Arizona Mosquito Forecast
Arizona's dry climate — only about 8" of rain a year — keeps mosquito pressure low across most of the state. Numbers climb mainly around irrigated land, standing water near towns, and the days right after a storm, rather than statewide.
Tap any city on the map above, or open the full Arizona map →
When is mosquito season in Arizona?
Arizona's mosquito season runs from March or April into October or November. Activity ramps up once overnight lows hold above about 50°F, and surges in the two to three days after rain, when fresh standing water triggers a new hatch. Long dry spells keep a lid on numbers between rain events.
Where are mosquitoes worst in Arizona?
Within Arizona, the most consistent pressure tends to land around Phoenix, Tucson, and Mesa. In a dry state, the standing water mosquitoes need is concentrated in cities — irrigation, lawns, retention ponds, stormwater — so the metros read higher than the open country around them. Anywhere near rivers, marshes, lakes, or recent flooding will read higher than the surrounding area — exactly the kind of local detail the live map above is built to show.
How the Arizona forecast works
MosquitoCast estimates Arizona's mosquito activity from live weather — temperature, humidity, wind, and recent rainfall — layered on the area's long-term rainfall climate, elevation, and terrain, and refreshed every day from NOAA's forecast data. It's the same model nationwide, so the reading for Arizona is directly comparable to anywhere else in the country.