Ice conditions

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

Normal situation


The ice condition is virtually unchanged.

In the northern Bay of Bothnia 30-60 cm thick fast ice in the archipelago. Off the fast ice there is ridged, 20-45 cm thick compact drift ice to approximately 6 nautical miles southwest of Bothnia buoy. The ice field is in places difficult to force. Farther out thin very close ice.

In the southern Bay of Bothnia in the archipelago 25-45 cm thick fast ice. Off the fast ice there is open water and very open ice. Farther out offshore and Sweden's side 10-30 cm thick ice with varying concentration.

In the Quark 20-40 cm thick fast ice in the archipelago. Farther out open water or very open ice. From east of Norrskär to Nordvalen there is 2-5 nautical miles wide zone of close ice.

In the Sea of Bothnia 10-35 cm thick fast ice in the archipelago. Farther out in places drifting floes and shuga.

In the Archipelago Sea thin ice in the inner archipelago. In the fairways mostly open water or very open ice.

In the western Gulf of Finland thin fast ice in the inner archipelago. Further out there is thin very open ice.

In the eastern Gulf of Finland 15-40 cm thick fast ice in the inner archipelago. Farther out some drifting floes. In the Gulf of St. Petersburg and the Gulf of Vyborg, 20-40 cm thick ice. Farther out 5-25 cm thick ridged consolidated ice.

Icebreakers: Kontio, Otso, Sisu and Frej assist in the Bay of Bothnia. Zeus assists in the Bay of Bothnia as well as in the northern Sea of Bothnia. Voima assists in the Gulf of Finland.

Restrictions to navigation: Minimum ice class and deadweight required of assisted vessels:
Tornio, Kemi, Oulu and Raahe, IA of more than 4000 tons.
Kalajoki, Kokkola, Pietarsaari and Vaasa, IA and IB of more than 2000 tons.
Kaskinen, Loviisa, Kotka and Hamina, IA and IB of more than 2000 tons and IC and II of more than 3000 tons.
Kristiinankaupunki, Pori, Rauma, Uusikaupunki, Naantali, Turku, Taalintehdas, Förby, Hanko, Koverhar, Inkoo, Kantvik, Helsinki and Sköldvik, 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.

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