Air more turbulent in the evening on 880 in Bay Area?

[cv_rider]

When I take the bike to meetings, I normally go south on 880 from the Hayward area to San Jose, sometime in the morning. Returning in the afternoon, I find the air more turbulent. Wind noise is greater, and the bike gets buffeted around a bit more. This is a pretty consistent phenomen. Has anyone else ever noticed it?

I wonder what causes it. I've been thinking something like the air heats up during the day and that somehow makes it less smooth. Sounds a bit weak, but can't think of anything better. Traffic conditions are more or less the same on both legs of the journey.

 

[damnpoor]

It's always like that. In the evening the wind coming in off the bay picks up. I work at Moffett and there is always a wind in the afternoon coming straight off the water. When I used to fly out of Reed-Hillview it was always bumpier in the afternoon.

 

[CHEMIKER]

It's always that way for me too. I work near Moffett too (we should have lunch damnpoor), and we get some pretty good winds in the afternoon coming off the water.

The rumor I heard is that it's due to the air inland being hotter than the air offshore, causing a convection and drawing air inland, resulting in evening breeze.

 

[cv_rider]

Makes sense. I notice that the wind, at any time of the day, is worst on the 237. I suppose there must be a constant wind coming off the "Bay" (aka muddy marsh) just north of it. Never much care for riding the 237 'cause of that (but the carpool lane is more effective there than any other freeway I ride). I've done all kinds of things to reduce wind noise by making air flow smoothly around my helmet, but it doesn't work if the air is inherently turbulent.

 

[steveindenmark]

This happens everywhere and I think it has something to do with the air cooling down.

This may be total nonesense but it makes sense to someone who is not a meteo...meoter....weatherman.

Steve