Casco Bay
Small Craft Advisory in force. Today: NE winds 10 to 15 kt, increasing to 15 to 20 kt late this morning and afternoon. Gusts up to 30 kt. Seas 4 to 6 ft. A chance of rain late this morning and early afternoon. Rain likely late. Vsby 1 to 3 NM this afternoon.
Casco Bay on the map
The zone and the zones around it, tinted where a marine warning or advisory is in force. Tap a neighboring zone to open its forecast.
- Storm Warning
- Gale Warning
- Small Craft Advisory
Now
The nearest stations reporting each, as of Sat, Sep 26, 10:00 AM EDT.
- Wind
- N 13 kt, gusts 17 kt at CASM1
- Water
- 59°F at CASM1
Alerts in force
Small Craft Advisory from Sat, Sep 26, 2:22 AM EDT until Mon, Sep 28, 8:00 AM EDT
Small Craft Advisory issued September 26 at 2:22AM EDT until September 28 at 8:00AM EDT by NWS Gray ME
The full text
* WHAT...Northeast winds 15 to 25 kt with gusts up to 35 kt and seas 3 to 6 ft. * WHERE...Penobscot Bay and Casco Bay. * WHEN...Until 8 AM EDT Monday. * IMPACTS...Conditions will be hazardous to small craft.
Inexperienced mariners, especially those operating smaller vessels, should avoid navigating in hazardous conditions.
The forecast
Coastal Waters Forecast from National Weather Service Gray ME, issued Sat, Sep 26, 8:03 AM EDT, valid until Sat, Sep 26, 9:00 PM EDT. Wind in knots, seas in feet.
SMALL CRAFT ADVISORY IN EFFECT THROUGH MONDAY MORNING
- Today
- NE winds 10 to 15 kt, increasing to 15 to 20 kt late this morning and afternoon. Gusts up to 30 kt. Seas 4 to 6 ft. A chance of rain late this morning and early afternoon. Rain likely late. Vsby 1 to 3 NM this afternoon.
- Tonight
- NE winds 15 to 20 kt with gusts up to 35 kt. Seas 4 to 6 ft. Rain. Vsby 1 to 3 NM.
- Sunday
- NE winds 20 to 25 kt with gusts up to 35 kt. Seas 4 to 6 ft. Rain. Vsby 1 to 3 NM in the afternoon.
- Sunday night
- NE winds 20 to 25 kt, diminishing to 15 to 20 kt after midnight. Gusts up to 35 kt. Seas 4 to 6 ft. Rain. Vsby 1 to 3 NM.
- Monday
- NE winds 15 to 20 kt with gusts up to 30 kt. Seas 3 to 5 ft. Rain. Vsby 1 to 3 NM.
- Monday night
- NE winds 15 to 20 kt with gusts up to 25 kt, diminishing to 5 to 10 kt after midnight. Seas 3 to 5 ft. Rain. Vsby 1 to 3 NM in the evening.
- Tuesday
- N winds 5 to 10 kt. Seas 2 to 4 ft. A chance of rain in the morning.
- Tuesday night
- NW winds around 5 kt. Seas 2 to 4 ft.
- Wednesday
- W winds around 5 kt, becoming S around 5 kt in the afternoon. Seas 2 to 3 ft.
- Wednesday night
- SW winds around 5 kt. Seas 2 to 3 ft.
Synopsis
Synopsis for Stonington ME to Merrimack River Ma out to 60 NM
A nor'easter continues gradually tracking toward New England and lingers south of New England through the weekend and possibly into Monday of next week. The nor'easter is forecast to lift northeast near or across the Gulf of Maine early next week before high pressure returns toward midweek. A front may approach from the west by late next week.
Buoys and stations nearby
The latest report from each station within reach of the zone, nearest first. Distances in nautical miles from the middle of the zone.
| Station | Distance | Wind | Waves | Water | Air | Pressure | Reported |
|---|---|---|---|---|---|---|---|
| CASM1 8418150 - Portland, ME | 9 nm | N 13 kt, gusts 17 | 59°F | 62°F | 1015.7 hPa | Sat, Sep 26, 10:00 AM EDT | |
| 44007 PORTLAND - 12 NM Southeast of Portland,ME | 12 nm | NNE 19 kt, gusts 23 | 58°F | 59°F | 1015.9 hPa | Sat, Sep 26, 10:10 AM EDT | |
| 44032 Buoy E01 - Central Maine Shelf | 31 nm | NE 19 kt, gusts 23 | 58°F | Sat, Sep 26, 10:00 AM EDT | |||
| WEXM1 Laudholm Farm, Wells Reserve, ME | 31 nm | N 8 kt | 61°F | Sat, Sep 26, 10:00 AM EDT | |||
| 44030 Buoy B01 - Western Maine Shelf | 36 nm | N 21 kt, gusts 25 | 60°F | Sat, Sep 26, 10:00 AM EDT | |||
| CMLN3 Coastal Marine Lab, New Castle, NH | 48 nm | SE 19 kt | 59°F | Sat, Sep 26, 9:01 AM EDT |
The past year
Warnings, watches and advisories the National Weather Service issued for this zone over the past 12 months, from the Iowa Environmental Mesonet’s archive.
| Product | Issued | Most recent |
|---|---|---|
| Gale Warning | 21 | Thu, Jun 18, 2026, 12:00 PM EDT |
| Special Marine Warning | 4 | Thu, Aug 13, 2026, 3:15 PM EDT |
| Storm Warning | 2 | Mon, Feb 23, 2026, 7:00 AM EST |
| Freezing Spray Warning | 1 | Fri, Jan 23, 2026, 10:00 PM EST |
| Gale Watch | 11 | Thu, Jun 18, 2026, 11:00 AM EDT |
| Tornado Watch | 1 | Thu, Jun 18, 2026, 1:45 PM EDT |
| Small Craft Advisory | 72 | Fri, Sep 25, 2026, 11:00 AM EDT |
| Freezing Spray Advisory | 9 | Sun, Mar 1, 2026, 9:00 PM EST |
What this means
Marine forecasts give wind in knots (1 knot is 1.15 mph) and seas in feet, except the high seas forecasts, which give seas in meters. Seas are the significant wave height, the average of the highest third of the waves; individual waves may be more than twice that. On the Great Lakes the forecast gives waves, not seas. "Wave Detail" splits the seas into the wind waves and each swell, with its direction and period.
Each coastal office writes a Coastal Waters Forecast for the bays, sounds and ocean out to 20 to 60 nautical miles, or on the Great Lakes a Nearshore Marine Forecast within 5 nautical miles of shore; the Open Lakes Forecast covers the rest of each lake. The Ocean Prediction Center and the National Hurricane Center write the Offshore Waters Forecasts out to about 250 nautical miles, and the High Seas Forecasts beyond. Forecasts are issued at least twice a day and updated when they go wrong.
- Small Craft Advisory
- Winds or conditions hazardous to small boats. The thresholds are set by each NWS region: typically sustained winds or frequent gusts of 20 to 25 knots up to 33 knots, and seas of 5 to 7 feet or more.
- Gale Warning
- Sustained winds or frequent gusts of 34 to 47 knots, not from a tropical cyclone.
- Storm Warning
- Sustained winds or frequent gusts of 48 to 63 knots, not from a tropical cyclone.
- Hurricane Force Wind Warning
- Sustained winds or frequent gusts of 64 knots or more, not from a tropical cyclone.
- Special Marine Warning
- A thunderstorm or squall over the water with winds or gusts of 34 knots or more, hail of 3/4 inch or more, or a waterspout, for up to two hours.
- Hazardous Seas Warning
- Wave heights or steepness at or above the office’s warning threshold, when the wind alone does not warrant a warning.
- Heavy Freezing Spray Warning
- Spray freezing on a vessel at 2 cm (3/4 inch) an hour or more.
- Tropical Storm and Hurricane Warnings
- Tropical storm (34 to 63 knots) or hurricane (64 knots or more) conditions expected within 36 hours. Watches: possible within 48 hours.
Nearby
- Coastal Waters from Port Clyde, ME to Cape Elizabeth, ME out 25 NM
- Coastal Waters from Cape Elizabeth, ME to Merrimack River, MA out 25 NM
- Waters from Cape Elizabeth ME to Merrimack River MA from 25 to 60 NM
- Waters from Port Clyde ME to Cape Elizabeth ME from 25 to 60 NM
- Coastal Waters from Stonington, ME to Port Clyde, ME out 25 NM
- Penobscot Bay
- Waters from Stonington ME to Port Clyde ME from 25 to 60 NM
- Ocean Waters from the Merrimack River to Plymouth from 40 to 60 NM
- Coastal waters east of Ipswich Bay and the Stellwagen Bank National Marine Sanctuary
- Intra Coastal Waters from Schoodic Point, ME to Stonington, ME
Open the live map with marine zones and buoysThe hour-by-hour forecast for the middle of the zoneCumberland Area BeachesSagadahoc Area BeachesEvery Atlantic Coast zone
Sources
Coastal Waters Forecast CWFGYX from National Weather Service Gray ME, issued Sat, Sep 26, 8:03 AM EDT. Original at NWS. Buoy reports from the National Data Buoy Center. Past products from the Iowa Environmental Mesonet. Zone outlines from the NWS marine and offshore zone boundaries. Warnings and advisories from the NWS API, read 14:49 UTC. All public domain, from the National Weather Service.