After seeing thousands of painted lady butterflies a couple of weeks ago, I thought they were done for the season.Painted Ladies migrate across North America!
Wrong! There are still so many migrating through the Denver area, that, when they fly a bit higher, they are visible on radar!
NWS BoulderVerified account @NWSBoulder Oct 4 4/4: Migrating butterflies in high quantities explains it. Today, the butterflies are staying close to the ground. #cowx #Science
How cool is that?
Colorado In Depth and At Altitude 
I read something from a Butterfly Pavilion employee that said it wasn’t a migration, but a large population due to favorable conditions. Did you see that?
I think what they are really saying is that we have Painted Ladies migrating through every year, but this year the population exploded due to favorable conditions. Here are two good articles:
http://www.denverpost.com/2017/09/20/painted-ladies-butterflies-front-range/
http://www.dailycamera.com/boulder-county-news/ci_31314792/flood-painted-lady-butterflies-enrich-boulder-countys-late
Whenever I go outside, I am blown away by their sheer numbers in the garden. A guaranteed smile every. single. time.
” A guaranteed smile every. single. time.” Love it.
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