Area Forecast Discussion
Issued by NWS Portland, ME

Home | Current Version | Previous Version | Text Only | Print | Product List | Glossary On
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50
000
FXUS61 KGYX 210437
AFDGYX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAY ME
1237 AM EDT TUE OCT 21 2014

.SYNOPSIS...
LOW PRESSURE OVER THE EASTERN GREAT LAKES WILL MOVE TO THE
SOUTHEAST TONIGHT AND TUESDAY AND WILL INTENSIFY SOUTH OF LONG
ISLAND TUESDAY NIGHT....BRINGING AN EXTENDED PERIOD OF RAIN TO
THE AREA. LOW PRESSURE WILL MEANDER OFF THE SOUTHERN NEW ENGLAND
COAST WEDNESDAY THROUGH FRIDAY BEFORE DRIFTING OFF TO THE
NORTHEAST ON SATURDAY. A COLD FRONT WILL CROSS THE AREA SUNDAY
FOLLOWED BY A RIDGE OF HIGH PRESSURE FOR MONDAY.

&&

.NEAR TERM /UNTIL 6 AM THIS MORNING/...
MIDNIGHT UPDATE: MINOR TWEAKS TO CURRENT OBSERVATIONS.
7PM UPDATE: TWEAKED EVENING SKY GRIDS TO REFLECT MORE CLOUD
COVER. INPUT LATEST OBS DATA AND TEMPS/DEWPTS LOOK ON TRACK. NO
OTHER CHANGES ATTM.

PREV DISC:
WEAK 500MB RIDGING BETWEEN CLOSED LOW EXITING THE MARITIMES TO
THE NE...AND DEEPEN TROUGH OVER THE PH VLY WILL ALLOW FOR A MAINLY
DRY NIGHT...ALTHOUGH THIS WILL ALLOW FOR MORE STAGNANT SFC FLOW
OVERNIGHT...AS THE MID LVLS BECOME MORE SRLY TOWARD DAYBREAK. LOOK
FOR THE ONSHORE TO DEVELOP STRATOCU...ESPECIALLY OVER THE COASTAL
PLAIN AND IN THE SE UPSLOPE AREAS. HIGH AND MID CLOUDS WILL MOVE
IN FROM THE WEST IN ADVANCE OF THE SYSTEM TO OUR WEST..WHICH
BEGINS TO CLOSE OFF BY MORNING. THERE WILL BE A SLIGHT CHC OF A
VERY LIGHT SHOWER TOWARD DAYBREAK. TEMPS WILL DROP OFF QUICKLY
THIS EVENING...AS CLEAR SKIES HOLD UNTIL A ROUND MIDNIGHT...BUT
ONCE THE CLOUDS MOVE IN...TEMPS WILL REMAIN STEADY THRU THE LATTER
PART OF THE NIGHT....WITH LOWS MID TO UPPER 30S N AND 40 TO 45
ELSEWHERE.

&&

.SHORT TERM /6 AM THIS MORNING THROUGH 6 PM WEDNESDAY/...
SFC FLOW REMAINS GENERALLY WEAK...AND WILL LKLY SEE A BIT OF A
COLD AIR DAMMING SITUATION WITH NE WINDS INLAND...AND A MORE E
FLOW NEAR THE COAST...WITH A COASTAL FRONT DEVELOPING. THIS
COMBINED WITH MID LVL WAA...WILL PRODUCE A STEADY RAIN BY
AFTERNOON ON THE COASTAL PLAIN AND INTO THE FOOTHILLS. IN THE MTNS
AND POINTS N...WILL BE MORE SHOWERY INTO THE AFTERNOON AS THE
DOWNSLOPE HELPS DRY THINGS A BIT...BUT EVEN HERE THE WAA WILL
PRODUCE STEADY RAIN BY LATE IN THE DAY. HIGHS WILL WORK THEIR WAY
INTO THE UPPER 40S N TO MIS 50S ON THE COAST...AS THE THE MARINE
AIR WORKS IN.

TUESDAY WILL SEE A MAINLY STEADY LIGHT RAIN CONTINUE OVERNIGHT AS
WARM/MOIST AIR ADVECTION CONTINUES. THE WINDS WILL GRADUALLY PICK
OVERNIGHT AS THE SFC LOW BEGIN TO FORM S OF LONG ISLAND NY...BUT
THE HEAVIEST RAIN AND BREEZIEST CONDITIONS WILL HOLD OFF UNTIL
WED.  MINS WILL DROP BACK INTO THE 40S TUE NIGHT.

&&

.LONG TERM /WEDNESDAY NIGHT THROUGH MONDAY/...
THE MODELS ARE IN GENERAL AGREEMENT ON THE LONG WAVE PATTERN
WELL INTO NEXT WEEK. WE BEGIN THE PERIOD WITH A CLOSED LOW NEAR
THE DELMARVA. THE UPPER LOW WILL SLOWLY MEANDER NORTHEAST ALONG
THE COASTLINE THROUGH FRIDAY NIGHT BEFORE EXITING INTO THE
MARITIMES ON SATURDAY. AT THE SURFACE...LOW PRESSURE WILL BE
SITUATED JUST OFFSHORE AND DRIFT SLOWLY NORTHEAST THROUGH THE MID
ATLANTIC AND NEW ENGLAND COASTAL WATERS WEDNESDAY THROUGH FRIDAY
BEFORE EXITING THE REGION BY SATURDAY. WE`LL SEE BANDS OF RAIN
PINWHEELING IN OFF THE ATLANTIC WEDNESDAY THROUGH FRIDAY...WITH
THE HEAVIEST RAIN LIKELY FALLING WEDNESDAY AND THURSDAY. QPF
AMOUNTS ON THE ORDER OF 2 TO 4 INCHES ARE LIKELY ACROSS THE
FORECAST AREA WITH LOCALIZED 5 INCH TOTALS POSSIBLE ACROSS THE
WESTERN MAINE MOUNTAINS. ON SATURDAY...SOME LINGERING CLOUDS AND
WIDELY SCATTERED SHOWERS MAINLY ACROSS THE HIGHER
TERRAIN...DESPITE WEAK RIDGING BEHIND THE UPPER LOW. MORE
UNSETTLED WEATHER FOR SATURDAY NIGHT AND SUNDAY AS A QUICK MOVING
SHORTWAVE DRIVES ANOTHER COLD FRONT ACROSS THE AREA. A RIDGE OF
HIGH PRESSURE FOLLOWS FOR MONDAY.

&&

.AVIATION /04Z TUESDAY THROUGH SATURDAY/...
SHORT TERM...VFR SHOULD HOLD THRU MUCH OF TONIGHT...WITH GRADUALLY
DETERIORATING CONDS BEGINNING TOWARD DAYBREAK AS ONSHORE FLOW
MOVES STRATUS AND RAIN INLAND ON WED...BY WED AFTERNOON SHOULD SEE
COASTAL AREAS DOWN TO IFR...WITH INLAND AREAS FOLLOWING BY TUE
EVENING.

LONG TERM...

WED - FRI...IFR IN RAIN AND FOG. NE SFC WND GUSTING TO 25 KT.

SAT...SCT MVFR PSBL IN SHOWERS.

&&

.MARINE...
SHORT TERM...WINDS/SEAS CONTINUE TO DIMINISH OVERNIGHT AND INTO
TUESDAY MORNING. WILL SEE E FLOW BEGIN TO PICK UP TUESDAY
AFTERNOON AND ESPECIALLY TUE NIGHT...WITH SCA SEAS/WINDS EXPECTED
BY MIDNIGHT...AND BUILDING TO GALES BY WED MORNING.

LONG TERM...

WED - THU...GALE FORCE WINDS ARE LIKELY.

FRI...SMALL CRAFT CONDITIONS ARE LIKELY.

&&

.HYDROLOGY...
MAIN STEM RIVERS WILL NEED TO BE MONITORED CLOSELY MID TO LATE WEEK.
MOST SMALL RIVERS AND STREAMS WILL LIKELY HAVE SHARP RISES AS
WELL. THE HEAVIEST RAINFALL IS EXPECTED TO BE OVER SOUTH-CENTRAL
MAINE AND THE NORTHEAST FACING HIGHER TERRAIN. AGAIN...MOSTLY 2-3 INCHES
QPF WITH LOCALIZED AMOUNTS APPROACHING 5 INCHES.

&&

.TIDES/COASTAL FLOODING...
COASTAL FLOODING IS A POSSIBILITY AS THE SYSTEM MAKES A LOOP OVER
LONG ISLAND NEW YORK ON THURSDAY. WAVE RUN UP TOOLS INDICATING
SOME BEACH EROSION AND SPLASH OVER ACROSS MUCH OF OUR
COASTLINE. NEAR SHORE WAVES COULD TOP OUT IN THE 10 TO 15 FOOT
RANGE.

&&

.GYX WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
NH...NONE.
MARINE...GALE WATCH FROM LATE TONIGHT THROUGH THURSDAY MORNING FOR
     ANZ150>154.

&&

$$
SYNOPSIS...
NEAR TERM...CURTIS
SHORT TERM...
LONG TERM...
AVIATION...
MARINE...
HYDROLOGY...
TIDES/COASTAL FLOODING...



USA.gov is the U.S. government's official web portal to all federal, state and local government web resources and services.