If gnats fly in compact bodies in the beams of the setting sun, expect fine weather.
If many gnats are seen in the spring, expect a warm autumn.
When gnats dance in March it brings death to sheep. (Dutch.)
Hornets.
Hornets build nests high before warm summers.
When hornets build their nests near the ground, expect a cold and early winter.
House Flies.
House flies coming into the house in great numbers indicate rain.
Harvest Flies.
When harvest flies sing, warm weather will follow.