Mayfly hatch is about the same every year. Numbers will vary year to year, but you won't notice much if any difference in the overall numbers. Wind direction makes a difference in how many people see in any particular location. A north wind blows a lot more to shore. A south wind keeps more out on the Lake. One area may see a lot while 10 miles away it's much less. Once the water temperature gets to the right temperature (forgot what that is), they start hatching out and generally lasts about three weeks, with a peak in the middle.

There are aquatic insect hatches all season, from April through October. Late spring / early summer is the peak.