She told reporters she was terrified, calling this her worst nightmare come true.
She captured the moment on her phone while driving on the highway.
The snake can be seen hanging on the windshield and side-view mirror, while leaning its head on the driver's window.
Eventually, the driver made it safely off the highway and into a parking space where the snake got down and slithered away.
She said she thinks it came from a rural farm in Oklahoma, where she had been visiting friends.
An expert said it looks like a bull snake, which is not poisonous.
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