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AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAY ME
1120 AM EDT SUN MAY 3 2015

.SYNOPSIS...
HIGH PRESSURE OFFSHORE WILL BRING A SOUTHERLY FLOW OVER THE
NORTHEAST AND TRANSPORT WARMER AIR INTO THE AREA. SOME AFTERNOON
SHOWERS OR A THUNDERSTORM ARE POSSIBLE TODAY. A WEAK COLD FRONT
WILL CROSS THE AREA MONDAY NIGHT AND EARLY TUESDAY WITH SCATTERED
SHOWERS AND THUNDERSTORMS. ANOTHER MOISTURE STARVED COLD FRONT
WILL CROSS THE AREA WEDNESDAY. A RIDGE OF HIGH PRESSURE FOLLOWS
FOR LATE WEDNESDAY INTO FRIDAY. A DEVELOPING ONSHORE FLOW AND AN
APPROACHING WARM FRONT WILL MAKE THE WEATHER INCREASINGLY
UNSETTLED FOR THE UPCOMING WEEKEND.

&&

.NEAR TERM /TODAY/... 
1130 AM UPDATE...
TEMPERATURES ARE WARMING UP A BIT MORE QUICKLY THAN FORECAST SO
THIS IS NOW REFLECTED IN THE LATEST UPDATE. HAVE INCREASED
AFTERNOON HIGH TEMPERATURES IN THE NORTH AND WEST... BASICALLY
MOST INLAND AREAS. ALONG THE COAST FROM PORTLAND EASTWARD
TEMPERATURES ARE SLOWER TO REACT AFTER MORNING CLOUDS FINALLY
DISAPPEARED. TEMPERATURES HAVE BEEN LOWERED ALONG THE IMMEDIATE
COAST AS IT WILL BE TOUGH TO GET MUCH WARMING TODAY WITH AN
ONSHORE FLOW AS NOTED BY YESTERDAY'S COLDER THAN FORECAST HIGHS.
MID LEVEL SHORTWAVE TROUGH NOW MOVING INTO THE AREA AS NOTED BY
A COUPLE BANDS OF CLOUDS AND LIGHT SHOWERS. ADDITIONAL CUMULUS IS
FORMING BENEATH THIS AREA ALONG THE HIGHER TERRAIN AND WILL LIKELY
RESULT IN SHOWERS WITHIN THE NEXT FEW HOURS.

830 AM UPDATE...
HAVE UPDATED THE FORECAST PRIMARILY TO ADJUST PRECIPITATION
CHANCES THIS AFTERNOON. FIRST LOOK AT THE MORNING SOUNDING
SUGGESTS THAT ONCE TEMPERATURES REACH THE UPPER 60S THERE WILL BE
ENOUGH INSTABILITY FOR SOME SHOWERS. THESE WILL BE TIED TO THE
TERRAIN INITIALLY BEFORE DRIFTING OFF THE TERRAIN AND DISSIPATING.
THEREFORE HIGHEST CHANCES FOR RAIN WILL BE OVER THE TERRAIN AREAS
AND THE GRIDDED FORECAST NOW REFLECTS THIS. CANNOT RULE OUT SOME
GRAUPEL WITH SHOWERS THIS AFTERNOON BUT BASED ON THE LOCATION OF
INSTABILITY WITH REGARDS TO ATMOSPHERIC TEMPERATURE PROFILE IT
SEEMS LESS LIKELY. MORNING CLOUDS AND FOG OVER THE MAINE COAST
SHOULD DISSIPATE OVER THE NEXT HOUR OR TWO AT MOST.

620 AM...
APPARENTLY...THE COASTAL FOG AND STRATUS HAD A SECOND WIND AND
HAVE MOVED BACK TO THE N AND W...AT LEAST AS FAR AS KWVL-KIZG-
KPSM. HARD TO FIND OBSERVATIONS THAT WOULD SUGGEST MUCH TOO FAR N
AND W OF THERE. HAVE ADJUSTED GRIDS ACCORDINGLY...AND STILL EXPECT
IT DISSIPATE BETWEEN 12 AND 14Z.

ORIGINAL DISCUSSION...
COASTAL STRATUS AND FOG HAVING A TOUGHER TIME HOLDING TOGETHER
THIS MORNING THAN YESTERDAY...GIVEN INCREASING FLOW AND STEEPER
LAPSE RATES ABOVE THE BOUNDARY LAYER...AND IT SHOULD DISSIPATE
FAIRLY QUICKLY AFTER SUNRISE.

FOR TODAY...WILL SEE WEAK 500 MB WAVE MOVING THRU THE 500MB
RIDGING ALOFT...WHICH WILL ALLOW FOR SOME HEIGHT FALLS THIS
MORNING AND PRODUCE SOME DECENT LOW LEVEL LAPSE RATES AWAY FROM
THE COAST THIS AFTERNOON. DYNAMIC FORCING NOT IMPRESSIVE...BUT
THERE WILL BE SOME CONVERGENCE GENERATED BY WEAK LEE TROUGH...AND
ENOUGH INSTABILITY TO PROBABLY GET A BOOST FROM LOW LEVEL
LIFT...EITHER DUE TO TERRAIN...OR ALONG INLAND SIDE OF SEA BREEZE
BOUNDARY. DEPENDING ON WHICH WHICH MESOSCALE MODEL YOU LOOK
AT...INCLUDING RAP/WRF/NAMDNG/CMC 2.5KM...SCATTERED CONVECTION
POPS UP IN EITHER OF THESE SPOTS AROUND 18-21Z...WITH A SLIGHT
SKEW TOWARD THE MOUNTAINS AND FOOTHILLS OF WESTERN MAINE. WOULD
EXPECT SOME SCATTERED SHOWERS...ISOLATED THUNDERSTORMS THIS
AFTERNOON AWAY FROM THE COAST...AS THE STABLE MARINE LAYER IS
LIKELY TO QUICKLY DESTROY ANY CONVECTION THAT MOVES INTO IT.
WOULD NOT BE SURPRISED TO SEE A REPORT OR TWO OF GRAUPEL/SMALL
HAIL GIVEN COLDER AIR ALOFT. AGAIN THE SEA BREEZE KEEPS THE
IMMEDIATE COAST ABOUT 10 F COOLER FOR HIGHS TODAY...UPPER 50S TO
LOW 60S...WHERE INLAND SPOTS WILL REACH TO 70-75.

&&

.SHORT TERM /TONIGHT AND MONDAY/... 
ANY SHOWERS WILL DIMINISH QUICKLY WITH THE SETTING SUN AND SKIES
SHOULD BECOME MAINLY CLEAR. COULD SEE ANOTHER ROUND OF COASTAL
STRATUS AND FOG AGAIN...ALTHOUGH PROBABLY LESS LIKELY GIVEN
INCREASING SW FLOW...BUT IF THE STRATUS SITS JUST OFFSHORE THRU
THE DAY...IT IS LIKELY TO CREEP IN AFTER SUNSET. MINS WILL
GENERALLY BE FROM AROUND 40 INTO THE MID 40S.

MONDAY LOOKS TO BE WARM AND GENERALLY SUNNY AS GRADIENT SW FLOW
DEVELOPS. HIGHS IN THE MID 70S TO LOW 80S AT ALL BUT THE
IMMEDIATE SHORELINE....WHERE IT WILL STAY IN THE 60S. ANY
PRECIPITATION FROM APPROACHING COLD FRONT WILL HOLD OFF UNTIL
AFTER SUNSET.

&&

.LONG TERM /MONDAY NIGHT THROUGH SATURDAY/...
A COLD FRONT MOVES ACROSS THE REGION MONDAY NIGHT AND EARLY
TUESDAY...SCATTERED SHOWERS AND THUNDERSTORMS WILL BE ASSOCIATED
WITH THE FRONT. BY MID MORNING TUESDAY THE FRONT MOVES WELL SOUTHEAST
OF THE AREA WITH HIGH PRESSURE TO BUILD IN FROM THE GREAT LAKES.
CLEARING WILL BE EXPECTED FROM NORTH TO SOUTH TUESDAY WITH
CONTINUED MILD TEMPERATURES AS VERY LITTLE IN THE WAY OF COOL AIR
MAKES ITS WAY SOUTH BEHIND THE FRONT. HIGH PRESSURE WILL BRING
SUNNY SKIES WEDNESDAY AND AGAIN THURSDAY WITH TEMPERATURES NEAR
70 EXCEPT 60S IN THE MOUNTAINS. BY FRIDAY CLOUDS SPILL ACROSS THE
UPPER RIDGE AXIS OVER THE NORTHEAST...THIS WILL BE DUE TO AN
APPROACHING WARM FRONT FROM THE WEST. MODELS SHOW UNSETTLED
WEATHER TO DEVELOP OVER THE WEEKEND WITH A WARMER AND MOIST
UNSTABLE SOUTHWEST FLOW. IT LOOKS LIKE SPRING HAS FINALLY SPRUNG!

&&

.AVIATION /13Z SUNDAY THROUGH THURSDAY/...
SHORT TERM...THE COASTAL STRATUS DISSIPATES QUICKLY AFTER SUNRISE
TODAY WITH VFR INTO THE EVENING. AN ISOLATED SHOWER OR EVEN A
THUNDERSTORM IS POSSIBLE AWAY FROM THE COAST...BUT BEST CHANCE
WILL BE AT KHIE...AND MAYBE KLEB.

LONG TERM...MONDAY NIGHT INTO TUESDAY MORNING SCATTERED MVFR
CONDITIONS POSSIBLE IN SHOWERS AND ANY THUNDERSTORMS...OTHERWISE
VFR CONDITIONS THE REST OF THE OUTLOOK PERIOD.

&&

.MARINE...
SHORT TERM...SW WINDS PICK UP DURING THE DAY AND COULD APPROACH
SCA IN THE AFTERNOON.  

LONG TERM...MONDAY NIGHT...SMALL CRAFT WINDS AND SEAS ARE
POSSIBLE OVER THE OUTER WATERS. OTHERWISE WINDS AND SEAS WILL
REMAIN BELOW SCA CONDITIONS THROUGH THE OUTLOOK PERIOD.

&&

.FIRE WEATHER...
AFTERNOON HUMIDITY LEVELS DROP TO 35-45 PERCENT TODAY BUT WINDS
WILL REMAIN LIGHT...WITH GOOD RH RECOVERY TONIGHT. MONDAY WILL SEE
30-40 PERCENT MIN RH VALUES WITH SLIGHTLY STRONGER WINDS...10-15
MPH...BUT ARE EXPECTED TO REMAIN BELOW RED FLAG CRITERIA. GOOD
RECOVERY IS EXPECTED MONDAY NIGHT...WITH SCATTERED SHOWERS.

&&

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

&&

$$

NEAR TERM UPDATE... KIMBLE

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