This is actually the first time I looked very closely this year but it seems mosquitoes are starting to breed. I could see one 5 gallon bucket maybe 8 feet outside our back door had a whole bunch of larvae. Upon closer inspection a bunch of the other containers with water had them, too. Those containers have been drained.
I recommend everyone do the same. Check all containers with water for mosquitoes. Probably best to just drain all standing water and nip the problem in the bud.
Addendum: Realizing some might be storing water for use this summer, that presents a problem for mosquito control. You might try these mosquito dunks. They're a natural toxin that kill water borne larvae. I don't know if they still have them but Pierson's used to carry them years ago.