Big Squaw Snow Report

728 FXUS61 KGYX 150621 AFDGYX Area Forecast Discussion National Weather Service Gray ME 221 AM EDT Sat Aug 15 2026 .WHAT HAS CHANGED... No significant changes since the previous forecast cycle. && .KEY MESSAGES... 1. High pressure will bring dry weather to start the weekend with seasonably cool nights. 2. Rain accompanies a passing system Sunday night into Monday morning. A period of heavy rainfall will be possible which may result in nuisance flooding or ponding in poor drainage areas for the morning commute. && .DISCUSSION... KEY MESSAGE 1 DESCRIPTION... Canadian high pressure will continue to provide tranquil weather conditions today. Mainly sunny skies this morning will becoming partly cloudy this afternoon as some weak daytime instability develops, resulting in a fair weather cu field. High temperatures will be near seasonable averages, with readings ranging from the lower 70s across the north to the upper 70s and lower 80s south. Mainly clear skies are expected tonight, which combined with light winds and relatively low dew points will allow for radiational cooling. Forecast lows range from the lower to middle 40s across some interior valleys with upper 40s and lower 50s elsewhere. Valley fog is likely to develop overnight and persist into early Sunday morning. Sunday begins with high pressure overhead, quickly exiting east into the open Atlantic. Surface return flow combined with a WSW low level flow will begin to saturate the low levels while high clouds overrun from the west. Right now, mid level saturation isn`t likely until the late afternoon or evening, and this keeps rain chances lower through the day until the evening and overnight hours. KEY MESSAGE 2 DESCRIPTION... Forecast ensemble IVT plumes differ in magnitude and trajectory, with a more northeastward segment from the ECMWF ENS than the GEFS (a northward suppression, more progressive through the Mid Atlantic). In line with this vapor transport in the ENS, EFI QPF fields have also jumped comparing guidance from Wednesday evening to Thursday evening`s runs indicating some potential for an above average precipitation event. Shift of tails however remains muted, with an extreme precipitation event unlikely. Warm cloud depth in deterministic models is impressive, with runs of the GFS, ECMWF, NAM, and Canadian all depicting depths greater than 12kft for a period late Sunday night and early Monday morning. Coinciding with above normal PWATs around 2 inches, a period of heavy rain is becoming more likely, but exact location and radar presentation will need to be resolved with time. One of the larger differences in guidance, and therefore an important distinction between outcomes, is how far south the trough or low cuts into southern New England. A track further into southern New England could kink vapor transport, limiting moisture depth and duration, while a flatter path across northern New England keeps this SW moisture flux open, resulting in more efficient rain processes. Remaining rain tapers off through the day Monday, with drier weather and a bit of a warmup through midweek as highs climb into the lower to mid 80s. The next chance for rain then looks to be Wednesday into Thursday as an elongated cold front approaches from Quebec. It is yet to be determined if a wave develops out of this front, but could offer some rain enhancement depending on location through northern New England. && .AVIATION /06Z SATURDAY THROUGH WEDNESDAY/... Through 06Z Sunday: VFR conditions through Saturday night, except at LEB and HIE where valley FG is likely both this morning and tonight... mainly between roughly 06Z-12Z each day. This will bring IFR-LIFR restrictions. Light and variable winds early this morning become NW later today at 5-15 kts before becoming light and variable again tonight. No enhanced LLWS is anticipated through the period. Outlook: Sunday: VFR expected through the afternoon. Sunday night: MVFR/IFR cigs in RA, RA may be heavy at times limiting vis. Monday: Decreasing RA coverage, improvement towards VFR likely for points outside of the mountains. Monday night and Tuesday: VFR. No sig wx. Wednesday - Wednesday night: VFR. SHRA possible late ahead of an incoming cold front. && .MARINE... High pressure will continue to result in winds and seas remaining below SCA criteria through at least tonight. Southerly winds increase Sunday, with gusts 25 to 30 kt overnight into Monday morning. A low will cross northern New England and then the coastal waters Monday. It is possible a low level inversion keeps these gusts below SCA criteria. High pressure passes through the Mid Atlantic into midweek, before another cold front approaches from the west. && .GYX WATCHES/WARNINGS/ADVISORIES... ME...None. NH...None. MARINE...None. && $$ DISCUSSION...Tubbs/Clair/Cornwell AVIATION...Tubbs