Historically, the average date of the first 70 degree day of spring is April 18. But occasionally, that first 70 degree day comes as much as a month early.
Over the past 137 years of record keeping, there are 25 days in March to have reached 70 degrees and these are scattered in only 13 years. In every case, the 70 degree day in March has happened because of an early snow melt and a warm, dry weather pattern.
Each of the last two springs has delivered a 70 degree day. A record six days in the 70s happened in 2012. There were two in 2003 for a total of ten March days in the 70s already during the 17 years of this century. During the entire 20th Century, there were only 15 of 70 degree weather during March.
This is yet another illustration of how our warming climate is more likely to produce warm weather extremes.
