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Copernicus Emergency Management Service - CEMS > European Flood Awareness System > EFAS + JRC_Aug2023.png

Two layers show the probability of exceeding the 5-year return period in the EFAS forecasts at different lead time ranges:

5-year exceedance < 48 h indicates the probability of flooding in the following 48 h, a lead time range for which formal notifications are not issued.

Copernicus Emergency Management Service - CEMS > EFAS 5-year exceedance probability > 5yr_lt48h_legend.png

Figure 1. Example of the layer 5-year exceedance < 48 h on the forecast of July 2 2024 at 12 UTC.

5-year exceedance > 48 h indicates the probability of flooding from lead time 2 to 7 days, when formal notifications are issued.

Copernicus Emergency Management Service - CEMS > EFAS 5-year exceedance probability > 5yr_gt48h_legend.png

Figure 2. Example of the layer 5-year exceedance > 48 h on the forecast of July 2 2024 at 12 UTC.

Note. For an explanation on the computation of total probabilities, see this link.