Weather history and climate summary information is available for the following locations:
- Casper
- Cheyenne
- Sheridan
Warmest May Days
The warmest May days in Wyoming are:
| Sheridan, Wyoming | 1988 | 98.1°F |
| Casper, Wyoming | 2003 | 95°F |
| Sheridan, Wyoming | 2009 | 93.9°F |
| Sheridan, Wyoming | 2001 | 93°F |
| Casper, Wyoming | 1984 | 91.9°F |
Coldest May Days
The coldest May days in Wyoming were:
| Sheridan, Wyoming | 2005 | 16°F |
| Casper, Wyoming | 1953 | 16.3°F |
| Cheyenne, Wyoming | 1953 | 17.1°F |
| Casper, Wyoming | 2005 | 17.1°F |
| Casper, Wyoming | 1954 | 17.4°F |
Wettest May Days
The wettest single days in May occurred:
| Sheridan, Wyoming | 1973 | 5.1 inches |
| Sheridan, Wyoming | 2005 | 2.5 inches |
| Casper, Wyoming | 2007 | 2.2 inches |
| Casper, Wyoming | 1952 | 2.1 inches |
| Casper, Wyoming | 1991 | 2.1 inches |