INDIANA, USA — May is typically the peak month for birds migrating north and passing over Indiana, however a huge surge of birds has recently flown over the Hoosier state thanks to strong south winds.
Over the past 3 nights (April 26-28) BirdCast estimates nearly 40 million birds have flown over Indiana. They use radar to estimate birds flying north, while ignoring meteorological data like rain. It cannot be exact but it gives an idea on how many are making that journey north.
Why are they surging north right now? Is this normal?
Very normal. Bird migration isn't very steady. It can be feast or famine, mainly due to the weather. Birds try to use a south wind to fly north. On days when the south wind is strong over the first few thousand feet of the atmosphere, they will take-off and start flying north.
Generally the peak for birds migrating north is May. But that doesn't mean every day in May has a bunch of birds. Breezy south wind days bring millions of birds either to or over Indiana. Some of them stop here, but many fly north into Michigan and Canada.
Recently we have had a strong high pressure ridge in the southeastern United States. On its western side, you see arrow pointing north. That's the general wind pattern going from south to north.
To the west there is a cold front. This low pressure storm system has brought multiple days of severe weather and tornadoes to the Plains. Ahead of the front, south winds have roared. This has created a wind tunnel for birds to hop into and make the journey north a bit easier.
You may have to wash your car more often the next 2-4 weeks as bird migration generally peaks over Indiana. It'll come in waves, so especially watch out on warm, windy days.
— 13News Meteorologist Matt Standridge
