With the wiped-out pickup as a cautionary tale, I slowed further. I got behind some big rigs that were grinding their way uphill for a while. As near as I can make it out, there were two sets of tire tracks straddling the three lanes of freeway here, and things got a little confusing. Some other vehicles with more stomach for higher speeds passed me, and I pulled out from behind the big rigs and followed them up the hill at about 35 MPH.
As I climbed higher, the snow began to stick some more. I found myself following a van driving even more slowly than me. At one point, I thought about trying to pull out and pass, even though at that point, there were no obvious ruts in the left lane. About that time, I felt the rear end of the van break loose slightly. Fortunately, I was going less than 25 MPH, and I had been reviewing skid-control tactics as I ground my way north. I did not touch the brakes, but let off the gas and the incipient skid corrected itself. The vehicle ahead of me also wobbled a couple of times and I decided that 25 was more than prudent.
Somewhat to my surprise, the snow turned back into rain at Weed, then almost stopped completely and the road cleared. I was able to gradually work my way back up to full freeway speed until just before Yreka, when the slushy stuff began to fall again. I pulled into the hotel in Yreka just as it looked like the stuff was starting to stick to the road a bit.
I was monitoring the automated road condition radio frequency through this part of the mountains, and if I heard right, they put "R1 modified" (chains required for vehicles towing trailers) on I-5 just behind me at Weed a few minutes after I went through. I'm not towing, but if the snow continues the way it was when I went through, they'll be upgrading the restrictions soon enough. If I hadn't been able to get away from the Bay Area as early as I did, I might have been caught out and have to chain up.
My hotel room is quite familiar, as I've stayed in this exact room before. here's a picture from my previous stay. And after that slog through the snow, a soak in the hot tub sounds like a good idea to me.
The weather forecast for tomorrow morning is rain and snow, with snow at the higher elevations. I just hope it isn't enough to put chain restrictions over Siskiyou Pass or the other Southern Oregon passes tomorrow.