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Old March 26th 08, 11:48 PM posted to uk.sci.weather
Bernard Burton Bernard Burton is offline
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First recorded activity by Weather-Banter: May 2004
Posts: 5,382
Default Highly variable wind direction today

Only one complete revolution here on the sonic, Stephen.
That was between 1745 and 1830.
1745 360
1750 210
1800 180
1815 070
1830 360

The rest of the time since 1530 the direction varied between 210 and 060,
veered and backed through 360.
Wind speed during the revolution was 0.5 to 2.0 kn.



--
Bernard Burton
Wokingham, Berkshire, UK.

Satellite images at:
www.woksat.info/wwp.html
or
www.btinternet.com/~wokingham.weather/wwp.html
wrote in message
...
Whoops. Pressed return too quickly ... take 2

My wind directions today (vector mean wind direction 5 mins ended on
the hour):

0900 213 degT - SSW
1000 218 - SW
1100 287 - WNW
1200 320 - NW
1300 237 - WSW
1400 165 - SSE
1500 288 - WNW
1600 080 - ENE
1700 212 - SSW
1800 192 - SSW
1900 357 - N
2000 236 - WSW

On the dd plot it looks like four complete revolutions through 360
degrees since 1430 today. Winds light but not zero: gust 16 kn 1429
associated with heavy rain shower accompanied by hail.

Until I got my first AWS back in 1993 I had no idea that changes of
wind speed and direction were this sudden or relatively frequent.
Today is quite exceptional but it's astonishing how variable the wind
really is (both direction and speed, and combined) when you examine
the record in detail.

--
Stephen Burt
Stratfield Mortimer, Berkshire