UPDATE, Oct. 2017. The best resource for current wind patterns now seems to be sailflow. A detail of a screen capture from the site is shown above.
The USGS webpage referenced below from the original publication of this post in 2007 has been discontinued “due to lack of support and redirection of research efforts”—which seems a shame. The site now redirects to a San Jose Meteorology department page. As of today that site does not seem to be functioning. I hope that this information gets back up online soon. We could certainly use it in view of this season’s devastating fires. If anyone knows of better resources, please leave info in the comments.
Original post from Oct. 2007:
Here’s an unusual and interesting resource. The U.S. Geological Survey has a website that shows current wind conditions around the San Francisco Bay Area (they are considering a predictive model as well). There are two or three visualizations available, including the very cool flash “streaklines” (which unfotunately I can’t display here, and which might not work on some systems).
In the visualization above, the arrow size indicates exact speed (in knots, which are equal to 1.15 mph or 1.85 kph), while the color shows a certain range of speed. Speeds are at 10 meters and directions from true north. You can see that this morning there were strong winds blowing toward the Golden Gate from Marin, across midpeninsula, and at Mount Diablo.