Ocean waves in the evening sky.

my sister and I were at a shopping mall and I took this picture from the parking lot. We noticed the unusual wavy cloud pattern and the soft pink glow from the sunset. It was both beautiful and mesmerizing. What kind of cloud pattern is this and what makes the clouds appear wavy?

I used my personal iPhone SE with no special lens or attachments.

I cropped off the bottom of the photo to eliminate an annoying lit sign which distracted from the beauty of the sky.