We were in CA, in the Rv, during the last big El Nino in 97-98. We too were there for our first grandson. There were some very wet days when we stayed in campgrounds but there were also sunny days in between the rain storms.
We were in Anthony Chabot state park near Castro Valley (east SF Bay) when it was closed due to high winds producing falling limbs, and 101 was flooded 1-2ft deep south of Salinas for 10 miles or so, but those were one day events. Plenty of rain, some wind, but nothing so bad we had a multi day delay in traveling.
As mentioned watch the weather ahead and move accordingly. I have seen snow and ice on I-10 around Fort Stockton when I-40 between Amarillo and Albuquerque was clear, sunny, and dry.