University of Washington meteorology professor Cliff Mass talks about gusts on his blog and starts to explain why the westerlies are so exciting as you get closer to the town side of the Bay.

Last night I was sitting at my desk enjoying the sound of the winds..and it was quite an audio treat. I would hear the rumble in the distance. It would get closer and closer. Then the house and trees would shake.

As all of you know, the wind is almost never constant, with ebbs and flows. As a result, meteorologists often talk about sustained winds and wind gusts.

Sustained winds are the winds averaged over a period of time, typically two minutes. Gusts are the maximum winds (or actually maximum three-second winds for NWS sensors) during some period (often the same as the sustained winds).

Wind gusts can be a LOT stronger than the sustained winds…a typical value is 30-40% stronger, but on occasions it can be more. Here is an example at the UW for the last 24-h–look at the top row which shows both sustained winds and gusts.
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