13 hours 12 minutes
An interesting weather week was finishing up on this date in 1976. It started with an inch or two of snow on Monday. But by the 17th a heat wave that developed in the middle of the country headed east, pushing temperatures into the 80s, reaching 90 degrees in many locations by the 18th and 19th. Burlington set its all time April maximum of 91 degrees, while Vernon soared to 97.