Ice conditions

Normal situation Previous ice map Ice map of the previous year Icebreakers

Normal situation


The ice in the Bay of Bothnia is slowly drifting eastward.

In the northern Bay of Bothnia, off Tornio, there is 30-50 cm thick rotten fast ice to Tähti. Off the fast ice edge there is 10-45 cm thick ridged close and very close ice to Kemi 2. Farther south, mainly open water approximately to the line Merikallat - Farstugrunden. In the central Bay of Bothnia, approximately along the line Rödkallen - Merikallat, there is 15-40 cm thick open ice.

Northern Lake Saimaa is almost ice-free.

Icebreakers: Kontio assists in the Bay of Bothnia.

Restrictions to navigation: Minimum ice class and deadweight required of assisted vessels:
Tornio and Kemi, IA of more than 2000 tons.
Oulu, IA and IB of more than 2000 tons
Raahe, I and II of more than 2000 tons.

Vessels bound for Gulf of Bothnia ports in which traffic restrictions apply shall, when passing Svenska Björn, report their nationality, name, port of destination, ETA and speed to ICE INFO on VHF channel 84. This report can also be given directly by phone +46 31 699 100.

Vessels bound for Finnish or Swedish ports with traffic restrictions in the Quark or the Bay of Bothnia shall, 20 nautical miles before Nordvalen Lighthouse, report in accordance with the instructions for winter navigation to Bothnia VTS on VHF channel 67.

The reference map can be changed by clicking on the links above the images. The different maps show the average (= normal) ice conditions (1965-1986) for the period in question, the ice chart of the preceeding week, the corresponding ice chart for the previous year, and the current location of Finnish icebreakers.

The Baltic Sea Now pages display a simplified map of the sea areas by Finland. This map is updated weekly, by Tuesday morning at the latest. The map shows the areas covered by ice and the thickness of smooth ice in these areas. In addition, the map includes isometric displays of temperature gradients by area.

When the Baltic is not covered by ice, the maps show the surface water temperatures in the sea areas and the corresponding temperatures from the previous year. During ice-free periods, the maps are updated irregularly.

More information

Explanation of map's finnish words

  • jäätä: ice
  • vettä: water
  • normaalitilanne: normal situation
  • ahtauma: ice ridge
  • haurasta: rotten ice