Area Forecast Discussion
Issued by NWS Portland, ME

Current Version | Previous Version | Text Only | Print | Product List | Glossary Off
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 300709 AFDGYX AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE GRAY ME 309 AM EDT TUE SEP 30 2014 .SYNOPSIS...
-- Changed Discussion --
SURFACE HIGH PRESSURE WILL HOLD OVER NORTHERN NEW ENGLAND THROUGH FRIDAY. HOWEVER...A MOIST NORTHEAST FLOW WILL KEEP CLOUDS AND A CHANCE OF SHOWERS AROUND INTO MIDWEEK. A COLD FRONT CROSSES THE REGION SATURDAY WITH LOW PRESSURE DEVELOPING ALONG IT. WEAK HIGH PRESSURE FOLLOWS IN THE WAKE OF THE LOW SUNDAY AND MONDAY.
-- End Changed Discussion --
&& .NEAR TERM /THROUGH TODAY/...
-- Changed Discussion --
SURFACE HIGH PRESSURE RIDGING WILL HOLD OVER THE REGION TODAY. HOWEVER...IT WILL COME WITH CONTINUED MOIST NORTHEAST FLOW. THIS WILL MEAN CLOUDS AND PERHAPS A FEW SHOWERS. AREAS OF DRIZZLE AND FOG SHOULD BE COMMON THIS MORNING. THEREFORE...TEMPERATURES ARE EXPECTED TO HOLD MAINLY IN THE 50S TODAY. AN EXCEPTION WILL LIKELY BE THE CT RIVER VALLEY WHERE THE LOW LEVEL COOL AIRMASS WILL BE SHALLOWER AND BE SUBJECT TO DOWNSLOPING. THEREFORE...HAVE TEMPERATURES RISING WELL INTO THE 60S THERE. OVERALL...WE EXPECT TODAY TO BE MOSTLY DRY BUT CLOUDY AND COOL.
-- End Changed Discussion --
&& .SHORT TERM /TONIGHT THROUGH 6 PM WEDNESDAY/...
-- Changed Discussion --
DURING TONIGHT AND WEDNESDAY...UPPER LEVEL LOW PRESSURE WILL MOVE FROM WESTERN PA TO OVER SOUTHERN NEW ENGLAND. THIS SHOULD ALLOW FOR ENHANCED EASTERLY INFLOW IN THE COLUMN AND WILL AID IN THE MAINTENANCE OF CLOUDS. THERE IS SOME QUESTION ABOUT HOW FAR NORTH THE BEST FORCING FOR ASCENT WILL GET. THE 00Z ECMWF IS THE MOST BULLISH MODEL IN THAT REGARD...WITH A STEADY MEASURABLE RAIN OVERSPREADING MUCH OF THE AREA /HEAVIEST SOUTHERN ZONES/ LATE TONIGHT AND ESPECIALLY WEDNESDAY. THE OTHER MEMBERS OF THE 00Z MODEL SUITE ARE MUCH MORE TAME. NEVERTHELESS...INCREASING MOIST EASTERLY INFLOW IN THE COLUMN SHOULD AID IN THE DEVELOPMENT OF SHOWERS LATE TONIGHT AND WEDNESDAY...AND HAVE COVERED THIS POSSIBILITY WITH CHANCE POPS FOR NOW.
-- End Changed Discussion --
&& .LONG TERM /WEDNESDAY NIGHT THROUGH MONDAY/...
-- Changed Discussion --
UPPER LOW PRES IS GRADUALLY KICKED EWD BY HIGH PRES BUILDING INTO THE AREA THU. THIS WILL BRING ABOUT A SLOW CLEARING AS DRIER AIR IS ADVECTED INTO THE REGION. THIS IS JUST A TEMPORARY CHANGE HOWEVER...AS WRN TROF MIGRATES EWD. SFC LOW PRES WILL RUN UP THRU THE GREAT LAKES...DRIVING A COLD FNT TOWARDS NEW ENGLAND. THIS WILL BE A SEASONABLY STRONG TROF...WITH AMPLE MOISTURE ON DEEP SLY FLOW...SO EXPECT A NARROW BUT POTENTIALLY HEAVY LINE OF SHOWERS/RNFL. MOST OF SAT SHOULD BE INCREASING LOW CLOUD COVER...WITH PCPN HOLDING OFF UNTIL AFTER MIDDAY ACROSS NH AND CLOSER TO 00Z FOR WRN ME. HAVE SPLIT THE FIRST HALF OF SAT INTO 6 HOUR POP GRIDS TO SLOW THE TIMING OF PCPN INTO THE FORECAST AREA. OTHERWISE...MODEL GUIDANCE IS IN FAIR AGREEMENT ON TIMING...SO STAYED CLOSE TO THE MULTI-MODEL CONSENSUS. MEAN TROF AXIS LOOKS TO RETROGRADE SLIGHTLY FOR EARLY NEXT WEEK...PLACING NRN NEW ENGLAND IN THE ACTIVE SW FLOW PORTION OF THE TROF EXIT REGION. THIS ORIENTATION WOULD LEAD TO MORE FREQUENT CHANCES FOR PCPN THAN WE/VE SEEN THE LAST SEVERAL OF WEEKS.
-- End Changed Discussion --
&& .AVIATION /07Z TUESDAY THROUGH SATURDAY/...
-- Changed Discussion --
SHORT TERM /THROUGH WEDNESDAY/...IFR CONDITIONS THIS MORNING WILL IMPROVE SOMEWHAT TODAY BUT MVFR CONDITIONS SHOULD PERSIST MOST LOCATIONS. CONDITIONS LOOK TO COME BACK DOWN TO IFR TONIGHT AND FOR A GOOD PORTION OF WEDNESDAY AS MOIST NORTHEAST FLOW CONTINUES. LONG TERM...CONDITIONS WILL GRADUALLY IMPROVE INTO THU AS HIGH PRES BUILDS INTO THE REGION. A SMALL WINDOW OF VFR SHOULD GIVE WAY TO INCREASING CLOUDS AGAIN LATE FRI AS DEEP...MOIST SLY FLOW DEVELOPS. A COLD FNT WILL SWEEP ACROSS THE AREA SAT...WITH A PERIOD OF IFR OR LOWER CONDITIONS POSSIBLE.
-- End Changed Discussion --
&& .MARINE...
-- Changed Discussion --
SHORT TERM /THROUGH WEDNESDAY/...SCA FOR THE OCEAN WATERS IS EXPECTED TO END MIDDAY TODAY...PERHAPS A FEW HOURS SOONER AS THE STIFF NORTHEASTERLY FETCH SUBSIDES. THERE IS A LOW PROB OF THE REEMERGENCE OF LOW-END SCA CONDITIONS LATE WED AS THE GRADIENT TIGHTENS AGAIN. LONG TERM...A PERIOD OF SLY FLOW LOOKS TO BUILD SEAS TO AROUND 5 FT LATE IN THE WEEK BEFORE A COLD FNT CROSSES THE WATERS. BEHIND THE FNT GUSTY WLY WINDS MAY KEEP SEAS NEAR 5 FT.
-- End Changed Discussion --
&& .GYX WATCHES/WARNINGS/ADVISORIES...
-- Changed Discussion --
ME...NONE. NH...NONE. MARINE...SMALL CRAFT ADVISORY UNTIL NOON EDT TODAY FOR ANZ150-152-154.
-- End Changed Discussion --
&& $$ NEAR TERM...EKSTER SHORT TERM...EKSTER LONG TERM...LEGRO

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