If you're going to pin a mast, the Sierra foothills are the place to do it.  Not long ago I was researching the peak wind gust data that drives the engineering standards and it turns out that the Sierra foothills from Auburn south to Bakersfield is one of the most tower-friendly locations in the United States.  Extreme high winds (over 60 mph) are very rare.  There's a weather station near Cool and the highest peak wind gust in the last 10 years was only 50 mph.  The big exception to this is if you live on a hilltop, a ridge line or at the edge of a bluff, then you will see high winds due to the terrain speed-up effect.  Another exception are localized freak gusts, like a thunderstorm microburst -- but again, the odds of that happening on top of you are fairly small.

Interestingly, average wind and peak gusts are somewhat higher on the Sac or SJ valley floor than in the foothills.  Of course wind gusts are very high as you move uphill to the crest.

73 Jim K6OK