(NBC News) - The official start of summer is just a few weeks away, which also means another season is beginning: Mosquito season.
The pest control company Orkin recently ranked the top 20 mosquito cities based on the number of mosquito treatment requests they got in 2013.
"It was interesting because that list happened to mirror in many respects with what we saw nationally with rainfall totals in the US," says Orkin's Kim Kelley-Tunis.
More rain means more mosquitoes because the bugs like to breed in standing water, and when experts studied cases of West Nile virus, a potentially severe illness spread by mosquitoes, they found a certain area of the country tends to have the most cases.
"We kind of see almost the middle part of the US as being the highest risk area, so from Texas all the way up into the Dakotas we actually see really high incidence of it," says Dr. Kristy Murray of Baylor College of Medicine.
Experts are quick to say it's impossible to predict how severe West Nile season will be, but they are predicting a new virus, Chikungunya, will make an appearance within the next two years.
"With Chikungunya that's another one that's also a mosquito-borne disease that more than likely will be introduced here to the US and will be our West Nile, per se," Dr. Murray says.
Chikungunya was detected in St. Martin in December, the first time it had been found in the western hemisphere. Now several Caribbean countries have reported cases.