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 (yellow) is once a year, at the second risk level (orange) once in five years, and at the highest risk level (red) 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). The warning levels are set for the 14 observation stations.

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

Sea level warning limits

The warning limits are listed in the tables below referenced to the theoretical mean water (MW) and N2000 (BSCD2000) systems.

Theoretical mean water (MW)

Skip Sea level warning limits, theoretical mean water table
 
low
(yellow)
high
(yellow)
very high
(orange)
dangerously high (red)
Kemi, Oulu
-80 cm
115 cm
140 cm
170 cm
Raahe, Pietarsaari
-65 cm
85 cm
110 cm
130 cm
Vaasa
-50 cm
85 cm
110 cm
130 cm
Kaskinen, Pori, Rauma
-50 cm
75 cm
100 cm
120 cm
Föglö
-50 cm
65 cm
85 cm
100 cm
Turku, Hanko
-50 cm
70 cm
95 cm
110 cm
Helsinki, Porvoo
-60 cm
80 cm
115 cm
130 cm
Hamina
-70 cm
110 cm
145 cm
170 cm

N2000 (BSCD2000)

Skip Sea level warning limits, N2000 table
 
low
(yellow)
high
(yellow)
very high
(orange)
dangerously high (red)
Kemi, Oulu
-72 cm
123 cm
148 cm
178 cm
Raahe
-57 cm
 93 cm
118 cm
138 cm
Pietarsaari
-59 cm
 91 cm
116 cm
136 cm
Vaasa
-44 cm
 92 cm
117 cm
137 cm
Kaskinen
-41 cm
 84 cm
109 cm
129 cm
Pori, Rauma
-39 cm
 86 cm
111 cm
131 cm
Turku
-36 cm
 85 cm
110 cm
125 cm
Föglö
-39 cm
 76 cm
 96 cm
111 cm
Hanko
-32 cm
 88 cm
113 cm
128 cm
Helsinki, Porvoo
-39 cm
101 cm
136 cm
151 cm
Hamina
-49 cm
131 cm
166 cm
191 cm