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When should we write to you about Cerna?

No thresholds are published for Cerna, so we suggest thresholds based on the station’s history.

When should we write to you about Cerna?When the water is very low for the time of yearrecommended nowLower than in 9 out of 10 years on the same date. Today the threshold is 43 cm.When the water is very high for the time of yearHigher than in 9 out of 10 years on the same date. Today the threshold is 177 cm.A level you choosePick the level on the scale yourself, for example the level at which your dyke floods.

“Very low” and “very high” are recalculated every day from the station’s history, so the threshold rises in spring.

Choose above when we should write to you.