Area Forecast Discussion
Issued by NWS Portland, ME

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610 FXUS61 KGYX 181542 AFDGYX Area Forecast Discussion National Weather Service Gray ME 1142 AM EDT Mon Sep 18 2017 .SYNOPSIS... High pressure will hold over the region today through tonight as Jose approaches from the south. Jose will meander southeast of Long Island Tuesday through Friday and will gradually die out over the weekend as high pressure remains in control over the northeast. && .NEAR TERM /UNTIL 6 PM THIS EVENING/...
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1144 AM Update... Have updated forecast based on latest conditions. Dense fog continues to slowly lift across the forecast area, however it will take a few more hours to lift near the shoreline. Have adjusted the coastal waters to hold onto the fog throughout the day. Made adjustments to cloud forecast, temperatures and dew points for this afternoon. 700 AM Update... Fog and ocean stratus hanging tough across southern Maine and New Hampshire this morning. A dense fog advisory remains in effect until 900 AM. Expect fog to lift over the next couple of hours but may take until early afternoon to poke holes in the overcast mainly in southern interior sections. Stratus may be around for much of the day in coastal locations as moist onshore flow continues. Have adjusted temp/td/rh grids based on current obs. No other changes planned attm. Prev Disc... High pressure will remain nosed in from the east over the region today with a moist onshore flow continuing. Ocean stratus has overspread much of south and central Maine as well as southeast New Hampshire early this morning. Dense fog has once again formed in the coastal plain and portions of southern interior Maine and New Hampshire. Expect fog to gradually lift through the morning hours. Ocean stratus will gradually erode from north to south through the early afternoon hours but may hang tough in the coastal plain for much of the day. High temperatures will reflect this pattern with coastal and southern interior sections only getting into the mid 60s to near 70. Warmest readings will be found in the mountains and connecticut Valley where highs will top out in the mid to upper 70s.
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&& .SHORT TERM /6 PM THIS EVENING THROUGH 6 PM TUESDAY/... Ocean stratus will flood northward again this evening and fog will once again develop in coastal and southern interior sections overnight. As Jose approaches from the south will see a chance of showers pushing in from the south after midnight with highest pops by Tuesday morning in southern and coastal areas. Lows will range from the lower to mid 50s in the north to the mid 50s to near 60 south. Tuesday looking mostly cloudy with occasional rain in the the south and mostly cloudy skies with scattered showers in the north. Most areas downwind of the mountains will only see highs in the mid to upper 60s. Warmest temps will once again be seen in far northwest zones with highs reaching the lower to mid 70s. && .LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/... The main area of concern in the long term forecast is the track of Jose and how far north its effects will be expected in Northern New England. At the moment, there are tropical storm watches up to the south in Boston`s forecast area. The baseline of the long term forecast is started with SuperBlend and then adjusted towards GFS/SREF in the first 48 hours to match neighboring office that have more of an effect from Jose. Overall confidence is average...but there is still uncertainty when it comes to tropical system forecasts. Based on current model guidance and NHC...Jose is still expected to track south of our area. This will allow for some much needed rain along coastal regions with the highest amounts in Southeast NH and over the islands and marine zones. At the moment...we could see around 2 inches in Southeast NH over 2 day period. Due to the slower track as noted before, rainfall may not begin to the afternoon or evening of Tuesday. We do expect hazardous seas and winds in the Gulf of Maine and will not rule out isolated tropical storm wind gusts along the coast in Southeast NH. Due to the winds, waves, and tides expected during Jose`s presence in Southern New England waters, the potential for beach erosion and minor coastal flooding are possible. This is further discussed below in the Tides/Coastal Flooding Section. On Tuesday evening...Jose is expected to still be classified as a Hurricane in the Atlantic well offshore of New Jersey area. Being a tropical system, effects can be felt at great distances. By Wednesday should be southeast of Cape Cod and be classified as a tropical storm. The ridge of high pressure over our area will help keep the track south of our region and have it spin out to the southeast before going southwest on Friday morning. The current models and NHC projections will allow seas to start to build on Tuesday and rain to overspread the coastal areas and decreasing rapidly north of Portland. Rain will diminish on Wednesday afternoon to early evening. Upper level ridge will dominate our region from Thursday through the weekend. Climate outlook and teleconnections continue to suggest above normal temperatures through the rest of September and potential of above normal precipitation. Based on over all pattern...most of the precipitation will come from the active tropical systems in the southern Atlantic. && .AVIATION /16Z MONDAY THROUGH FRIDAY/... Short Term...IFR/LIFR ceilings and vsby in southern and coastal zones this way to MVFR/IFR conditions this afternoon. IFR/LIFR ceilings and vsby redeveloping tonight and persisting into Tuesday. Long Term...IFR/LIFR ceilings overspread much of coastal and southern interior zones Tuesday night and will persist into Wednesday early afternoon. Conditions will begin to improve around late Wedensday. VFR conditions expected Thursday and Friday. && .MARINE... Short Term...Onshore flow will gradually increase tonight through Tuesday as Jose approaches from the south. Sca`s will likely be needed by Tuesday Evening. Expect seas to build to 4 to 7 feet by the end of the day Tuesday. Long Term...Areas of dense fog through tonight. Long period swells will approach the coast beginning late Tuesday as Jose moves northeast of Long Island. Northeast winds will increase Tuesday night into Wednesday as well, when tropical storm conditions are possible. && .TIDES/COASTAL FLOODING... Hurricane Jose is forecast to cross the southern New England waters on Wednesday. This will result in long period swell. Matrices suggest there will be increased risk for beach erosion and splash-over during this period. For now, the storm surge guidance (ESTOFS) is only indicating about a half foot to one foot of storm surge. Highest storm surge is right near the MA border. Tides are around 10.5 or higher and with the combination of Jose, there is potential for minor coastal flooding. Dangerous rip currents are also possible and high surf advisories may be needed during Tuesday evening through Wednesday. && .GYX WATCHES/WARNINGS/ADVISORIES... ME...None. NH...None. MARINE...None. && $$ JC is the U.S. government's official web portal to all federal, state and local government web resources and services.