The last few days of near constant rain has provided a very good time to check your reception under nominal conditions. With stable temperatures and no inversions signals should have been stable for days.
My temperature since mid Saturday has been 50F +/- 1 degree. I don't think I've ever seen such a small variation over almost 2 days. Signals have also been remarkably stable. I carefully monitored Sutro, Fremont and Salinas signals, especially UHF on the higher antennas. I can positively say that rain has no affect on the signals at all.
I, too, noted the stable temperature. I thought my thermometer was stuck, since it sat at 57 degrees night and day, but this morning it had dropped down to 53.
Signals were very steady here this past weekend, too, but I sure didn't get the great signals that you did. Some of your signals from Sutro are quite impressive! If anything, mine were below what I consider "normal". Only 31 and 58 were coming in from Walnut Grove. 3, 6, 10, and 13 were all below the cliff edge at about 13.5 dB SNR. KAXT 1 was hovering around the cliff edge at 16 dB. Signals from the other South Bay stations 14, 36, 48 and 54, 42 and 52 from Mt. Diablo and the three stations from up north, 22, 50 and 68, were all about a dB or two lower than normal. If these are the signals I get under nominal conditions, I must be experiencing the affect of inversion quite a bit of the time here, since the signals are usually higher.