When Does Mosquito Season Begin?

Mosquito season begins in the U.S. once the temperatures reaches 50 degrees Fahrenheit consistently.  Mosquito eggs that remained dormant during the winter will begin hatching and propagating.   Female mosquitoes that have spent the summer in protected areas like basements and trees are now ready to come out and lay their eggs. This map shows the average start time for mosquito season across the United States.   In some regions it starts as early as February!