Casco Bay Marine Forecast
| Tonight...Nw Winds 5 To 10 Kt, Diminishing To Around 5 Kt Late This Evening And Early Morning, Then Becoming Sw Towards Daybreak. Seas Around 2 Ft This Evening, Then 1 Foot Or Less. |
| Mon...Sw Winds 10 To 15 Kt With Gusts Up To 20 Kt, Becoming S 15 To 20 Kt With Gusts Up To 30 Kt In The Afternoon. Seas 2 To 4 Ft. A Chance Of Rain In The Afternoon. |
| Mon Night...Sw Winds 20 To 25 Kt, Becoming W 15 To 20 Kt After Midnight. Gusts Up To 35 Kt. Seas 2 To 4 Ft. Rain, Mainly In The Evening. |
| Tue...W Winds 15 To 20 Kt With Gusts Up To 30 Kt. Seas 2 To 3 Ft. |
| Tue Night...W Winds 15 To 20 Kt With Gusts Up To 30 Kt, Diminishing To 10 To 15 Kt With Gusts Up To 20 Kt After Midnight. Seas 2 To 3 Ft. |
| Wed...W Winds 10 To 15 Kt With Gusts Up To 20 Kt. Seas Around 2 Ft. A Chance Of Rain In The Afternoon. |
| Wed Night...Sw Winds 10 To 15 Kt With Gusts Up To 20 Kt, Becoming W 15 To 20 Kt With Gusts Up To 30 Kt After Midnight. Seas Around 2 Ft. Rain Likely. |
| Thu...Nw Winds 20 To 25 Kt With Gusts Up To 35 Kt. Seas 2 To 3 Ft. A Chance Of Rain In The Morning. |
| Thu Night...Nw Winds 15 To 20 Kt, Becoming W 5 To 10 Kt After Midnight. Seas 2 To 3 Ft. |
| Fri...Sw Winds 10 To 15 Kt, Increasing To 15 To 20 Kt In The Afternoon. Seas 2 To 3 Ft. |
| Fri Night...Sw Winds 15 To 20 Kt With Gusts Up To 30 Kt. Seas 2 To 4 Ft. A Chance Of Rain In The Evening, Then Rain Likely After Midnight. |
| Area Forecast Discussion National Weather Service Gray ME 1259pm EST Sunday Nov 2 2025 Synopsis High pressure moves east of New England through the overnight. A series of shortwave troughs move through this week, bringing generally cool, windy, and at times unsettled conditions. Near Term - Through Tonight High pressure moves east of the Gulf of Maine through the overnight hours tonight. Clear skies and light winds prevail, allowing for radiational cooling conditions overnight. Low to mid 20s are expected across the interior, with upper 20s to near 30 expected along the coastline. For many spots along the immediate coastline, tonight will be the first freeze of the season. Short Term - Monday Through Monday Night Tomorrow features a modest warm up on southwesterly flow ahead of an approaching cold front. The day starts off sunny, but clouds gradually increase from the south and west through the day. Highs warm into the low 60s across southern towns, with mid to upper 50s expected elsewhere. There is a chance for a round of showers to move through southern New Hampshire and along the Maine coast during the afternoon hours. There's still some uncertainty as to whether these will mostly stay offshore, or move through during the afternoon hours. We'll continue to watch the trends with these. A more organized area of showers and some embedded heavier downpours associated with the front arrives into western areas around sunset. The front moves through during the evening hours tomorrow night, with showers likely across the whole forecast area. Generally less than 1/4in of rainfall is expected, but some amounts up to a half inch are possible across the higher terrain and near the Canadian border. The front moves offshore shortly after midnight. Colder air begins moving back in behind the front overnight. Upslope rain and snow showers develop across the higher terrain through the overnight, with enough moisture to bring accumulating snowfall to the higher peaks above 3000ft. Long Term - Tuesday Through Sunday Key Messages: * An active but low impact pattern continues through the long term with various chances of precipitation. * Gusty winds are likely on Tuesday and Thursday with gales possible over the coastal waters. Forecast Details: We should still see some ongoing shower activity through the day on Tuesday behind the departing upper trough/surface front, especially in the mountains given the upslope flow (snow accumulations will be possible over the higher peaks). Our region will be nestled in between low pressure over the northern Atlantic, and high pressure located across the southeast CONUS. Thus, we will have a decent pressure gradient with some modest pressure rises behind the front. Cold air advection should also be fairly strong. GFS (Global Forecast System) soundings suggest around 40 knots at the top of the mixed layer Tuesday into Tuesday night so we will see some gusty westerly winds during this time period. Additionally, gales will remain possible over the coastal waters through the day on Tuesday. Temperatures will be a bit cooler behind the front with highs on Tuesday mainly in the 40s north, to the low to mid 50s south. Some highs in the 30s will be possible over the mountains. Winds and precipitation chances should gradually diminish Tuesday evening/night as low amplitude ridging approaches. Wednesday should mainly be dry during the day as the ridge axis quickly moves across the region. Highs will be similar to Tuesday, but maybe just a touch warmer in the mountains. A compact shortwave/front then approaches Wednesday evening/night which will lead to our next widespread precipitation chances through early Thursday. Given the progressive nature of the relatively weak wave, amounts should generally be light. The latest NBM run suggests low to medium chances of liquid totals greater than or equal to a quarter of an inch and generally low chances for any totals greater than a half inch outside of the mountains. Some showery activity may linger across the mountains through the day on Thursday behind the front and we are likely to see another windy day and more potential gales over the coastal waters. Highs will be cooler, mainly in the lower 40s to the lower 50s but we will likely see widespread 30s over the higher terrain. More progressive ridging moves across the region on Friday, giving us another break from precipitation and slightly warmer temperatures. Then, like a broken record, the next wave approaches Friday night into Saturday with our next widespread precipitation chances. While there's still quite a bit of uncertainty regarding this late week/weekend system, precipitation amounts are still expected to be relatively light at this time. Thus continues our low impact active pattern. Some guidance suggests a decent warmup through the weekend but NBM spread increases markedly starting on Friday, likely due to the low predictability nature of these progressive features and their timing. As a final note, astronomical high tides peak mid to late week so some minor coastal flooding is not out of the question, especially with the frontal passage Wednesday night into Thursday. Marine Short Term High pressure moves east of the waters through the overnight. An approaching cold front brings SCA (Small Craft Advisory) conditions in southwesterly flow ahead of the front tomorrow afternoon and evening. The front crosses the waters shortly after midnight Monday night, with westerly gales possible behind the front. Long Term Gusty westerly winds will be ongoing on Tuesday with gales possible over the coastal waters. Seas and winds should relax a bit on Wednesday but another round of SCA (Small Craft Advisory) conditions and/or gales is possible late Wednesday night through Thursday night. NOAA Gray/Portland ME Office - Watches - Warnings - Advisories ME...None. NH...None. Marine Small Craft Advisory from 1pm Monday to 1am EST Tuesday for ANZ150>154. Gale Watch from late Monday night through Tuesday evening for ANZ150>154. |
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