Aedes grossbecki is recognized as a mosquito of the southeastern United States, but the species is fairly well distributed in New Jersey. The mosquito occurs at low levels throughout the more southern counties of the state during the early Spring and larvae have been collected as far north as Morris County. Collection records from New York State show that the distribution of this species extends beyond the New Jersey border. In all probability, Ae. grossbecki exists at very low levels in all but the most northern counties of New Jersey. Aedes grossbecki is one of the earliest mosquitoes to hatch from overwintering eggs.
Development is rapid, considering the cold water that is present in the early Spring.
In southern New Jersey, the larvae reach 3rd instar during the middle of March and pupate during the 1st or 2nd week of April. In the northern range of its distribution, the larvae hatch with Aedes excrucians where both species reach 3rd instar in early April and pupate during the 3rd week of the month. Aedes grossbecki is on the wing before most mosquito control agencies put out their light traps, however, the species persists until early summer and is usually represented in low numbers in trap collections during May and June. The larvae of Ae. In southern New Jersey, Holly replaces Beech as an indicator and the larvae frequently occur in borrow pits where sand has been extracted for land fill.