND
THUNDERSTORMS ON TUESDAY ALONG AND SOUTH OF THE FRONT.

&&

.LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/...
STRONG RIDGE AT 500 MB WILL HOLD IN PLACE OVER THE SOUTH CENTRAL
UNITED STATES THROUGH THE WEEKEND. INITIALLY...WEAKLY AMPLIFIED
TROUGHING WILL HOLD TO OUR NORTH...WITH NORTHWEST FLOW OVERHEAD.
SO...AFTER THE COLD FRONTAL PASSAGE TUESDAY NIGHT...LOOK FOR
SEASONABLE TEMPERATURES...MAXES IN THE 70S...MINS IN THE 40S AND
50S...WITH GENERALLY DRY AIR...FOR WEDNESDAY INTO THURSDAY.

THE TROUGH LIFTS NORTHEAST BY LATE IN THE WEEK ALLOWING THE
RIDGING ALOFT TO SHIFT EAST. COULD SEE SOME SHOWERS/THUNDERSTORMS
ON FRIDAY AS A WARM FRONT WORKS THROUGH. WARMER AND MORE HUMID
AIR WORKS IN FOR THE WEEKEND. MODELS BEGIN TO DISAGREE AS TO HOW
QUICKLY AND HOW FAR SOUTH THE UPPER TROUGH DEVELOPS OVER THE
NORTHERN PLAINS AND GREAT LAKES...BUT ULTIMATELY THIS COULD
PRODUCE SOME PRECIPITATION/CONVECTION SUNDAY OR MONDAY.

&&

.AVIATION /14Z MONDAY THROUGH FRIDAY/...
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SHORT TERM /THROUGH TUESDAY/...VFR CONDITIONS EXPECTED TO START
THE DAY... BUT SHOWERS AND THUNDERSTORMS WILL QUICKLY FORM BY
16-20Z. CONFIDENCE IN THUNDERSTORMS AT EACH TERMINAL IS NOT HIGH
ENOUGH TO MENTION IN MOST TAFS ESPECIALLY CLOSER TO THE COAST.
SHOWERS AND STORMS MOVE EAST THIS EVENING WITH A COLD FRONT
DROPPING SOUTH INTO THE AREA. COULD SEE MORE SHOWERS AND A FEW
STORMS ON TUESDAY IN SOUTHERN NEW HAMPSHIRE AND SOUTHWEST MAINE.

LONG TERM...SOME FLIGHT RESTRICTIONS COULD BE POSSIBLE TUESDAY
NIGHT IN LOW CLOUDS/FOG...AS LINGERING LOW LEVEL MOISTURE HANGS ON
BEHIND A COLD FRONT. OTHERWISE...MAINLY VFR WEDNESDAY THRU FRIDAY.
-- End Changed Discussion --

&&

.MARINE...
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SHORT TERM /TODAY THROUGH TUESDAY/...WILL UPDATE TO INPUT LATEST
OBSERVED DATA. WILL LOWER THE SEAS FORECAST FOR TODAY AND TONIGHT
BASED ON CURRENT BUOY REPORTS. SOUTHWEST FLOW WILL GUST AROUND 20
KNOTS AND SEAS BUILD TO 4 FEET OVER THE OPEN WATERS THROUGH
TUESDAY AHEAD OF A SLOWLY APPROACHING COLD FRONT.

LONG TERM...NO FLAGS ANTICIPATED WEDNESDAY THRU FRIDAY...ALTHOUGH
LOW PRESSURE WELL TO THE SOUTH COULD INCREASE SWELL LATE IN THE
WEEK.
-- End Changed Discussion --

&&

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

&&

$$