A few times per year, the analysed low level winds, eg 10m winds, become very large in a particular location, which varies amongst a few apparently preferred locations. The largest values seen so far are about 300 ms-1.
From 19 February 2020, the ERA5 system examines the 10m wind components and if the magnitude of either component exceeds 50 ms-1, then the analysed parameters are replaced with the "4v" parameters. These latter parameters are similar to the analysed ones, but don't usually suffer from such large values.
The tables below, for January 1979 to December 201918 February 2020, give details when the 10m wind components of the 10m winds, the 10 metre U wind component and 10 metre V wind component, exceed 50 ms-1. This value is an arbitrary one, which may capture real wind events, such as hurricanes and typhoons.
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