wa to fl in dec via I-5 to I-10

West Texas can see some single-digit lows along I-10 in the winter. Sometimes the highs won't get above freezing, either. Just to keep in mind for your fresh water system.

Rob

If the weather is iffy the OP could cut over to 101 around Drain. Chances of snow on 101 are pretty minimal.

So many variables coming down the 5 from weather, detours, wildfires and LA, that my advice is take it slow and expect all the problems. This way if they happen, it's all expected and part of the plan. But, if nothing happens, you'll be very happy.

As for I-10, the only parts you need to plan for is from Palm Springs CA to San Antonio TX. Lots of long empty (not lonely) stretched with services spaced apart. Plan your trip with stops and services taken into consideration.

Now, this is the most important item to pay attention to: The "THING" is not something you need to stop and see. Despite all the signs and hoopla, drive on by!

I would keep an eye on weather.
South on I-5 can be a real bear over the Siskiyous. Starts around Ashland, OR and can continue to Redding, CA.
You may think about I-90, I-82, I-84 to I-15 in Utah. Yes, there is or could be more mountains to cross. Or I-90, I82, I-84 to Twins Falls, ID then south on US-93.
With the fires and the like in CA, it could be more difficult.
Yes, make sure you "carry" chains. I for one would stop well before needing to install them. OR is only one of the northwest states that require them. Traction devices
Vehicle combinations over 10,000 must follow this.
Over 10,000 pounds

thanks for the info donn0128

You should expect snow from home to Redding. After that you should be fine. Remember, ODOT requires you to carry chains or have traction devices in the mountains. If your towing you will also need drag chains. Towing speed limit in CA is 55MPH.