If you’ve spent any amount of time outside during a summer in Arizona, you already know how frustrating mosquito season can be. Whether you’re walking the dog in Gilbert or relaxing by the pool in Chandler, it seems like mosquitoes are always ready to ruin your day.
So, when do they actually go away in Arizona—and why do they hang around so long?
In this article, we’ll cover when mosquito season typically ends and what factors keep mosquito activity going longer than you’d expect.
Key Takeaways
- Mosquito season in Arizona usually ends in late October or early November when nights finally cool down.
- Warm weather, rain from the monsoon season, and standing water keep mosquito breeding going in cities like Phoenix.
- Different mosquito species and leftover water in flower pots or gutters can stretch mosquito problems into fall.
- Regular pest control and removing standing water help stop mosquitoes from spreading and protect your family.
When Is Mosquito Season Over in Arizona?
Mosquito season in Arizona typically starts winding down in late October or early November. That’s when overnight temperatures begin to consistently drop below 50°F—too cold for adult mosquitoes to remain active.
But in cities like Phoenix, Mesa, and Scottsdale, warm temperatures can linger, dragging the season out longer than you’d hope.
Of course, the exact timing depends on a few key conditions that we’ll walk through next.
Temperature and Climate Conditions
Arizona’s desert climate creates a unique environment for mosquitoes. High summer temps may drive them to hide during the day, but once the sun goes down, mosquito activity can surge—especially if there’s been recent rain.
After the monsoon season, when humidity spikes and puddles stick around, mosquito breeding increases across Maricopa County.
Once nighttime lows drop into the 40s, mosquito breeding slows down.
Female mosquitoes can’t lay viable eggs, and larvae don’t survive the cold, which brings the season to an end.
Standing Water and Mosquito Breeding Grounds
Mosquitoes need stagnant water to reproduce. Even small amounts—like what collects in bird baths, clogged gutters, flower pots, or a forgotten water can—can serve as a breeding ground. And it’s not just after rainstorms.
Sprinklers, leaky hoses, and poorly drained landscaping in places like Chandler and Mesa can all create ideal mosquito breeding conditions.
This is why your swimming pool, if left uncovered or untreated, could be contributing to a mosquito infestation well into the fall.
Urban Heat Islands and Water Sources
Phoenix and other large cities in Arizona act as urban heat islands, where concrete and asphalt keep surfaces warm even after sunset. This can support higher mosquito populations longer into the season.
Combined with abundant water sources like irrigation runoff, ornamental ponds, or even moisture-trapping trash bins, these areas stay active breeding zones for longer than you’d expect.
Species of Mosquitoes
Different species of mosquitoes behave differently.
In Arizona, Aedes aegypti—also called the yellow fever mosquito—is one of the most aggressive. It bites during the day, prefers living near people. It is also known for spreading mosquito-borne diseases like the Zika virus, dengue fever, and chikungunya. It can continue to lay eggs even in cooler weather if the environment stays warm and wet enough.
Meanwhile, Culex mosquitoes, which transmit West Nile virus and encephalitis, tend to be more active at dusk and dawn.
Lack of Mosquito Control Efforts
If you’re not actively managing your yard, mosquitoes will stick around longer than they should. Standing water isn’t always easy to spot—it hides in toys, plant saucers, clogged drains, and low-lying corners of the yard. Without regular pest control, you could be unknowingly supporting a full-blown mosquito infestation.
EPA-recommended insect repellent with DEET, long sleeves, and outdoor sprays can help protect you from mosquito bites, but they don’t stop breeding.
Professional mosquito control focuses on both adult mosquitoes and larvae, helping prevent outbreaks and protect your family from mosquito-borne illnesses.
End the Mosquito Season at Home
Don’t let the mosquito problem overstay its welcome.
At Green Home Pest Control, we offer comprehensive mosquito control services across Phoenix, Scottsdale, Chandler, Gilbert, and the rest of Maricopa County. Our combination of monthly fogging and environmentally friendly treatments targets mosquitoes at every stage—from larvae to adult mosquitoes.
Even better?
Our system holds up during and after rainfall, making it ideal during Arizona’s unpredictable monsoon season. and enjoy a mosquito-free season—finally.
21 years of pest control experience
Founder and Owner of Green Home Pest Control
13 year resident of Arizona
