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 020817
AFDGYX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAY ME
417 AM EDT MON MAY 2 2016

.SYNOPSIS...
AS ONE AREA OF RAIN DEPARTS THE AREA EARLY THIS MORNING ANOTHER
WILL FOLLOW ON ITS HEELS FOR THIS AFTERNOON. THE UNSETTLED WEATHER
WILL TRY AND STAY SOUTH OF THE AREA TUESDAY...BEFORE RETURNING
AGAIN FOR LATE IN THE WEEK. AN UPPER LEVEL LOW PRESSURE SYSTEM
LOOKS TO SETTLE INTO THE MID ATLANTIC INTO THE WEEKEND. THIS WILL
PROVIDE A FEW DAYS OF COOLER...ONSHORE FLOW AND SHOWERY WEATHER.

&&

.NEAR TERM /TODAY/...
THE FORECAST FOR THE NEXT SEVERAL DAYS WILL FEATURE SEVERAL
SHORTWAVE TROUGHS CROSSING THE AREA... EACH ONE A LITTLE FURTHER
SOUTH IN ITS TRACK THAN THE LAST.

THE FIRST IN A SERIES OF SHORTWAVE TROUGHS IS EXITING TO THE EAST
EARLY THIS MORNING... BUT THE NEXT ONE IS ALREADY APPROACHING FROM
THE WEST. SO WHILE SHOWERY WEATHER WILL LIKELY DIMINISH FOR A FEW
HOURS EARLY THIS MORNING... ANOTHER ROUND OF RAIN IS EXPECTED TO
ARRIVE FROM WEST TO EAST LATE THIS MORNING AND THROUGH THE
AFTERNOON. IN ADDITION... A PERSISTENT EAST/SOUTHEAST LOW LEVEL
FLOW WILL CONTINUE TO ADVECT MOISTURE IN OFF THE GULF OF MAINE
LEADING TO AREAS OF FOG AND DRIZZLE THROUGH THE MORNING.
TEMPERATURES TODAY WILL BE COOL WITH THE ONSHORE FLOW...CLOUD
COVER... AND RAIN. WENT A LITTLE BIT BELOW MOST OF THE FORECAST
MODEL GUIDANCE FOR TEMPERATURES THIS AFTERNOON AS IT WILL BE VERY
DIFFICULT FOR MOST OF US TO GET OUT OF THE 40S.

&&

.SHORT TERM /TONIGHT THROUGH TUESDAY/...
THE SHORTWAVE TROUGH AND ASSOCIATED WEAK SURFACE LOWS WILL MOVE
EASTWARD TONIGHT... TAKING THE STEADIER RAIN WITH IT. HIGH
PRESSURE BRIEFLY BUILDS IN BEHIND IT BUT ANOTHER TROUGH WILL BE
MOVING TOWARD THE AREA FROM THE SOUTHWEST BY TUESDAY MORNING. THIS
ONE WILL BE FAR ENOUGH SOUTH THAT ONLY SOUTHERN NEW HAMPSHIRE AND
PERHAPS COASTAL MAINE ARE AFFECTED WITH SOME LIGHT RAIN. BUT IT
WILL HELP TO KEEP AN EASTERLY FLOW OVER THE GULF OF MAINE AND INTO
NORTHERN NEW ENGLAND... KEEPING TEMPERATURES COOL ONCE AGAIN. RAW
MODEL OUTPUT HAS TEMPERATURES ONLY IN THE UPPER 40S TUESDAY WHILE
MOST OF THE MOS TRIES TO WARM THINGS UP MORE. DECIDED TO GO CLOSER
TO THE RAW MODEL OUTPUT GIVEN THE ONSHORE FLOW AND CLOUD COVER.
HOWEVER... ON THE OTHER SIDE OF THE MOUNTAINS TEMPERATURES COULD
WARM INTO THE 60S.

&&

.LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/...
THE EXTENDED FORECAST LOOKS A BIT LIKE A PUBLIC SERVICE
ANNOUNCEMENT FOR THE DANGERS OF SPRING IN NEW ENGLAND.
DETERMINISTIC AND ENSEMBLE MODEL GUIDANCE ARE CONSISTENT WITH THE
DEEPENING OF AN ERN CONUS TROF...WITH EVENTUAL CUT OFF LOW
FORMATION TO OUR SW.

A LEAST A FEW DAYS OF MOIST ONSHORE FLOW...AND SHOWERY WX ARE
LOOKING MORE LIKELY. FAVORED BLENDING IN A LITTLE MORE RAW MODEL
GUIDANCE TO THE MULTI-MODEL CONSENSUS...AS MOS RELATED PRODUCTS
ARE LIKELY BRINGING TEMPS UP TOO MUCH GIVEN THE EXPECTED CLOUD
COVER AND PRECIP IN THE AREA. AT THE SAME TIME...POP IS DIFFICULT
TO NAIL DOWN...AS NO ONE PERIOD IS LOOKING MORE OR LESS LIKELY FOR
RNFL AT THIS TIME. IT DOES APPEAR THAT A STRONGER S/WV MAY TRY AND
PASS THE AREA THU...BUT PROXIMITY OF THE UPPER LOW MAY ALSO FAVOR
DIURNAL INCREASES IN SHOWERS WITH COLD TEMPS ALOFT.

THE RELATIVELY LOWER HEIGHTS ALOFT LOOK TO CONTINUE INTO EARLY
NEXT WEEK...EVEN IF THE UPPER LOW LIFTS OUT. THE TREND OF COOLER
THAN NORMAL HIGH TEMPS AND ABOVE NORMAL CHANCES FOR PRECIP SHOULD
CONTINUE FOR THE FIRST WEEK OF MAY...SO THE CALENDAR MAY HAVE
CHANGED MONTHS BUT IT DOESN/T LOOK LIKE THE WX PATTERN HAS.

&&

.AVIATION /07Z MONDAY THROUGH FRIDAY/...
SHORT TERM...AREAS OF FOG AND DRIZZLE WILL KEEP CONDITIONS IFR OR
WORSE THROUGH THE MORNING. THEN THE RAIN MOVES IN LATE MORNING
THROUGH THE AFTERNOON WITH CONTINUED IFR CONDITIONS. MAY SEE A
BRIEF BREAK IN THE CLOUDS THIS EVENING AS THE LOW MOVES OUT... BUT
WITH ALL THE RAIN THAT FALLS TODAY ANY CLEARING WILL JUST BE
GROUNDS TO CAUSE FOG TO FORM AGAIN WITH NOCTURNAL COOLING IN THE
MOIST SURFACE AIR.

LONG TERM...UNDER THE INFLUENCE OF AN UPPER LOW PRES
SYSTEM...CLOUDS AND SHRA WILL REMAIN IN THE FORECAST THRU THE END
OF THE WEEK. AREAS OF MVFR AND LOCAL IFR WILL BE POSSIBLE IN
SHRA...AS WELL AS ANY MARINE FOG AND STRATUS.

&&

.MARINE...
SHORT TERM...ALTHOUGH WINDS REMAIN RELATIVELY LIGHT TODAY... AN
INCREASING EASTERLY FLOW TO THE NORTH OF DEVELOPING LOW PRESSURE
OFFSHORE WILL BEGIN GENERATING WAVES WHICH WILL HEAD WESTWARD INTO
THE GULF OF MAINE THIS EVENING. WAVE HEIGHTS ARE EXPECTED TO BE
AROUND 5 FEET SO A SMALL CRAFT ADVISORY FOR SEAS HAS BEEN ISSUED
THIS EVENING.

LONG TERM...A PERSISTENT AREA OF LOW PRES TO OUR S WILL BRING NE
FLOW ON THE WATERS INTO THE WEEKEND. WHILE WINDS LOOK TO REMAIN
BELOW SCA THRESHOLDS...LONG DURATION NE FLOW MAY BUILD SEAS
OUTSIDE THE BAYS TO NEAR 5 FT LATE IN THE WEEK.

&&

.FIRE WEATHER...
WEATHER PATTERN THIS WEEK WILL BE PRETTY CONSISTENTLY MOIST WITH
AN ONSHORE FLOW AND MULTIPLE OPPORTUNITIES FOR RAINFALL.

&&

.TIDES/COASTAL FLOODING...
BEGINNING THURSDAY THROUGH THE WEEKEND...WE ARE SET FOR A PERIOD
OF HIGH ASTRONOMICAL TIDES. THE HIGHEST TIDES WILL BE FRIDAY AND
SATURDAY NIGHTS WHEN PORTLAND IS FORECAST TO REACH 11.9 FEET AT
1135 PM AND 1226 AM RESPECTIVELY. COASTAL FLOODING MAY BE POSSIBLE
DURING THIS TIME PERIOD...AS WINDS WILL GENERALLY BE EASTERLY TO
NORTHEASTERLY. IF LOW PRESSURE DEVELOPS A LITTLE SOONER OR
STRONGER...COASTAL FLOODING ISSUES COULD BEGIN AS EARLY AS THE
THURSDAY EVENING TIDE.

&&

.GYX WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
NH...NONE.
MARINE...SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS FROM 4 PM THIS
     AFTERNOON TO 6 AM EDT TUESDAY FOR ANZ150-152-154.

&&

$$

NEAR TERM...KIMBLE
SHORT TERM...KIMBLE
LONG TERM...LEGRO
AVIATION...KIMBLE/LEGRO
MARINE...KIMBLE/LEGRO
FIRE WEATHER...KIMBLE
TIDES/COASTAL FLOODING...LEGRO



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