Hi all,

I'm in the process of building an anemometer and I'm trying to work out what
kind of results I would like from it.

I'm obviously going to want average wind speed and gust wind speeds but I'm
not sure what kind of time range averages should be taken over and what the
official definition of a gust wind speed is.

I've seen official sites talking about 10 minute averages and 1 minute
averages. Is there a specific time duration of set of durations that I
should be averaging over?

Is a gust speed measured over any time interval at all or is it just
determined by how quickly the anemometer cups can respond to a sudden
increase in wind speed. If this is the case doesn't that make a wind gust
rather subjective as your measurement will depend on your model of
anemometer?

Any help appreciated, or feel free to point me at a relevant web site if
there is one.

Cheers
David

For synoptic observations in the UK, wind is measured over 10 minute
intervals, and the gust reported is the highest (taken as 3 second reading
if the instrument has faster response than this) in the past synoptic
interval, 6 hours for the main synoptic hours 00, 06 etc, 3 for the
intermediate synoptic hours, 03, 09 etc, and 1 hour at other times. For
Metars the definition is different for gusts, but the direction and speed is
still the 10 minute mean. the gust in this case is the highest in the same
10 minutes.
Anemometers are exposed at a standard height of 10 metres, and should be
corrected to this height if exposed at a different one.
For climatological purposes, I personally archive hourly mean wind speed and
direction, and highest gust in that hour.
Don't forget thaty wind is a vector quantity, and means must be calculated
from the individual components (E-W, S-N), and not from the directions.
--
Bernard Burton
Wokingham, Berkshire, UK.

Satellite images at:
www.btinternet.com/~wokingham.weather/wwp.html
"David Parker" wrote in message
...
Hi all,

I'm in the process of building an anemometer and I'm trying to work out
what
kind of results I would like from it.

I'm obviously going to want average wind speed and gust wind speeds but
I'm
not sure what kind of time range averages should be taken over and what
the
official definition of a gust wind speed is.

I've seen official sites talking about 10 minute averages and 1 minute
averages. Is there a specific time duration of set of durations that I
should be averaging over?

Is a gust speed measured over any time interval at all or is it just
determined by how quickly the anemometer cups can respond to a sudden
increase in wind speed. If this is the case doesn't that make a wind gust
rather subjective as your measurement will depend on your model of
anemometer?

Any help appreciated, or feel free to point me at a relevant web site if
there is one.

Cheers
David