FXUS61 KGYX 200717
AFDGYX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAY ME
317 AM EDT SAT SEP 20 2008
.SYNOPSIS...
A RIDGE OF HIGH PRESSURE WILL REMAIN OVER THE REGION TODAY...THEN
WEAKEN TONIGHT AS A COLD FRONT APPROACHES FROM THE NORTHWEST. THE
FRONT WILL CROSS THE REGION LATE TONIGHT AND SUNDAY. HIGH PRESSURE
WILL BUILD IN BEHIND THE FRONT THROUGH THE MIDDLE OF NEXT WEEK. 
&&
.NEAR TERM /THROUGH TODAY/...
MOISTURE BEING ADVECTED NORTHWARD FROM THE GULF OF MAINE HAS
BROUGHT SOME CLOUDS INTO COASTAL AREAS THIS MORNING. THESE SHOULD
BURN OFF LATER THIS MORNING WITH MOSTLY SUNNY SKIES ACROSS THE
REGION. ELSEWHERE...ANY VALLEY FOG SHOULD BURN OFF BY ABOUT 9 AM.
HIGH TEMPERATURES TODAY WILL BE MAINLY IN THE 60S ACROSS THE
REGION.
&&
.SHORT TERM /TONIGHT/...
A COLD FRONT WILL MOVE INTO THE MOUNTAINS FROM THE NORTHWEST LATE
TONIGHT. AHEAD OF THE FRONT...CLOUDINESS SHOULD BE ON THE
INCREASE. HOWEVER...THE FRONT IS NOT EXPECTED TO PRODUCE ANY
PRECIPITATION OVERNIGHT...BUT CAN'T RULE OUT A SPRINKLE.
TONIGHT...WITH CLEAR SKIES THIS EVENING...TEMPERATURES WILL DROP
OFF QUICKLY AFTER SUNSET. ONCE AGAIN...VALLEY FOG WILL FORM IN
THE FAVORED VALLEYS...ESPECIALLY IN SOUTHERN AREAS WHERE CLOUDS
FROM THE APPROACHING FRONT WILL ARRIVE LATE.
&&
.LONG TERM /SUNDAY THROUGH FRIDAY/...
THE COLD FRONT SHOULD PASS THROUGH THE FORECAST AREA SUNDAY
MORNING WITH LITTLE IN THE WAY OF INITIAL FANFARE. COULD SEE SOME
SHOWERS IN THE UPSLOPE LOCATIONS SUNDAY MORNING. WITH THE MID
LEVEL SUPPORT FOR THE FRONT SHEARING OUT TO THE NORTHEAST SUNDAY
MORNING...IT APPEARS AS THOUGH THE FRONT MAY STALL NEAR THE
SOUTHERN PORTION OF THE AREA SUNDAY AFTERNOON. 
MODELS INDICATE THAT THERE WILL BE SOME DEW POINT POOLING AS THE
LOCAL WIND FIELD BENDS TO CONFORM TO THE NEWLY STALLED FRONT.
WHETHER THIS WILL BE ENOUGH SURFACE CONVERGENCE WITH THE AVAILABLE
MOISTURE FOR SHOWER DEVELOPMENT IS PROBLEMATIC. MODIFIED MODEL
SOUNDINGS SHOW THE POTENTIAL FOR SHALLOW CONVECTION NEAR THE FRONT
IN SOUTHEAST NEW HAMPSHIRE AND YORK COUNTY MAINE. WITH RELATIVELY
LOW SURFACE DEW POINTS...DEEPER CONVECTION APPEARS UNLIKELY.
IN ANY EVENT...WILL HOLD OFF MENTIONING THE SHOWER POTENTIAL IN
THE TEXT FORECAST FOR NOW...AND CONTINUE THE SLIGHT CHANCE MENTION
IN THE GRIDDED FORECAST SUNDAY AFTERNOON. AT THIS POINT...IT APPEARS
AS THOUGH THE MOST IN THE WAY OF CLOUDS WILL BE NEAR THE FRONT...AND
ALL ZONES WERE ASSIGNED PARTLY SUNNY FOR NOW. IF IT DOES APPEAR AS
THOUGH THE FRONT WILL REMAIN STATIONARY IN THE SOUTHERN PORTION OF
THE FORECAST AREA...THIS REGION COULD END UP MOSTLY CLOUDY. HIGHS
SUNDAY WERE BASED ON A MOS BLEND...AND THIS COULD BE HIGHLY
INFLUENCED BY CLOUD COVER.
THE FRONT REMAINS MORE OR LESS IN PLACE ACROSS THE SOUTHERN ZONES
SUNDAY NIGHT. AS THE MID LEVEL FLOW REMAINS BROADLY CYCLONIC...
THERE DOES NOT APPEAR TO BE ANY FORCING UPSTREAM TO KICK THE FRONT
SOUTH. BASED ON THIS...CLOUDS AND A SLIGHT CHANCE OF SHOWERS WERE
PLACED IN THE FORECAST FOR SOUTHERN ZONES. THE GFS MOS NUMBERS
SEEM TOO LOW BASED CLOUDS IN THE SOUTH...AND A BLEND WAS USED
HERE. ELSEWHERE...THE GFS MOS WAS USED AS A TEMPLATE FOR LOWS.
NOT MUCH IN THE WAY OF CHANGE EXPECTED MONDAY. THUS...THE MOST IN
THE WAY OF CLOUDS AND A SLIGHT CHANCE OF SHOWERS WAS PLACED IN THE
FAR SOUTHERN PORTION OF THE AREA. THIS IS BASED ON CONTINUITY...AND
LATER FORECASTS MAY BE BETTER ABLE TO DETERMINE IF THE THREAT IS
GREATER. HIGHS WERE BASED ON A MOS BLEND.
A SHORT WAVE IN THE NORTHERN STREAM DROPS INTO THE MEAN TROUGH
POSITION WELL EAST OF THE AREA MONDAY NIGHT. THIS SHOULD BE ENOUGH
FORCING TO FINALLY KICK THE STATIONARY FRONT SOUTH...AND THERE IS
A SURFACE REFLECTION WITH THE SHORT WAVE AS WELL. THIS IS BEST
SEEN IN THE SURFACE DEW POINT FIELD. NOT SURE THERE WILL BE ANY
SHOWER ACTIVITY WITH THIS FRONT...AS THE COLD AIR ADVECTION
APPEARS SHALLOW. IT APPEARS AS THOUGH THE FRONTAL PASSAGE MAY BE
TOO LATE FOR A FROST OR FREEZE FOR THE SOUTHERN ZONES.
AFTER THIS...THE BROADLY CYCLONIC FLOW IN THE MID LEVELS BACK TO A
FLAT RIDGE...THEN A MEAN RIDGE POSITION THROUGH THE MIDDLE OF NEXT
WEEK. WITH SURFACE HIGH PRESSURE IN PLACE...THIS SHOULD BE A DRY
AND SEASONABLY COOL PERIOD. NO CHANGES WERE MADE TO THE END OF THE
FORECAST PERIOD AS TIMING AND PLACEMENT ISSUES FOR MASS FIELDS
CONTINUES.
&&
.AVIATION /06Z SATURDAY THROUGH WEDNESDAY/...
IN THE SHORT TERM...VALLEY FOG WILL AFFECT SHELTERED VALLEYS
EARLY THIS MORNING AND AGAIN LATER TONIGHT CAUSING LIFR TO IFR
CONDITIONS. IN COASTAL AREAS...A CLOUD LAYER AT ABOUT 3000 FT WILL
AFFECT THE IMMEDIATE COAST FOR SEVERAL HOURS THIS MORNING...BUT WILL
BURN OFF LATER THIS MORNING.  OTHERWISE VFR CONDITIONS ARE EXPECTED.
IN THE LONG TERM...MAY SEEM SOME MVFR CONDITIONS WITH THE PASSAGE
OF THE COLD FRONT...ESPECIALLY AT KLEB IN THE LATE MORNING AND
AFTERNOON. AFTER THIS...DEPENDING ON WHERE THE FRONT COMES TO REST
SUNDAY EVENING AND MONDAY...COULD BE SOME MVFR CEILINGS AT KPSM
AND KCON. COULD ALSO BE SOME RADIATIONAL FOG AT KLEB BETWEEN 0800
AND 1300 UTC MONDAY...AGAIN DEPENDING ON THE POSITION OF THE FRONT
WHEN IT STALLS.
AFTER THIS...WOULD EXPECT LOCAL LIFR CONDITIONS LATE AT NIGHT AND
VFR CONDITIONS ELSEWHERE MONDAY THROUGH WEDNESDAY.
&
.MARINE...
IN THE SHORT TERM...WINDS AND SEAS WILL REMAIN BELOW SMALL CRAFT
CRITERIA AS A RIDGE OF HIGH PRESSURE CRESTS OVER THE WATERS.
IN THE LONGER TERM...WINDS COULD GUST TO NEAR 20 KNOTS ON THE
OCEAN WATERS WITH THE PASSAGE OF THE FRONT...ESPECIALLY NORTHEAST
OF PORTLAND. A SECONDARY COLD FRONT CROSSING THE WATERS MONDAY
NIGHT COULD HAVE SOME GUSTINESS AS WELL...BUT IT APPEARS AS THOUGH
WINDS WILL REMAIN BELOW 20 KNOTS. SEAS ARE EXPECTED TO REMAIN
BELOW 5 FEET THROUGH THE PERIOD.
&&
.GYX WATCHES/WARNINGS/ADVISORIES...
ME...FROST ADVISORY UNTIL 8 AM EDT THIS MORNING FOR MEZ018>022.
NH...FROST ADVISORY UNTIL 8 AM EDT THIS MORNING FOR NHZ005>010-013.
MARINE...NONE.
&&
$$
NEAR TERM...JENSENIUS 
SHORT TERM...JENSENIUS