Mosquito season in Delaware County, OK: when it starts and ends
Mosquito months in Delaware County
In a normal year mosquito season in Delaware County, OK starts around April 3 and ends around October 30, about 30 weeks.
- Jan
- Feb
- Mar
- Apr
- May
- Jun
- Jul
- Aug
- Sep
- Oct
- Nov
- Dec
What to do in Delaware County, and when
- Start tipping out standing water weekly by March 20.
- Book any yard treatment for early April, ahead of the July peak.
- Repellent can go away after October 30.
- 1 West Nile case since 2016 (last 2024): you should use repellent at dusk June to September, more so if over 60.
Delaware County against the rest of OK
Delaware County has the 72nd longest season of 77 OK counties, at 210 days against 271 in Choctaw County and 193 in Cimarron County. Its mean temperature is 58.5°F.
- Blaine County: April 3 to November 4 (215 days, 1 WNV)
- Ellis County: April 5 to November 4 (213 days, 2 WNV)
- Harper County: April 7 to November 1 (208 days, 3 WNV)
- Texas County: April 8 to November 1 (207 days, 4 WNV)
West Nile in Delaware County
From 1999 to 2025, CDC ArboNET counted 4 human West Nile cases in Delaware County (2 neuroinvasive) across 4 years. The worst was 2024 with 1; the latest was 2024.
Background: when the season starts across the US; how the dates are worked out.