Marine forecast
Boston Harbor, MA
- current wind
- 2 kt SSE
- Gusts
- 4 kt
- Seas
- 2.0 ft
- Period
- 3 sec
- Air
- 57°F
Observed Tue 3:00 PM | ANZ230
- Gusts now
- 4 kt
- Seas now
- 2.0 ft · 3 sec
- Air
- 57°F
- 72-hr peak
- 18 kt
- Peak seas
- 2 ft
In brief
At 3:00 pm EDT on Oct 13, 2026, NDBC station CSIM3 (Castle Island (NOS) 8444069, 5 miles away) measured wind from the SSE at 2 kt, gusting to 4 kt; buoy 44090 measured seas of 2.0 ft. The NWS forecast for Boston Harbor, MA issued at 1:04 pm EDT on Oct 13, 2026 reads, for this afternoon: “SE winds around 10 kt. Waves 2 to 3 ft.”
Source: National Weather Service Boston/Norton MA forecast; NDBC observations
Wind forecast · ktPeak 18 kt
Seas forecast · ftPeak 2 ft
NWS marine forecast
| Period | Forecast |
|---|---|
| This Afternoon | SE winds around 10 kt. Waves 2 to 3 ft. Patchy fog. A slight chance of showers. |
| Tonight | S winds 10 to 15 kt. Waves around 2 ft. A chance of showers. Patchy fog in the evening. |
| Wed | W winds 10 to 15 kt. Gusts up to 20 kt in the afternoon. Waves around 2 ft. |
| Wed Night | NW winds 10 to 15 kt. Gusts up to 20 kt after midnight. Waves around 2 ft. |
| Thu | NW winds 10 to 15 kt with gusts up to 20 kt, becoming N 5 to 10 kt in the afternoon. Waves around 2 ft in the morning, then 1 foot or less. |
| Thu Night | NE winds around 5 kt, becoming SE after midnight. Waves 1 foot or less. |
| Fri And Fri Night | S winds 10 to 15 kt, becoming W 20 to 25 kt. Gusts up to 30 kt. Waves 2 to 3 ft. Showers. |
| Sat And Sat Night | NW winds 25 to 30 kt, becoming W 20 to 25 kt. Waves around 2 ft. Seas are reported as significant wave height, which is the average of the highest third of the waves. Individual wave heights may be more than twice the significant wave height. |
Issued Tue 1:04 PM by Boston/Norton MA (product CWFBOX).
Recent buoy conditions
| Time | Wind | Gust | Seas | Water |
|---|---|---|---|---|
| Tue 3:00 PM | 2 kt SSE | 4 kt | — | — |
| Tue 2:54 PM | 3 kt SSE | 4 kt | — | — |
| Tue 1:54 PM | 2 kt SE | 3 kt | — | — |
| Tue 12:54 PM | 4 kt ESE | 5 kt | — | — |
| Tue 11:54 AM | 11 kt E | 12 kt | — | — |
| Tue 10:54 AM | 11 kt E | 13 kt | — | — |
| Tue 9:54 AM | 14 kt E | 16 kt | — | — |
| Tue 8:54 AM | 12 kt E | 14 kt | — | — |
| Tue 7:54 AM | 14 kt ENE | 19 kt | — | — |
| Tue 6:54 AM | 13 kt ENE | 16 kt | — | — |
| Tue 5:54 AM | 17 kt ENE | 19 kt | — | — |
| Tue 4:54 AM | 13 kt E | 17 kt | — | — |
Observed Tue 3:00 PM at NDBC buoy CSIM3 (Castle Island (NOS) 8444069), 4.9 miles away. Seas from buoy 44090 (Cape Cod Bay, MA (221)), 44.4 miles away, at Tue 3:00 PM.
Frequently asked questions
What is the marine forecast for Boston Harbor today?
This Afternoon: SE winds around 10 kt. Waves 2 to 3 ft. Patchy fog. A slight chance of showers.
Is there a small craft advisory for Boston Harbor?
No advisories, warnings or watches are in effect for NWS zone ANZ230 as of the last update on this page. Advisories can be issued at any time; check the current bulletin before leaving the dock.
How high are the waves at Boston Harbor right now?
Seas are running 2.0 ft at a 3-second period, measured at NDBC buoy CSIM3 Tue 3:00 PM, 4.9 miles from this zone. The forecast peaks at 2.0 ft Tue 3 PM.
What do the wind speeds in knots mean?
One knot is 1.15 mph. The National Weather Service issues a small craft advisory for sustained winds of roughly 22–33 knots or hazardous seas, a gale warning at 34–47 knots, and a storm warning at 48 knots and above. Exact advisory thresholds vary by forecast office and by water body — a bay reaches dangerous chop at a lower wind speed than open ocean.
Where does this forecast come from?
The forecast text is the National Weather Service's own marine bulletin for zone ANZ230, issued by Boston/Norton MA, reproduced in full. The wind and seas charts are drawn from the NWS gridded forecast for a point inside the zone. Observations come from the nearest reporting NDBC buoy. We are not affiliated with NOAA or the National Weather Service.
Forecast: NOAA/NWS product CWFBOX, issued Tue 1:04 PM. Observations: NOAA National Data Buoy Center station CSIM3, read Tue 3:00 PM. Retrieved Oct 13, 3:42 PM. Conditions offshore change faster than any page can be rebuilt, so check the current NWS bulletin and your own instruments before going out.