Re: Averaging wind speed in tropical and extra-tropical storms


I'm not sure which buoys you are talking about here,
but the NOAA ones have sensors nowhere near 30m.  More
like 10 at most -- and those are the big disc buoys
in the middle of the gulf.

See, for example

<http://www.ndbc.noaa.gov/station_page.php?station=42001>
<http://www.ndbc.noaa.gov/station_page.php?station=42003>


Scott

Shawn Delaney wrote: 
The height on the bouys that are used run about 30m which the frictional
effects of land can be assumed to be nil...on land the wind sensors at most
airports sits ~6m of the gorund in which case would yield different wind
speeds. Hurricane tracking software is now incorporating frictional effects
as the storms approach land and do a fairly good job of accounting for
terrian effects.
"Øyvind Seland" <oyvindse@xxxxxxxxxxxx> wrote in message
news:dgr6tk$vq2$1@xxxxxxxxxxxxxxxx

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










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