Area Forecast Discussion
Issued by NWS Portland, ME

Current Version |  Previous Version |  Graphics & Text |  Print | Product List |  Glossary On
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47
-- Highlight Changed Discussion --
-- Discussion containing changed information from previous version are highlighted. --
999 FXUS61 KGYX 271346 AFDGYX Area Forecast Discussion National Weather Service Gray ME 946 AM EDT Mon May 27 2024 .SYNOPSIS... A warm front will lift north today, passing through the region tonight. A cold front then passes overhead Tuesday. An upper level trough slowly crosses the region Wednesday through Friday with more scattered showers and near seasonable temperatures. High pressure passes south of the area this weekend. && .NEAR TERM /UNTIL 6 PM THIS EVENING/...
-- Changed Discussion --
Update... Drizzle, low clouds, stratus, showers and cold temperatures continue over much of the forecast area this morning which will continue into the afternoon hours. Some breaks in the clouds however can be expected over southern and western New Hampshire where temperatures will climb into the 65 to 70 degree range this afternoon. Prev Disc... 630am Update...Expanded and increased PoPs this morning as an area of showers traveling form southern NH to southern ME has blossomed. Did bump temps up a bit today. Considering how warm and mild last night was, the area should have a good start towards warming this afternoon. Minor adjustments made to the near term portion of the forecast for temperatures, surface dew points and winds. Previous Discussion... A mix of fog, drizzle, and showers this morning, before showers become more dominant this afternoon. Fog will be most impactful towards the coast and southern NH this morning, retreating back to the immediate coast for much of the afternoon. Overcast skies are expected today as onshore flow feeds the low levels with moisture amid an improving moisture depth. Daytime heating will contribute to some shower development this afternoon, but some uncertainty just how widespread or numerous these showers are. Not a washout, but also not as stellar as the previous two days with rounds of rain. Leaned a bit cooler with temperatures today considering the expected cloud cover, and that the warm front won`t arrive until this evening.
-- End Changed Discussion --
&& .SHORT TERM /6 PM THIS EVENING THROUGH 6 PM TUESDAY/... While these conditions will keep Monday moot on Memorial Day, the main area of precipitation arrives closer to the evening and overnight hours. Low pressure will push NE through the Great Lakes, lifting a warm front through the CWA. Hires guidance is depicting a plume of rain, perhaps with embedded thunder, to cross the region after 6pm local. The onshore flow component plus surging PWATs should allow for locally enhanced rainfall on the SE slopes of the Whites, where the heaviest rainfall totals are expected this event. While widespread impacts are not anticipated, hiking trails that cross flashy rivers or streams may become treacherous with runoff this evening and overnight. No big changes here in QPF, guidance has settled on an envelop that hasn`t changed too much. My modifications were mainly to decrease rainfall in the lee of the Whites where downsloping should limit QPF on the NW side. Temperatures may surge a few degrees warmer for a very mild night in May. Lows may only fall into the mid 60s for much of southern NH, with mid to upper 50s for southern ME. Tuesday is expected to be drier, but will feature a passing cold front that will freshen the area with drier air aloft and some deeper mixing with a breeze. Temperatures return to the mid 70s to low 80s for the day. There will be the chance of some showers with passage of the front, but some uncertainty on further instability that could cause some thunder. Opted to not include thunder at this time considering the dry air aloft which would likely limit coverage of deeper cells. && .LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/... Overview: An upper level trough and cutoff low pressure system will settle near Northern New England through much of next week, which will result in scattered showers at times along with near average temperatures. Drier conditions are then possible by next weekend. Impacts: Little to no major weather related impacts are expected. Forecast Details: Other than an isolated shower across the mtns and near Canadian Border, Tuesday night will be dry with lows into the 50s. A secondary cold front will then cross on Wednesday into Thursday as we remain under broad cyclonic flow with cutoff low pressure near the region. This will result in renewed chances for scattered showers at times along with partly sunny skies. Highs on Wednesday will be mild ahead of the front with readings into the 70s to near 80 degrees before cooler air arrives on Thursday with highs only into the 50s across the north and 60s to perhaps near 70 south. An isolated thunderstorm is possible on Wednesday as daytime heating allows for some modest instability to develop. Thursday night will be on the cool side with lows perhaps into the 30s across the north and 40s elsewhere. Slightly warmer temperatures are then possible on Friday as the h5 trough axis slowly begins to move east and much of the day should be dry. After another cool night on Friday, temperatures will slowly begin to recover towards next weekend with mainly dry conditions likely. && .AVIATION /14Z MONDAY THROUGH FRIDAY/... Short Term...Widespread IFR and LIFR expected today amid lowered ceilings and some visibility restrictions due to fog. SHRA becomes more widespread this afternoon, with more persistent RA this evening and overnight. LLWS possible in southern ME terminals this evening and overnight. Slow improvement to MVFR is expected Tuesday morning SW to NE. VFR will be possible for much of the area by mid Tuesday afternoon with winds gusting to around 20 kt with passing front. Long Term...Mainly VFR conditions are likely Tuesday night through Friday, although some MVFR restrictions will be possible at times within scattered -SHRA and lower ceilings. Some nighttime valley fog will also be possible, which could result in additional restrictions at KLEB and KHIE. && .MARINE... Short Term...SCA conditions expected today as onshore gusts increase. This will also promote a growing wind wave Tuesday, perhaps lingering into the evening. Periods of fog and low stratus expected today and tonight, which could cause low visibility. This improves Tuesday as a cold front passes over the waters. Long Term...Southerly winds become westerly behind a cold front Tuesday evening. Winds will then primarily remain out of the west through the remainder of the week with gusts at times approaching 20 kts. Seas of 4-6 ft across the outer waters are likely Tuesday through part of Wednesday before decreasing and remaining below 5 ft through the remainder of the week. Across the bays seas of generally 1-3 ft can be expected. && .GYX WATCHES/WARNINGS/ADVISORIES... ME...None. NH...None. MARINE...Small Craft Advisory until 4 PM EDT Tuesday for ANZ150-152-154. Small Craft Advisory from 6 PM this evening to 4 PM EDT Tuesday for ANZ151. && $$ Cannon/Tubbs