Rainwater pools, and those pools become standing water. Mosquitoes breed in that standing water, and their eggs hatch about a week later.
It’s not your imagination. The worst mosquito stretches really do tend to follow a little after a rainy spell. Rain doesn’t so much bring out the mosquitoes as it sets the next batch in motion.
Mosquitoes have a very simple survival tactic. Step one: lay drought-resistant eggs in damp, low-lying areas. Step two: wait for water to rise. That’s all they need to hatch. A big storm will flood the zones, then mosquitoes will be born, and heat speeds the entire cycle up.
And at the same time, new standing water sources will be created by rainwater filling up clogged gutters and containers left outside in the yard. All can become sources of new mosquitoes within a week.
A heavy downpour can flush some larvae out of moving water like ditches and streams, which is why a single hard rain occasionally seems to help for a day. But, of course, that very same storm will fill up every still, low-lying site, and those are the ones that matter when it comes to mosquito breeding. So the net effect is “better tomorrow, worse in a week.”
No matter what, the main thing you can do to combat mosquitoes is dump standing water within a few days of rain. This denies mosquitoes easy breeding sites. The other piece is to have a professional barrier treatment applied to your property.
If you're tired of every rainy week being followed by an unusable yard, Mosquito Squad of South Metro Minnesota can help. This is done through the application of a barrier treatment that helps protect your yard with up to 90% reduction in mosquito activity, refreshed every 21 days by a trained technician through the season.
