On the NOAA webpage I noted that the classification on hurricane strength was based on
wind speed averaged over 1 minute. At least in Europe classification of wind speeds in extra-tropical
storms call for a 10 minute average. Going from 10 to 1 minute average may yield a quite large
increase in wind speed, depending on the nature of the storm and terrain. I suppose for
a tropical storm over ocean, it is probable not that large variation? For an extra-tropical
storm over hilly terrain, the effect may be going from a strong gale to close to hurricane wind speed
Are there no agreed on definition of wind speed?



Øyvind Seland