Mosquito season in Washington County, RI: when it starts and ends
Mosquito months in Washington County
In a normal year mosquito season in Washington County, RI starts around April 25 and ends around October 23, about 26 weeks.
- Jan
- Feb
- Mar
- Apr
- May
- Jun
- Jul
- Aug
- Sep
- Oct
- Nov
- Dec
What to do in Washington County, and when
- Start tipping out standing water weekly by April 11.
- Book any yard treatment for late April, ahead of the July peak.
- Repellent can go away after October 23.
- 1 West Nile case since 2016 (last 2021): you should use repellent at dusk July to July, more so if over 60.
Washington County against the rest of RI
Washington County has the 5th longest season of 5 RI counties, at 181 days against 195 in Bristol County and 181 in Washington County. Its mean temperature is 50°F.
- Kent County: April 19 to October 22 (185 days, 0 WNV)
- Providence County: April 20 to October 22 (185 days, 12 WNV)
West Nile in Washington County
From 1999 to 2025, CDC ArboNET counted 3 human West Nile cases in Washington County (1 neuroinvasive) across 3 years. The worst was 2021 with 1; the latest was 2021.
More: how the dates are worked out · when the season starts across the US.