708 FXUS61 KGYX 221128 AFDGYX Area Forecast Discussion National Weather Service Gray ME 628 AM EST Fri Dec 22 2023 .SYNOPSIS... High pressure will bring dry conditions with chilly nights and seasonable daytime highs through Saturday. A weak system will bring clouds and the chance for some sprinkles and flurries by Saturday night and Sunday with significant impacts not expected. Mild and dry conditions are expected on Christmas Day and Tuesday before the weather turns unsettled again by midweek. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... 625 AM Update...Very little change to the going forecast at this time as it remains on track and close to latest obs. Previously... SFC high pressure crests over our region today allowing for calming winds and cool temperatures along with plenty of sunshine. && .SHORT TERM /6 PM THIS EVENING THROUGH 6 PM SATURDAY/... High pressure gradually moves off to the east tonight with WAA getting going aloft. The night should start out mostly clear and calm which will allow temperatures to drop rather quickly. However, the WAA regime will likely aid in increasing high clouds overnight. The cloud thickness will determine whether or not temperatures continue to quickly fall. Did not go with a rock bottom forecast at this time based on the uncertainty in cloud cover after midnight. Saturday should be another dry day with varying amounts of clouds. With winds turning south, temperatures will warm above today's values by about 5 degrees. && .LONG TERM /SATURDAY NIGHT THROUGH THURSDAY/... Overview: High pressure anchored offshore will dominate to start this forecast period. All eyes will be on the second half as ensembles signal the potential for another strong low pressure to develop and move into the region bringing our next chance for widespread precipitation. Details: A shortwave trough crosses the area Saturday night bringing little in the way of weather impacts as it runs into the aforementioned high pressure offshore and dives south. There is some areas of forcing focused over southern New Hampshire but with PWATs mostly around 0.5", I wouldn't expect more than a brief snow, or wintry mix, shower with little chance of any accumulation. Lows look to be in the 20s for a majority of the area with low 30s possible in the coastal plain. Cloud cover will increase Sunday as southerly flow will help to usher in a moister airmass, but also a slightly warmer one as 925 millibar temperatures climb just above freezing. This likely translates to highs in the upper 30s to mid 40s. Onshore flow and clouds will help to lock in nighttime lows at or just above freezing south of the mountains, and upper 20s to the north. Ridging looks to take back full control on Monday and although some clouds stick around, continued southerly flow will make for a mild Christmas Day. Temperatures at 925 millibars now look to be more like 3C and 4C which suggests high temperatures in the 40s across the board as well as a warmer night with lows right around the freezing mark. Tuesday sees high temperatures a degree or two warmer with areas of southern New Hampshire and Maine standing a chance to get near 50F. The same applies for lows Tuesday night with widespread temperatures above freezing looking likely south of the mountains. This is where our weather is likely to turn active as high pressure exits the region and low pressure moves in. Impacts are going to rely heavily on the exact track and timing of the low, something guidance struggles with at this time range. With warm air locked in this is looking like a mostly rain event. The GFS, Euro, and Canadian all target the Wednesday-Thursday time frame with large differences in strength and position of the low center. The 00Z GFS has come in line with the earlier Euro, taking a more inland track which may mean some snow for the mountains as cold air wraps in behind the departing low, but these details need more time to become clearer. Models also depict another strong Atlantic moisture feed spanning the East Coast. This shows in their respective ensembles, as they show PWATs around 0.75" and probabilities of QPF greater than 0.5" in the 50-60% range for most of the area. Due to all the uncertainty, I stuck with the NBM, but this will be something to keep a close eye on in the coming days. && .AVIATION /12Z FRIDAY THROUGH TUESDAY/... Short Term...VFR prevails at all sites through Saturday. Winds will be less than 10 knots, but possibly increase a bit with gusts around 15 knots Friday afternoon. Long Term...VFR will prevail through most of Tuesday with the only exception being on Saturday night into Sunday, where MVFR ceilings and light showers are possible at LEB and HIE. && .MARINE... Short Term...SCAs for the outer waters will come to an end by mid afternoon, with Penobscot Bay ending this morning. High pressure moves in today and moves offshore later tonight and Friday resulting in increasing southerly flow. Long Term...High pressure settled over the waters will keep wind and waves below SCA conditions through Tuesday. Winds will be generally west-southwesterly, with a brief northerly turn Sunday night and Monday. && .HYDROLOGY... The Kennebec River at Skowhegan will remain in minor flood into about midday today before the river continues to gradually recede. && .GYX WATCHES/WARNINGS/ADVISORIES... ME...None. NH...None. MARINE...Small Craft Advisory until 4 PM EST this afternoon for ANZ150- 152-154. Small Craft Advisory until 9 AM EST this morning for ANZ151. && $$ NEAR TERM...Ekster SHORT TERM...Ekster LONG TERM...Baron