Cooler weather may slow down, but it won't stop the mosquitoes that carry West Nile virus. The chances of getting the sustained freezing temperatures needed to kill mosquitoes are about 50/50 in September.
So, the Front Range remains at the peak of the mosquito season as the number of West Nile cases continues to climb. Experts say the mosquito season usually ends in late September, when teh females that carry the virus stop laying their eggs.
There are 884 confirmed cases in Colorado including 11deaths.
Larimer, Pueblo, Boulder, Weld and Adams counties are the ones most affected. Starting Monday, Larimer County will begin aerial sprays of insecticide. They will do one application Monday, and another scheduled for Thursday.
Larimer County has the second highest number of human west nile cases in the state with 136. Weld County has the most with 160 of the state's total 884 cases. Eleven people have died from the virus.