After a severe storm, mosquito populations can explode, and the diseases they carry can be a danger to humans. Mosquito problems occur in two distinct waves after a flood. The first to arrive are the flood water mosquitoes, which include the salt marsh (Aedes taeniorhynchus, Aedes sollicitans) and pastureland mosquitoes (Psorophora columbiae, Psorophora cyanescens, Aedes vexans). These mosquito species deposit their eggs on the soil in areas that are flooded periodically. When flooded, the eggs hatch 5 to 7 days later, resulting in large swarms of mosquitoes during the warmest times of the year.