SIGMET of the Netherlands

A SIGMET is a warning for (large) aviation that reports on (un)foreseen dangerous weather conditions and should therefore be treated with priority. The area for which the KNMI issues a SIGMET is the Amsterdam FIR, including the concession area in the North Sea (North Sea Area V) and above FL100. A SIGMET can be issued at any time. The validity period of a SIGMET is maximal 4 hours for a regular SIGMET and maximal 6 hours for a SIGMET for Volcanic Ash.