The ice in the Bay of Bothnia slowly drifts southward.
In the northern Bay of Bothnia there is 30-50 cm thick fast ice in the archipelago. Farther out 15-45 cm thick, rafted and in places ridged, very close ice, approximately to the line Malören - Marjaniemi. There are fractures in the ice field. Farther out in places thin drift ice and new ice.
In the southern Bay of Bothnia there is 10-30 cm thick fast ice in the archipelago. In places brash ice barriers at the ice edge. Off the archipelago, thin open ice.
In the Quark there is 15-25 cm thick fast ice in the inner archipelago. Off Ensten there is a narrow brash ice barrier. Farther out open water.
In the Sea of Bothnia there is 5-25 cm thick ice in the archipelago.
In the Gulf of Finland there is 5-20 cm thick fast ice in the inner archipelago. In the outer archipelago there is thin very open ice. In the Gulf of Vyborg and off St. Petersburg there is 5-30 cm thick very close ice approximately to the line Halli - Sosnovyj Bor. Farther out, new ice and open ice to Motschnyi.
Icebreakers: Otso, Kontio and Polaris assist in the Bay of Bothnia.
Restrictions to navigation: Minimum ice class and deadweight required of assisted vessels:
Tornio, Kemi and Oulu, IA of more than 2000 tons.
Raahe and Kalajoki, IA and IB of more than 2000 tons and IC and II of more than 3000 tons.
Kokkola, Pietarsaari and Vaasa, I and II of more than 2000 tons.
Kotka and Hamina, I and II of more than 2000 tons.
Alterations to the restrictions: Minimum ice class and deadweight required of assisted vessels from 27th January:
Kokkola, Pietarsaari and Vaasa, IA and IB over 2000 tons and IC and II over 3000 tons.
Vessels bound for Gulf of Bothnia ports in which traffic restrictions apply shall, when passing the latitude 60°00'N, report their nationality, name, port of destination, ETA and speed to ICE INFO on VHF channel 78. This report can also be given directly by phone +46 31 699 100.
The ice chart of the whole Baltic Sea (pdf) is published in the autumn twice a week (Monday and Thursday) and daily when the amount of ice increases until until ice break-up in spring. It represents current ice situation, ice breaker positions and traffic restrictions in the Baltic Sea.
The simplified charts are updated once a week at the latest on Tuesday morning. The first one represents measured level ice thicknesses, ice coverage and sea surface temperature. The reference charts represent average, 1965 – 1986, ice situation on that day (= normaali), last week´s situation, last year´s situation and the positions of the ice breakers.
Explanation of chart's finnish words