062 FXUS61 KGYX 061707 AAC AFDGYX Area Forecast Discussion...UPDATED National Weather Service Gray ME 107 PM EDT Wed Oct 6 2021 .SYNOPSIS... High pressure moves into the area today and lasts for much of the coming week. Therefore, plenty of sunshine expected this week. Temperatures will be above normal until a cold front comes in on Friday bringing cooler weather for the weekend. && .NEAR TERM /THROUGH TONIGHT/... 1135 AM Update: Have made additional adjustments for the stubborn region of clouds that is slowly eroding...but has kept temperatures from moving upward for portions of southern ME and central NH. Do expect temperatures to quickly rebound as skies clear...but overall this may keep highs 1-2F lower in these areas vs originally forecast. No other significant changes to the forecast at this time. 920 AM Update: Primary change this hour is to boost sky cover in area of 5-6kft cloud deck that has been stubborn to budge over much of NH and southern/western ME. A gradual improving trend is expected...but cloudy/mostly cloudy skies will likely dominate in parts of central NH into early afternoon. No other significant changes to the forecast at this time. 730AM UPDATE... Made some adjustment to sky cover forecast based on latest satellite trends. The cloud deck in the western part of the area has snuck across the mountains as it was high enough to not be fully blocked by them. It's showing signs of being eroded from both ends at this point so may not last that much longer. However, we did increase cloud cover forecast through the morning as a result. ORIGINAL DISCUSSION... High pressure at the surface will control the weather today, and for the next several days as well. This is beneath the subsident region of the upper level ridge whose axis generally exists over the eastern Great Lakes. Currently there remains some moisture trapped beneath this subsidence generally at about 850 MB which is showing up in a rather extensive cloud layer at about 5000 FT. Eventually drier air will erode this cloud layer today and the northern edge of this cloud already shows this slow erosion from the north. We may keep the clouds through a good part of the morning especially in western areas, but eventually we expect the sun to break through. We should see high temperatures in the upper 60s to low 70s today with very little wind. && .SHORT TERM /THURSDAY/... A clear and calm night is expected as high pressure remains over the area. This will set up ideal cooling conditions with temperatures collapsing toward the dewpoint. Fog is likely in valley locations, with the favored valleys likely to see some dense fog by morning. Lows will primarily be in the 40s, buoyed by the low level moisture. Thursday will see plenty of sunshine, light winds, and highs in the low 70s. && .LONG TERM /THURSDAY NIGHT THROUGH TUESDAY/... Operational and ensemble guidance remain in relatively good agreement as we continue dry conditions to start out the extended portion of the forecast. On Friday, a backdoor cold front will sweep across the region from the Canadian Maritimes. Despite this front, there will still be a fair amount of sunshine as this system will be relatively moisture starved. H8 temperatures will begin the day near +10C over western portions of the forecast area. This will yield afternoon temperatures in the upper 60s over northern and eastern areas with lower 70s elsewhere as above normal temperatures for this time of the year continue. An area of Canadian high pressure will build into northern New England on Saturday with an easterly flow continuing over the region. Moisture will begin to wrap around the high from the Gulf of Maine. Therefore, expect temperatures will be about 10 degrees cooler than Friday, mainly in the upper 50s to lower 60s. Clouds will continue to fill in across the forecast area on Sunday, especially over western sections where there will be a slight chance for a shower. It will gradually become more humid with high temperatures in the lower 60s. A weak system will pass south of New England on Monday. This will allow for scattered showers in all areas to start off the week. && .AVIATION /18Z WEDNESDAY THROUGH SUNDAY/... Short Term... Summary: High pressure remains centered over the region through the short term period with the only impactful weather for aviation taking the form of overnight valley fog. Restrictions: VFR conditions will dominate through Thursday night outside of overnight fog in the 07-14Z window. Overall VLIFR/LIFR fog potential for both tonight and again Thursday night will be best at HIE/BML per climatology...but a briefer period of fog also looks likely at CON/AUG. Winds: Outside of afternoon seabreezes along the coast pushing onshore winds to 5-10kts...winds will remain largely calm- light/variable through the short term period with high pressure overhead. Lightning: No lightning is expected through Thursday night. Low Level Wind Shear / LLWS: No LLWS is expected through Thursday Night. Long Term...High pressure over the area brings light winds and mostly clear conditions for several days. Morning fog is almost certain each morning at LEB and HIE and possible at other TAF sites as well. A cold front drops south on Friday and Friday night, bringing in a cooler and drier air mass. However, a period of MVFR conditions will be possible immediately in the wake of the cold front Friday night into early Saturday. && .MARINE... Short Term...Very light winds expected as high pressure remains over the region. Long Term...High pressure brings quiet conditions for several days. A cold front drops south across the waters during the day on Friday and may lead to SCA conditions Friday night into Saturday when the pressure gradient is tightest and cold air advection is ongoing. && .GYX WATCHES/WARNINGS/ADVISORIES... ME...None. NH...None. MARINE...None. && $$ SYNOPSIS... NEAR TERM...Arnott SHORT TERM... LONG TERM... AVIATION...Arnott MARINE...