Casco Bay Marine Forecast
| This Afternoon...Nw Winds Around 10 Kt. Seas Around 2 Ft. A Slight Chance Of Showers Early, Then A Chance Of Showers Late. |
| Tonight...Nw Winds 10 To 15 Kt With Gusts Up To 20 Kt. Seas Around 2 Ft. |
| Fri...Nw Winds 10 To 15 Kt With Gusts Up To 20 Kt. Seas Around 2 Ft. |
| Fri Night...Nw Winds 10 To 15 Kt With Gusts Up To 20 Kt. Seas Around 2 Ft. |
| Sat...W Winds 10 To 15 Kt With Gusts Up To 20 Kt. Seas Around 2 Ft In The Morning, Then 1 Foot Or Less. |
| Sat Night...Sw Winds 5 To 10 Kt. Seas 1 Foot Or Less, Then Around 2 Ft After Midnight. A Chance Of Rain In The Evening, Then Rain After Midnight. Vsby 1 Nm Or Less. |
| Sun...Sw Winds 10 To 15 Kt, Becoming W 15 To 20 Kt In The Afternoon. Seas 2 To 4 Ft. Rain. |
| Sun Night...W Winds 15 To 20 Kt With Gusts Up To 30 Kt. Seas 2 To 4 Ft. A Chance Of Rain. Vsby 1 Nm Or Less After Midnight. |
| Mon...W Winds 15 To 20 Kt With Gusts Up To 30 Kt. Seas 2 To 3 Ft. |
| Mon Night...W Winds 15 To 20 Kt With Gusts Up To 30 Kt. Seas 2 To 3 Ft. |
| Area Forecast Discussion National Weather Service Gray ME 132pm EST Thu Nov 13 2025 Synopsis Upslope snow showers are expected to continue this afternoon as northwest flow provides lift and instability. This upslope pattern should continue again tomorrow, with drier conditions expected Saturday. Low pressure moves in from Canada on Sunday, with wintry precipitation expected across interior NH and Maine. Behind the storm, breezy winds and upslope snow is possible Monday afternoon. High pressure moves in for the second half of next week. Near Term - Through Tonight The most recent radar loop currently shows light reflectivity returns across the interior, with observations showing portions of northern NH and interior Maine reporting light snow. Some locations south of the mountains have also reported light rain today as well. Mainly dry conditions are expected this afternoon, though more upslope precipitation is likely across the mountains and foothills through the rest of the day. Higher elevations may see a few inches of snow, though most valley areas should not expect more than a coating. As the sun sets, upslope should diminish. Light northwest flow will allow for overcast skies to remain north of the mountains, with skies gradually clearing through the night south of the mountains. Lows tonight look to be a little chillier than last night's with lows in the upper 20s most places. Short Term - Friday Through Saturday The upslope pattern experienced today will likely repeat itself during the day Friday, though upslope precipitation should be more isolated and fizzle out through the day. Highs on Friday and Saturday will be similar, and range from lower-30s in the north to mid-40s along the coast. By Friday night, high pressure works into the area and will allow for mostly clear skies through Saturday. Cloudier skies remain more likely north of the mountains with the light northwest flow expected. Clouds increase through the day Saturday as a low pressure system approaches northern New England. Long Term - Saturday Night Through Thursday Saturday night, a low moves in from the northwest. The low looks to interact with the cold surface air over the northeast, overrunning at least some of the colder air. This will allow for some snow and wintry mix north of the mountains and across western NH. However, models are much more uncertain how long the cold air dam over northern New England holds. Models have always struggled with this, and tend to have a warmer bias in these overrunning low situations. This time around, models are generally latching onto two distinct solutions. The first (GFS/CMC) bring more rain and wintry mix to the area, and completely overrun the cold air overhead. The second (ECMWF/NAM) bring the low further south, with secondary redevelopment over the Gulf of Maine. The development of the secondary low would disrupt the circulation advecting the warm air, allowing for rain across the coastal plain, but more consistent heavy, wet snow in the mountains. Both solutions agree that precipitation should be light. Liquid accumulations of about 0.5-1" are possible. A few inches of snow is possible across the interior, as well as a light glaze of ice in western New Hampshire. By Monday morning, the mentioned low will move offshore. A pressure gradient appears to form, potentially bringing breezy northwest winds early next week. Otherwise, next week looks cooler as a broad trough remains over the Northeast. Marine Short Term Coastal waters remain in NW cyclonic flow into Saturday as high pressure nears but passes to the south. Expect conditions to remain below SCA (Small Craft Advisory) for winds and waves, but could see a few gusts to 25 kt Friday evening...mainly on the outer waters. Long Term Next storm system approaches from the west Saturday evening, with a warm front lifting over the waters Sunday morning, then low/cold front that afternoon. Tight pressure gradient will bring strongest winds of the forecast period, W around 30 kts Sunday night through Monday evening. These will build waves 5 to 7 ft on the outer waters, but bays/harbors will be lower minus local wind wave. May need Gale headlines for the outer marine zones during this period. NOAA Gray/Portland ME Office - Watches - Warnings - Advisories ME...None. NH...None. Marine None. |
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