Area Forecast Discussion
Issued by NWS Portland, ME

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000 FXUS61 KGYX 150148 AAC AFDGYX Area Forecast Discussion...UPDATED National Weather Service Gray ME 948 PM EDT Mon Oct 14 2019 .SYNOPSIS... A cold front moves across the area tonight with a few showers possible in northern areas. High pressure builds in behind the front for Tuesday with pleasant weather expected. The next low pressure system begins affecting our area, with low pressure strengthening rapidly as it enters the Gulf of Maine Wednesday night. This will bring a period of heavy rain to northern New England, with gusty west winds behind the low on Thursday. High pressure builds in for the weekend. && .NEAR TERM /UNTIL 6 AM TUESDAY MORNING/... 945 PM Update... An area of showers are moving across the forecast area this evening as a weak cold front crosses. Most of the precipitation is across northeastern Maine and stretches to Farmington and Fryeburg. Some sprinkles are also possible across Cumberland County. This convection will wane and move east in the next couple of hours, setting up another foggy night. Adjusted winds, sky cover, and PoPs slightly for this update. 630 PM Update... Just a few minor changes to the forecast this evening as high pressure crosses the forecast area tonight. Readings will eventually drop into the mid to upper 30s north to lower to mid 40s south overnight. Previous discussion... A weak cold front will cross the region late this evening. Moisture is rather limited with this system however scattered showers will be possible, mainly over northern areas. There is very little gradient behind the front at the surface overnight. It is a challenging forecast in that some patchy fog may form once again over the interior if winds decouple with time. Some patchy fog may enter the Midcoast region once again as well. The coldest overnight lows will be over western sections where cold air advection will allow for H8 temperatures to fall below 0C. Lows will range from the mid 30s north and west to the mid 40s further to the south and east. && .SHORT TERM /6 AM TUESDAY MORNING THROUGH TUESDAY NIGHT/... A weak area of high pressure will crest overhead on Tuesday. This will allow for sunshine and relatively light winds throughout the day. Low pressure begins to move east from the Great Lakes region Tuesday night. Warm air advection ahead of the system may allow for an increase in cloudiness over western areas later at night. Daytime highs will be limited to the 50s in most areas. This sets the stage for rapid cyclogenesis along the Mid Atlantic coast for the extended portion of the forecast. && .LONG TERM /WEDNESDAY THROUGH MONDAY/... The ensemble and deterministic model solutions are in decent agreement on the long wave pattern through the upcoming weekend and the start of the new work week. We begin the period with weak ridging ahead of an upper low over the Great Lakes. At the surface...a ridge of high pressure will retreat well offshore during the day Wednesday as low pressure and a trailing cold front approach from the Great Lakes. An impulse pivoting around the upper low will result in secondary low development along the trailing front over the DELMARVA region by Wednesday afternoon. The deepening low center will ride northeast along the coast to near /KPSM/ Portsmouth by 12z Thursday. Strengthening onshore flow and a 70 kt low level jet in advance of this low should produce a band of heavy rain Wednesday night into Thursday morning. Steadier and heavier precipitation will taper from southwest to northeast during the afternoon following the passage of the surface low. Wrap around moisture and upslope flow will result in residual clouds and a few upslope rain/snow showers Thursday night and Friday across the higher terrain. A ridge of high pressure follows this departing storm system for Saturday. A weakening and moisture starved cold front will cross the area Sunday marked by a few clouds and perhaps a mountain sprinkle. The next disturbance approaches from the Great Lakes for late Monday into Tuesday. && .AVIATION /02Z TUESDAY THROUGH SATURDAY/... Short Term...Lower ceiling and patch fog will remain possible along the Midcoast region and across the inland valleys tonight with locally IFR or LIFR conditions. A few showers may cross northern areas. Drier Tuesday into Tuesday night as high pressure builds over the area. Long Term... Wed AM...Lcl IFR psb in AM valley stratus and fog. Wed night - Thu...IFR in RA and fog. Sfc winds gusting up to 30 kt. Fri...Sct MVFR psb in mtn -SHRA. NW surface winds gusting up to 25 kt. && .MARINE... Short Term...Winds shift to the west behind a front late tonight and Tuesday morning. Patchy fog is possible for much of the night. Winds and seas remain below SCA thresholds through Tuesday night. Long Term... Wed PM - Thu...Gales likely, with gusts approaching storm possible outside the bays. Fri...SCA`s likely. && .HYDROLOGY... Rain heavy at times Wednesday night into Thursday may result in urban and poor drainage flooding. At this time river flooding is not expected, but will have to watch our typically flashy rivers in the higher terrain where QPF could be higher. && .GYX WATCHES/WARNINGS/ADVISORIES... ME...None. NH...None. MARINE...None. && $$ NEAR TERM...Hanes SHORT TERM...Cannon LONG TERM...Schwibs is the U.S. government's official web portal to all federal, state and local government web resources and services.