Mosquito season in Rich County, UT: when it starts and ends
Mosquito months in Rich County
In a normal year mosquito season in Rich County, UT starts around May 30 and ends around September 11, about 15 weeks.
- Jan
- Feb
- Mar
- Apr
- May
- Jun
- Jul
- Aug
- Sep
- Oct
- Nov
- Dec
What to do in Rich County, and when
- Start tipping out standing water weekly by May 16.
- Book any yard treatment for late May, ahead of the July peak.
- Repellent can go away after September 11.
- No West Nile cases since 2016, so bites in Rich County are a nuisance; check window screens.
Rich County against the rest of UT
Rich County has the 27th longest season of 29 UT counties, at 104 days against 210 in Salt Lake County and 82 in Summit County. Its mean temperature is 39.6°F.
- Sevier County: May 26 to September 29 (126 days, 1 WNV)
- Piute County: May 31 to September 23 (115 days, 0 WNV)
- Wasatch County: June 8 to September 20 (104 days, 0 WNV)
- Summit County: June 19 to September 9 (82 days, 0 WNV)
West Nile in Rich County
CDC ArboNET lists no human West Nile cases for Rich County from 1999 to 2025, though virus turned up in birds, mosquitoes or horses in 2 of those years.
More: how the dates are worked out · when the season starts across the US.