Growing by the Bay

Category: weather

San Francisco Bay wind patterns

San Francisco Bay Area wind patterns

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.

For air quality information, air now is better than spare the air.

Original post from Oct. 2007:

san francisco bay area wind patternsHere’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.

California Rises from the Drought

This Nasa “video” is really a slideshow. You might want to turn the music down or off. Cool photos from space though.

Rain rain rain!

strange weather

Strange weather

Carol is thinking it might be too early this year to start our tomatoes.

It’s been cold and rainy for many days, and there is no break in sight. Last night there was spectacular thunder and lightning, which is rare in the Bay Area, and even a water spout over the ocean and a small tornado in Santa Rosa. We looked outside last night to see a winter wonderland, even though it should be spring here by the bay.

We’ve lived in the SF Bay Area since the 1970s, and only occasionally have we seen hail blanket the ground like this — and we’ve never seen it linger this way. The ground was cold enough that it didn’t melt for hours.

I know this won’t look like much to folks back east. Hey, I lived in Wisconsin once upon a time. But it’s damned strange for us here. It continues to rain as I write. They say more hail could be on its way tonight or tomorrow. And on it goes …

Running hot and cold

We have had weird swings this spring and summer between long chilly stretches and brief scorching temperatures.

The reason is clear: the ice caps are melting, and as a result our weather is bipolar.


San Francisco Climate

The best summary seems to be via Golden Gate Weather Services.

san francisco rainfall by month

Golden Gate Bridge in the fog

Cold ocean fog gets sucked through the Golden Gate, the narrow opening to the bay. The bridge that connects San Francisco at the south with Marin County at the north, though the second longest suspension bridge in the country, is only about 1.7 miles long, including the portions that extend over land. The narrowness of the Golden Gate prevented the immense bay (not nearly so large today as it used to be) from being discovered by early European explorers. When the fog would lift, Angel Island would create the illusion of a solid landmass.

The concentrated fog often takes weird winding routes through the city, contributing to its pronounced microclimates. One neighborhood can be warm and sunny while a neighboring one is suffused with a penetrating chill. This video was shot from a helicopter over the bridge.

Record Cold

It’s freezing — literally. Over here in the East Bay we’re looking at a week of lows around or under the freezing mark. I’ve been watering my plants and covering them with plastic at night when I can. But I don’t have enough plastic (or time) for all of them. My fuschias and brugmansias are looking very distressed. I can replace the fuschias since they grow fairly fast (and I think they might come back), but I’d hate to lose the big beautiful brugmansias.

The Bay Area gets frosts occasionally, bt it’s unusually to have such a long duration of frost. We are going to lose a lot of our semi-tropical plants. This is a sad development.

link: Tom’s Garden

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