Mosquito season in Millard County, UT: when it starts and ends
Mosquito months in Millard County
In a normal year mosquito season in Millard County, UT starts around May 7 and ends around October 5, about 22 weeks.
- Jan
- Feb
- Mar
- Apr
- May
- Jun
- Jul
- Aug
- Sep
- Oct
- Nov
- Dec
What to do in Millard County, and when
- Start tipping out standing water weekly by April 23.
- Book any yard treatment for early May, ahead of the July peak.
- Repellent can go away after October 5.
- 1 West Nile case since 2016 (last 2017): you should use repellent at dusk July to August, more so if over 60.
Millard County against the rest of UT
Millard County has the 18th longest season of 29 UT counties, at 151 days against 210 in Salt Lake County and 82 in Summit County. Its mean temperature is 50.9°F.
- Weber County: May 5 to October 7 (155 days, 15 WNV)
- Emery County: May 4 to October 5 (154 days, 1 WNV)
- Daggett County: May 10 to October 3 (146 days, 0 WNV)
- Morgan County: May 10 to October 1 (144 days, 0 WNV)
West Nile in Millard County
From 1999 to 2025, CDC ArboNET counted 1 human West Nile case in Millard County (1 neuroinvasive) across 1 year. The worst was 2017 with 1; the latest was 2017.
See how the dates are worked out, and when mosquitoes go away for the winter.