| NWS Forecast for: 18NM NNE Portsmouth NH Atlantic Ocean Issued by: National Weather Service Gray/Portland, ME Last Update: 5:12 am EDT Sep 14, 2026 | |
| This Afternoon: NW wind around 25 km/h, with gusts as high as 40 km/h. Sunny. Seas 1 m or less. Tonight: NNW wind 5 to 10 km/h. Clear. Seas 1 m or less. Tuesday: N wind 5 to 10 km/h becoming SE in the afternoon. Sunny. Seas 1 m or less. Tuesday Night: S wind 5 to 10 km/h becoming SSW after midnight. Partly cloudy. Seas 1 m or less. Wednesday: SW wind around 10 km/h. Mostly sunny. Seas 1 m or less. Wednesday Night: Variable winds 5 km/h or less. Partly cloudy. Seas 1 m or less. Thursday: NNE wind 5 to 10 km/h becoming ESE in the afternoon. Partly sunny. Seas 1 m or less. Thursday Night: SSE wind 5 to 10 km/h becoming W after midnight. Showers likely. Seas 1 m or less. Friday: NNW wind around 10 km/h becoming NE in the afternoon. Mostly sunny. Seas 1 m or less. | |
| Marine Point Forecast: 43.31°N 70.57°W Associated Zone Forecast which includes this point | |
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