We often think of October as the end of M&T season, think again.
Last year I had mosquitoes much later and ticks well into November in my yard.
Humans often encounter ticks (especially tiny nymphs) during leaf cleanup.
From Dr. Matt Frye:
In one week, mosquito eggs laid in a puddle, flower pot, bird feeder, kids toy or tarp can grow into biting adult mosquitoes. Where are mosquitoes breeding in your yard?