Typical late spring/early summer cloudy day in the SF Bay area. This is on the road leading up to Fremont Peak. The clouds look formidable but typically they do not rise much more than 2000-2500 feet. By the time we make it up to the top of Fremont Peak, we should be well above the cloud tops.
Once the road reaches higher elevations, the clouds are left behind. The SF Bay area commonly has low clouds that may extend only 1000 to 2000 ft to their tops. We usually call these clouds the "marine layer" since it blows in from the Pacific Ocean.
Approaching the park at the end of the road we can finally see off to the west toward the Pacific Ocean. The clouds blow in from the ocean and usually are dense but hug the ground. With an elevation nearly 3000 feet, the area used for astrophotography in the Fremont Peak State Park usually is comfortably above the clouds. But not always.
The wide angle rig is now set up and in position for imaging in the Southern Sky. The quarry tonight will be the Rho Ophiuchus nebulous region near Antares
And an image taken before thin and high clouds shut down the night's activities prematurely. And so it goes On Fremont Peak....
The image was 3 x 10 minutes of Halpha.