Severe Weather

Kristy and Dalan are visiting from Rexburg before Blake leaves for the Army. It rained last night so I decided to look at the weather report. For some reason, there was a "Severe Weather Alert". Compare to Rexburg with no weather alert. Is an 63 degrees with an 80% chance of rain more severe than 37 degrees with a 60% chance of snow? Or are Southern Californians wimpier so it seems to like "Severe Weather"?