A unique natural phenomenon is flying across the front range this weekend.

The annual migration of the Painted Lady butterfly is at its peak!

The species migrates more than 9,000 miles each year, from California to Mexico.

Several 9NEWS viewers sent us e-mails, photos and videos about the spectacular event.

Did you see them? Submit your photos here!

According to scientists at Colorado State University, the size of the annual migrations are dependent on the spring rains. In favorable years, there will be thousands and thousands of butterflies migrating across generations.

Painted Lady butterflies are very common across North America and you will likely see some in your garden this week! They love flowers and thistles.

Click here for more on the Painted Lady Butterfly.