Area Forecast Discussion
Issued by NWS Portland, ME

Current Version | Previous Version | Graphics & Text | 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
-- Highlight Changed Discussion --
-- Discussion containing changed information from previous version are highlighted. --
000 FXUS61 KGYX 151253 AFDGYX AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE GRAY ME 853 AM EDT TUE APR 15 2014 .SYNOPSIS... A FRONTAL BOUNDARY NEARS FROM THE WEST TODAY AND SLOWLY CROSSES THE REGION LATE TONIGHT BEFORE MOVING OFFSHORE. GUSTY WINDS DEVELOP IN ITS WAKE WITH HIGH PRESSURE BUILDING IN BEHIND IT WEDNESDAY THROUGH FRIDAY. LOW PRESSURE PASSES OFFSHORE LATE SATURDAY...FOLLOWED BY HIGH PRESSURE FOR SATURDAY AND SUNDAY. && .NEAR TERM /UNTIL 6 PM THIS EVENING/...
-- Changed Discussion --
13Z UPDATE... ISSUING WIND ADVISORIES FOR COASTAL ZONES FOR THE AFTERNOON AND EVENING HOURS. STRONG LOW LEVEL JET FORECAST TO SHIFT INTO THE REGION AHEAD OF THE COLD FRONT. SOME QUESTION AS TO JUST HOW MUCH WILL MIX DOWN BUT ALREADY GUSTING TO NEAR 30 AND SHOULD NOT HAVE MUCH PROBLEM REACHING GUSTS TO 40 MPH LATER THIS AFTERNOON AND EVENING. PREVIOUS DISCUSSION... WATER VAPOR IMAGERY SHOWS A DEEP TROUGH CARVED OUT THROUGH THE CENTRAL CONUS WITH THE UPPER LOW CENTERED OVER ONTARIO. A COLD FRONT BISECTED THE COUNTRY BRINGING FREEZING TEMPERATURES AND SNOW TO EVEN THE DEEP SOUTH OVER THE NEXT 24 HOURS. IMPACTS FOR NEW ENGLAND WILL COME IN THE LIQUID FORM FOR THE MOST PART AS WARM MOIST AIR CONTINUES TO BE DRAWN NORTH AHEAD OF THE BOUNDARY AS IT MOVES SLOWLY TOWARDS NEW ENGLAND. CURRENTLY THE BOUNDARY WAS NEAR THE VERMONT/ NY STATE BORDER AND ORIENTED NNE TO SSW. LIGHT WARM ADVECTION SHOWERS WILL CONTINUE AND INCREASE IN COVERAGE AS THE MORNING WEARS ON WITH THE REAL RAIN NOT ARRIVING UNTIL THE AFTERNOON AND EVENING AS THE FRONT ITSELF CROSSES INTO NH AND THEN MAINE BY EARLY AFTERNOON. EXPECT THE PRECIPITATION TO INTENSIFY AS A VERY STRONG LOW LEVEL JET OF 55-65 KTS ACTS ON FRONTOGENESIS MAXIMUM. HEAVY RAIN WILL CONTINUE INTO TONIGHT TRIGGERING FLOODING ON AREA RIVERS. MORE ON THIS IN THE HYDROLOGY SECTION BELOW. DID NOT SEE ENOUGH SUPPORT TO INCLUDE THUNDER IN THE FORECAST. HIGH TEMPERATURES TODAY WILL RANGE FROM UPPER 50S TO UPPER 60S. SKIES ARE ALREADY BECOMING BROKEN TO OVERCAST AND ROBBING NEW ENGLANDERS OF A NICE LUNAR ECLIPSE. IN ADDITION SOUTHERLY WINDS WILL BE GUSTY ONCE AGAIN TODAY. INVERSION AT THE SURFACE SHOULD KEEP THE STRONGER WINDS FROM MIXING DOWN...BUT THIS WILL NEED TO BE REASSESSED FOR LATE TONIGHT INTO WEDNESDAY MORNING AS COLD AIR ADVECTION BEHIND THE FRONT MAY MIX STRONGER WINDS TO THE SURFACE... ESPECIALLY OVER THE MIDCOAST REGION.
-- End Changed Discussion --
&& .SHORT TERM /6 PM THIS EVENING THROUGH 6 PM WEDNESDAY/... AFTER MIDNIGHT TONIGHT...EXPECT RAIN TO CHANGE OVER TO SNOW BRIEFLY AND DROP BETWEEN A HALF INCH TO AROUND 2" OF SNOW OVER THE HIGHER TERRAIN AS THE COLD AIR CATCHES UP TO THE MOISTURE. OVERNIGHT LOWS WILL BE VARY WITH LOWER 20S IN THE MOUNTAINS AND FOOTHILLS...WHERE THE COLDER AIR WILL HAVE ALREADY BEGUN FILTERING IN BEHIND THE FRONT...AND LOWER TO MID 30S ELSEWHERE. WEDNESDAY THERE WILL BE A SIMILAR TEMPERATURE DISCREPANCY FOR HIGH TEMPERATURES... BUT GUSTY NW WINDS WILL MAKE IT SEEM CHILLY AREAWIDE. && .LONG TERM /WEDNESDAY NIGHT THROUGH MONDAY/... HIGH PRESSURE MOVES IN QUICKLY WEDNESDAY EVENING AND WILL BE OVER NORTHERN NEW ENGLAND BY THURSDAY MORNING. WITH COOL AND VERY DRY AIR IN PLACE... CALM WINDS... AND A LIKELY CLEAR SKY... TEMPERATURES WILL BE ABLE TO FALL OFF EASILY OVERNIGHT WEDNESDAY NIGHT AND WILL REACH THE TEENS AND 20S BY THURSDAY MORNING. RECORD LOW TEMPERATURE AT PORTLAND ON THURSDAY IS 24 DEGREES SET IN 2003. THE RECORD AT CONCORD IS 18 SET IN 1908. BOTH RECORDS ARE WITHIN REACH OF BEING TIED OR BROKEN. WITH EACH SUCCESSIVE MODEL RUN... GUIDANCE CONTINUES TO FORECAST COLDER TEMPERATURES. HOWEVER... IT IS WORTH NOTING THAT THE MODELS (AND THE MOS IN PARTICULAR) HAVE BEEN INCREDIBLY BAD WITH LOW TEMPERATURES THIS WINTER AND SPRING SO FAR. SO SOME SKEPTICISM OF EXTREME COLD MAY BE WARRANTED. FOR NOW THE FORECAST CALLS FOR TEMPERATURES FALLING TO NEAR THE RECORD LOWS AT BOTH LOCATIONS. HIGH PRESSURE SHIFTS INTO THE CANADIAN MARITIME PROVINCES ON THURSDAY... WITH THE RIDGE AXIS PERSISTING BACK TO THE SOUTHEAST THROUGH NEW ENGLAND AND DOWN THE EAST COAST. THIS WILL KEEP THE COOL AIR FLOWING FROM EAST TO WEST OFF THE COLD NORTH ATLANTIC. EXPECT HIGH TEMPERATURES ONLY IN THE 40S ON THURSDAY AND FRIDAY FOR MOST COASTAL AREAS. INLAND AREAS ESPECIALLY ON THE OTHER SIDE OF THE MOUNTAIN RANGES WILL RISE INTO THE 50S. ANOTHER MID/UPPER LEVEL TROUGH WILL MOVE ACROSS THE NORTHEASTERN UNITED STATES ON SATURDAY. MODELS ARE NOT SHOWING STRONG SURFACE FEATURES ASSOCIATED WITH THIS SYSTEM BUT RATHER A WEAK AND ILL DEFINED LOW TRACKING OFFSHORE. SOME SHOWERS ARE POSSIBLE AS THE TROUGH MOVES THROUGH BUT THE LACK OF ORGANIZATION WITH THIS SYSTEM SUGGESTS THAT PRECIPITATION AMOUNTS WILL BE LIGHT AND WILL MOSTLY FALL AS RAIN. HIGH PRESSURE BUILDS IN BEHIND THE LOW FOR SUNDAY AND MONDAY WITH TEMPERATURES NEAR SEASONAL NORMALS. && .AVIATION /13Z TUESDAY THROUGH SATURDAY/... SHORT TERM...TAF SITES ARE GENERALLY MVFR AT THE MOMENT AND WILL DROP PRECIPITOUSLY ESPECIALLY AFTER 12Z AS RAIN BEGINS. HEAVY RAIN SHOULD START BETWEEN 17 AND 20Z AND BRING MOST TERMINALS TO IFR FOR SEVERAL HOURS. SOME IMPROVEMENT TO LIFR AROUND 16/4-6Z. LONG TERM...SHOULD SEE VFR CONDITIONS AFTER THE FRONT MOVES THROUGH EARLY WEDNESDAY. AN EASTERLY ONSHORE FLOW FROM THURSDAY THROUGH SATURDAY COULD PROVIDE SOME LOW LEVEL CLOUDS OR EVEN SOME FOG ESPECIALLY AT COASTAL LOCATIONS. && .MARINE... SHORT TERM...GALE WARNINGS REMAIN IN EFFECT THROUGH NOON WEDNESDAY AS A STRONG COLD FRONT CROSSES THE WATERS. LONG TERM...HIGH PRESSURE BUILDS IN WEDNESDAY WITH WINDS SUBSIDING. A PERSISTENT EASTERLY FLOW DEVELOPS ON THURSDAY THROUGH SATURDAY AS AN AXIS OF HIGH PRESSURE REMAINS OVER NEW ENGLAND AND THE CANADIAN MARITIMES. && .GYX WATCHES/WARNINGS/ADVISORIES...
-- Changed Discussion --
ME...FLOOD WATCH THROUGH WEDNESDAY EVENING FOR MEZ007>009-012>014- 018>028. WIND ADVISORY FROM 4 PM THIS AFTERNOON TO 2 AM EDT WEDNESDAY FOR MEZ022>028. NH...FLOOD WATCH THROUGH WEDNESDAY EVENING FOR NHZ001>010-013-014. WIND ADVISORY FROM 4 PM THIS AFTERNOON TO 2 AM EDT WEDNESDAY FOR NHZ014. MARINE...GALE WARNING UNTIL NOON EDT WEDNESDAY FOR ANZ150>154.
-- End Changed Discussion --
&& $$

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