Colorado mosquito forecast, by town

A daily mosquito bite-risk score for all 343 Colorado towns, grouped by their 64 counties. Mosquito pressure is local, so pick your town for today's number, a 7-day outlook, and what's driving it.

Adams County · 14 towns

Alamosa County · 3 towns

Arapahoe County · 20 towns

Archuleta County · 1 towns

Baca County · 6 towns

Bent County · 1 towns

Boulder County · 11 towns

Broomfield County · 1 towns

Chaffee County · 3 towns

Cheyenne County · 2 towns

Clear Creek County · 5 towns

Conejos County · 5 towns

Costilla County · 2 towns

Crowley County · 4 towns

Custer County · 2 towns

Delta County · 6 towns

Denver County · 1 towns

Dolores County · 2 towns

Douglas County · 17 towns

Eagle County · 10 towns

El Paso County · 18 towns

Elbert County · 4 towns

Fremont County · 9 towns

Garfield County · 8 towns

Gilpin County · 2 towns

Grand County · 6 towns

Gunnison County · 5 towns

Hinsdale County · 1 towns

Huerfano County · 2 towns

Jackson County · 1 towns

Jefferson County · 19 towns

Kiowa County · 3 towns

Kit Carson County · 6 towns

La Plata County · 3 towns

Lake County · 2 towns

Larimer County · 7 towns

Las Animas County · 6 towns

Lincoln County · 4 towns

Logan County · 6 towns

Mesa County · 10 towns

Mineral County · 1 towns

Moffat County · 2 towns

Montezuma County · 4 towns

Montrose County · 4 towns

Morgan County · 5 towns

Otero County · 6 towns

Ouray County · 2 towns

Park County · 2 towns

Phillips County · 3 towns

Pitkin County · 2 towns

Prowers County · 5 towns

Pueblo County · 5 towns

Rio Blanco County · 2 towns

Rio Grande County · 3 towns

Routt County · 4 towns

Saguache County · 4 towns

San Juan County · 1 towns

San Miguel County · 5 towns

Sedgwick County · 3 towns

Summit County · 7 towns

Teller County · 3 towns

Washington County · 2 towns

Weld County · 27 towns

Yuma County · 3 towns

Colorado mosquito questions

What kinds of mosquitoes live in Colorado?
Colorado has floodwater mosquitoes (the dominant summer nuisance biter, which surges after heavy rain), the Asian tiger mosquito (a daytime biter that breeds in yard containers), the house mosquito (the main West Nile carrier), and swamp and cattail-marsh mosquitoes tied to the EEE cycle. Which ones dominate a given town depends on its local breeding habitat.
When does mosquito season start and end in Colorado?
In Colorado, mosquito numbers build from about mid-June, peak in mid-to-late summer, and fade with the first cool nights of fall. Biting largely stops once temperatures drop below about 50°F, and a hard freeze ends the season.
Is West Nile or EEE a risk in Colorado?
Both West Nile virus and Eastern equine encephalitis occur in the region, but human cases are rare. West Nile risk peaks in late-summer heat and tracks the house mosquito in developed areas; EEE rises after mid-July in swampy areas. For confirmed local activity, check the Colorado health department's arbovirus surveillance.
How do I keep mosquitoes out of my yard in Colorado?
The single biggest thing you control is standing water: empty anything that holds it, keep gutters clear, and change bird baths weekly. Use EPA-registered repellent at dawn and dusk, and for heavy biting a licensed mosquito-control service can treat breeding sites and resting spots you can't reach.