NEWPORT BEACH (CBSLA) – The Southland is experiencing a rare sighting this week: about 1 billion butterflies swarming the skies during their migration from Mexico to the Pacific Northwest.

The Painted Ladies have been spotted from San Diego to Pasadena. Californians took to social media to share pictures of the orange, black and white insects.

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“Everyone was posting about the butterflies all over Instagram,” one woman said. “I saw so many, it was kinda like a swarm of them. It was pretty insane.”

Scientists say the migration isn’t new, but they haven’t seen numbers like this in almost 15 years. The reason, scientists say, is because of the unusual amount of rain in Southern California recently. The butterflies now have plenty of flowers and leaves to feed on.

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Last year, scientists feared a butterfly catastrophe as numbers of the magical insect took a nosedive. Researchers counted only 25,000 migrating Painted Ladies. This year, they estimated more than one billion.

“I think it’s really neat just because everyone can really see the effects of how much rain we’ve been getting,” another woman said.

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The Painted Ladies are expected to traverse the state over the next several days.