Mainly clear, SSE 13 kt, seas 3.0 ft, fog in play.
Today's brief
Every reading on this page, read together and written out in plain English.
Elevated fog risk from 6:00 PM to 2:00 PM tomorrow. Warm air over cold water — the classic Casco Bay setup. Carry radar and sound your horn.
Around 6:00 PM the breeze opposes the current. Seas will stand up short and steep — worse than the 2.5 ft height suggests, especially at the harbor entrance.
SSE 13 kt, gusts 15 around 6:00 PM.
Cold-shock response is real here. Wetsuit recommended; survival time 1–6 hours.
Starts 7:01 PM, sunset 7:41 PM, civil dusk 8:11 PM. Day length is shrinking by 3 min a day right now.
NNE 7 kt, 1.4 ft seas, flood tide. Best combination of breeze and sea state in the next 24 hours.
Tide
NOAA station 8418150 · Portland · heights above MLLW
Tidal current
Predicted flow through the two gates that matter. Flood sets into the bay, ebb runs out.
Portland Harbor Entrance
CAB1401Chandler Cove, South Entrance
CAB1409Sun and moon
13h 54m of daylight, losing 3 min a day
Sun is 24.3° above the horizon, bearing 265° (W).
Hour by hour
Wind, sea, tide, current and visibility on one timeline. Scroll sideways for the next two and a half days.
Sea state
Measured at NDBC 44007, 10.5 NM out — the real thing, not a model.
Long, organised energy from distant weather. Rolls under a boat rather than slapping it.
Built by today’s breeze. Short and steep — this is the part that makes a ride wet and uncomfortable.
Profiles show ~240 ft of ocean at 10× vertical exaggeration, so the two components can be compared at a glance.
Force 4 · Moderate breeze — small waves, frequent whitecaps. On land: dust and loose paper lift.
| Station | Wind | Seas | Period | Water | Air | Age |
|---|---|---|---|---|---|---|
Portland 44007 10.5 NM | S 10g12 | 3.0 | 5s | 60° | 64° | 30m |
Western Shelf 33.5 NM | S 10g14 | 2.6 | 5s | 66° | 68° | 1h 50m |
Jeffreys Ledge 54.2 NM | — | 2.6 | 4s | 68° | 68° | 20m |
Jonesport 128 NM | SSE 10g12 | 2.6 | 6s | 56° | — | 30m |
Best time to go
Every hour of the next day scored for what you actually want to do out there.
Fish feed hardest when the moon is on the meridian — overhead or underfoot — and around moonrise and moonset. Stack a major period on top of a running tide and that is your window.
The week ahead
Seven days of weather, sea, tide and moon. Wave heights run out past two and a half days — that is the honest limit of the marine model.
- Wind
- S 16 ktg26
- Seas
- 3.0 ft
- Rain
- 17%
- UV
- 0.8
- Wind
- NNE 8 ktg12
- Seas
- 2.1 ft
- Rain
- 8%
- UV
- 1.9
- Wind
- SSW 10 ktg14
- Seas
- 2.2 ft
- Rain
- 8%
- UV
- 6.7
- Wind
- NE 7 ktg9
- Seas
- 1.7 ft
- Rain
- 12%0.08"
- UV
- 5.8
- Wind
- SE 9 ktg10
- Seas
- —
- Rain
- 4%
- UV
- 6.1
- Wind
- S 8 ktg13
- Seas
- —
- Rain
- 17%
- UV
- 4.8
- Wind
- SSE 9 ktg11
- Seas
- —
- Rain
- 41%0.17"
- UV
- 5.3
Official forecast
NWS Gray, Maine · zone ANZ153 Casco Bay · issued 5:02 PM EDT
High pressure slides south into midweek, with a cold front approaching the waters Wednesday evening. High pressure then returns for the end of the week.
S winds 5 to 10 kt, becoming SE after midnight, then becoming NE towards daybreak. Seas 2 to 3 ft. Patchy fog this evening. Areas of dense fog after midnight. Vsby 1 NM or less.
NE winds around 5 kt. Seas around 2 ft. Areas of fog in the morning with vsby 1 NM or less.
E winds around 5 kt, becoming NW after midnight. Seas 2 to 3 ft. Patchy fog. Vsby 1 NM or less.
SW winds around 5 kt, becoming S in the afternoon. Seas 2 to 4 ft.
S winds 5 to 10 kt, becoming W after midnight. Seas 2 to 3 ft.
NW winds around 5 kt, becoming S in the afternoon. Seas 2 to 3 ft.
SW winds around 5 kt, becoming N after midnight. Seas around 2 ft.
NE winds around 5 kt, becoming SE in the afternoon. Seas around 2 ft.
S winds 5 to 10 kt, becoming NE after midnight. Seas around 2 ft.
Water temperature
The number that decides how long you have if you end up in it.
Cold-shock response is real here. Wetsuit recommended; survival time 1–6 hours.
Air quality
Ozone and fine particulate over the bay.
Aurora watch
Geomagnetic activity, and whether it is worth looking north.
Casco Bay sits near 53° magnetic latitude, so the northern lights generally need Kp 6 or better to show above the horizon — and you need to get clear of Portland’s glow. Chebeague, Cliff and the north shore of Bailey are the places to try.
24-hour peak Kp 3.7 · last reading 2:00 PM EDT
Freshwater in
What the rivers are pushing into the bay right now.
High flow after rain drops surface salinity, cuts water clarity and carries stormwater bacteria into the inner bay for a day or two. It also stratifies the top few feet colder and fresher near the river mouths.
Portland Harbor station
NOAA station 8418150, on the waterfront. Sheltered readings — a fair bit lighter than the outer bay.