Mosquito season in Tooele County, UT: when it starts and ends
Mosquito months in Tooele County
In a normal year mosquito season in Tooele County, UT starts around April 28 and ends around October 12, about 24 weeks.
- Jan
- Feb
- Mar
- Apr
- May
- Jun
- Jul
- Aug
- Sep
- Oct
- Nov
- Dec
What to do in Tooele County, and when
- Start tipping out standing water weekly by April 14.
- Book any yard treatment for late April, ahead of the July peak.
- Repellent can go away after October 12.
- No West Nile cases since 2016, so bites in Tooele County are a nuisance; check window screens.
Tooele County against the rest of UT
Tooele County has the 12th longest season of 29 UT counties, at 167 days against 210 in Salt Lake County and 82 in Summit County. Its mean temperature is 52.7°F.
- Carbon County: April 24 to October 15 (174 days, 0 WNV)
- Cache County: April 27 to October 12 (168 days, 22 WNV)
- Beaver County: April 30 to October 14 (167 days, 0 WNV)
- Box Elder County: April 30 to October 9 (162 days, 11 WNV)
West Nile in Tooele County
From 1999 to 2025, CDC ArboNET counted 8 human West Nile cases in Tooele County (4 neuroinvasive) across 4 years. The worst was 2006 with 3; the latest was 2011.
Background: when the season starts across the US; how the dates are worked out.