Heat in Natrona County Lower Elevations, Wyoming

The latter part of March was a record warm one for Natrona County. The two week period from March 17 to March 30 averaged almost 17 degrees above normal daily average temperatures; with all but two days at least 10 degrees above normal. Nine new daily record high temperatures were set. The old monthly second high temperature of 77 degrees was tied or broken six times, including four days in a row from March 18 to March 21. There were four high temperatures in the 80s, which were the first four occurrences of 80 degrees in March in station history. Records in Casper date back to 1940.

A very strong ridge of high pressure set up across much of the western United States and brought an long period of record breaking warmth. The most impressive stretch was from March 18 through March 21. In total, 71 new daily record high temperatures were set out of a possible 126 high temperatures at RIW CLI sites (longer term climate sites), greater than half of the daily highs. Every location was at least 10 degrees above normal through the period. Every location had their all time warmest period for these two weeks, with three locations; the Riverton Airport, the Sweetwater County airport near Rock Springs, and the Lander airport; more than 8 degrees above the previous warmest period. All locations set their all time high temperature March multiple times in this stretch. Six locations had their earliest 80 degree high temperature, with four stations having their first 80 degree or greater March high temperatures in station history.