Warnings on the sea water level

On the basis of the sea water level observations made, the warning limits have been set so that the frequency of warnings at the lowest risk level is once a year, at the second risk level once in five years, and at the highest risk level once in 20 years.

Only one warning level is used for low water (yellow), but all three warning levels are used for high water (yellow, orange and red).

Warnings for sea level are drawn up for periods of up to 5 days.

The warning limits are listed in the table below:

 low water   high watervery high waterdangerously high water
 once a yearonce a yearonce in five yearsonce in 20 years
 yellowyelloworangered
Northern Bay of Bothnia-80115140170
Southern Bay of Bothnia-6585110130
The Quark (Vaasa)-5085110130
Sea of Bothnia-5075100120
Sea of Åland and Archipelago (Föglö)-506585100
Sea of Archipelago (Turku), Western Gulf of Finland (Hanko)-507095110
Western Gulf of Finland (Helsinki, Porvoo)-6080115130
Eastern Gulf of Finland-70110145170

Photo: Eija Vallinheimo