Mosquito season in Cochise County, AZ: when it starts and ends
Mosquito months in Cochise County
In a normal year mosquito season in Cochise County, AZ starts around March 27 and ends around November 13, about 33 weeks.
- Jan
- Feb
- Mar
- Apr
- May
- Jun
- Jul
- Aug
- Sep
- Oct
- Nov
- Dec
What to do in Cochise County, and when
- Start tipping out standing water weekly by March 13.
- Book any yard treatment for late March, ahead of the July peak.
- Repellent can go away after November 13.
- 4 West Nile cases since 2016 (last 2024): you should use repellent at dusk June to September, more so if over 60.
Cochise County against the rest of AZ
Cochise County has the 9th longest season of 15 AZ counties, at 231 days against 364 in Maricopa County and 150 in Coconino County. Its mean temperature is 62.4°F.
- Pima County: March 6 to November 21 (260 days, 142 WNV)
- Graham County: March 13 to November 16 (248 days, 6 WNV)
- Yavapai County: April 13 to October 31 (201 days, 7 WNV)
- Greenlee County: April 21 to October 28 (190 days, 0 WNV)
West Nile in Cochise County
From 1999 to 2025, CDC ArboNET counted 10 human West Nile cases in Cochise County (6 neuroinvasive) across 7 years. The worst was 2020 with 2; the latest was 2024.
See how the dates are worked out, and reading the West Nile counts.