My wife was a 30 year educator. So, our timing for spring RV trips was out of our control. Several times our departure was delayed by snow or we had to cut it short a day or two to run ahead of a incoming storm. One spring we had almost 5' of snow. Couldn't get the RV out of storage. What a pain.
Now that we are retired we pick a departure date and start to monitor the weather. We still often leave a day or two early or late to get ahead of the storms, but there is no pressure.
Each year we seem to leave a little earlier for Arizona. Our limiting factor is the heat. We watch to see when the heat breaks. This year it was still pretty hot when we arrived in Tucson in mid November. On the return we start watching the Colorado weather around mid March to look for a weather window. We have a couple of hunker down places between AZ and CO in case of bad weather.