Coming home last night from our vacation we were driving in rain from before Barstow on I-40, all the way down the I-15 into Orange Co. At times between the rain that was falling and spray being kicked-up by the trucks, we could barely see where we were going. There was one section of the I-15, a few miles before we merged onto the CA-91, that the road was flooded a couple of inches deep and it really slowed down the traffic. The water was about half-way across the road but you could see, from where the debris was, that earlier it was almost all the way across the roadbed.
Note that our final total, when we arrived at our house at about 8:12pm last night, was exactly 6001.0 miles that we had driven during this vacation. We drove across 11 states and made many stops to see the local sights (I'll try and post some photos later in the week).