
End of November
- Ice formation has started in the northernmost Bay of Bothnia and in sheltered bays there already is level ice up to 10 cm thick.
- The water temperature in the central Bay of Bothnia is over 3°C.
- Water temperatures in Sea of Bothnia are 3°…6°C.
- In the Northern Baltic Proper, water temperatures are over 7°C.
- In the Gulf of Finland water temperatures are in the range 1°–7°C.

End of December
- Along the coasts of Bay of Bothnia and off-shore in northern part, 5–20 cm thick ice and thin new ice. In Vaasa archipelago, ice is forming in sheltered bays.
- 2-10 cm thick ice in the easternmost parts of the Gulf of Finland, otherwise new-ice formation in the archipelago of the eastern Gulf of Finland.
- The water temperature in the central Bay of Bothnia is over 1°C.
- The water temperature in the central Sea of Bothnia is over 3°C.
- In the Northern Baltic Proper, water temperatures are over 6°C.
- In the Gulf of Finland water temperatures are in the range 1°–5°C.

End of January
- The central parts of the Bay of Bothnia are still ice free. Otherwise the Bay of Bothnia is frozen and ice occurs along all shores of the Northern Baltic Sea.
- In northern Bay of Bothnia, 20–50 cm thick ice. In central parts 5–30 cm thick ice.
- In the archipelagos of the southern Bay of Bothnia and the Quark, 10–30 cm thick ice.
- In the central Quark, thin ice.
- Along the coasts of the Sea of Bothnia, 5–20 cm thick ice.
- Thin ice in sheltered parts of the Archipelago Sea and the archipelago of the western Gulf of Finland.
- In the central Sea of Bothnia and central parts of the western Gulf of Finland, water temperatures are in the range 1°–4°C.
- In the Northern Baltic Proper, the water temperature is over 3°C.
- In the eastern Gulf of Finland, 5–30 cm thick fast ice, and thin ice in central parts.
Next update to the forecast will be issued in January 2023.
Contact: Finnish Meteorological Institute, Ice Service — iceservice@fmi.fi

Contact: Finnish Meteorological Institute, Ice Service — iceservice@fmi.fi
