Area Forecast Discussion
Issued by NWS Portland, ME

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321 FXUS61 KGYX 180713 AFDGYX Area Forecast Discussion National Weather Service Gray ME 313 AM EDT Wed Apr 18 2018 .SYNOPSIS... Low pressure will linger across the Maritimes today and this will bring more cloudy weather with rain and snow showers - mostly in the mountains. Low pressure passes to our south on Thursday bringing some light rain and snow, especially across southern NH and southernmost ME. Things are looking up however as high pressure finally builds into New England over the weekend into early next week. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... Upper level low pressure will linger across New England today. This will mean plenty of clouds for the region, but shower activity should be mainly confined to the mountains. Temperatures will be on the up and up today with highs around 50 quite likely on the coastal plain. Winds will be gusty at times as well - with gusts around 25 MPH a likelihood during the early afternoon hours. && .SHORT TERM /6 PM THIS EVENING THROUGH 6 PM THURSDAY/... Fast moving low pressure over the Ohio Valley today will quickly move eastward to near Nantucket midday Thursday as a phase of two short wave troughs takes place to our west. The result will be light precipitation overspreading southern zones late tonight, which will then overspread much of the rest of the forecast area during the morning hours on Thursday. Boundary layer temperatures will be the key to the precipitation types during this time. It does appear that the precipitation will arrive prior to dawn across southern NH and this will aid in a better chance of accumulating snowfall there - especially in the Monadnocks where a couple of inches on cold surfaces will be possible. Lower elevations such as the Merrimack Valley will likely see snowflakes but accumulations will likely be pretty hard to come by. Further north into Maine and other lower elevation locations across New Hampshire, mainly rain is expected during the day Thursday - but heavier bursts of precipitation could bring a brief change to or a mix with snow, especially prior to the late morning hours. && .LONG TERM /THURSDAY NIGHT THROUGH TUESDAY/... The deterministic model solutions are in decent agreement on the long wave pattern through late next week. We begin the period with an upper low across the northeast CONUS. This upper low will translate east and into the maritimes where it will maintain the cool cyclonic flow across the area for much of the upcoming weekend. At the surface...low pressure will exit into the maritimes Thursday night with precipitation tapering to some lingering wrap around rain and snow showers. Plenty of clouds Friday in the cool cyclonic flow with upslope showers confined mainly to the higher terrain. Clouds linger Saturday across the higher terrain as well as our northern and eastern Maine zones with any showers confined to the higher terrain. By sunday ridging and rising heights will then greet the area in time for the first half of the new week along with a noticeable warming trend. Northern stream energy should drive a cold front across the area on Thursday. The jury remains out on timing and to what degree phasing will occur between northern and southern stream energy and how strong and progressive the frontal system and an ocean low will be. && .AVIATION /07Z WEDNESDAY THROUGH SUNDAY/... Short Term...VFR conditions are expected today outside of the mountains. MVFR conditions are expected in the mountain areas. MVFR conditions return across southern NH late tonight in light rain and/or snow which then overspreads the rest of the region Thursday morning. Long Term... Thu night...MVFR with areas of IFR in shra/shsn and fog. Fri - Sat...Areas of MVFR in cigs with sct mtn -shra/-shsn. && .MARINE... Short Term...SCA in effect outside the bays today for wind gusts around 25 kt and seas at or greater than 5 ft. These conditions subside this evening. Long Term... Fri - Sat...SCA`s are psb...especially outside the bays. && .HYDROLOGY... Suncook River at North Chichester should fall to below flood stage by 10 am today. Otherwise area rivers will remain below flood stage for the next several days. && .TIDES/COASTAL FLOODING... Tide anomalies are still running around 1 ft above. However, seas are subsiding as are winds. This should allow for little to no tidal problems today and tonight. && .GYX WATCHES/WARNINGS/ADVISORIES... ME...None. NH...None. MARINE...Small Craft Advisory until 8 PM EDT this evening for ANZ150- 152-154. && $$ NEAR TERM...Ekster SHORT TERM...Ekster LONG TERM...Schwibs

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