The total solar eclipse of August 21 is almost upon the US.
Approximately 7.4 million Americans may travel to the path of totality, where the moon's darkest shadow will cut across the country. But this mass migration may overwhelm small towns and cities with record tourism — and choke key roadways with gridlock traffic.
That's according to an analysis by Michael Zeiler, a cartographer at the mapping data and technology company Esri, and an eclipse chaser of 26 years.
"People should not casually expect to drive down on the morning of the eclipse," Zeiler told Business Insider.
A video taken on Wednesday by a frustrated-sounding central Oregon resident, which KAPP-KVEW Local News posted to its Facbook page, shows a line of cars that stretches for all 4 minutes and 32 seconds of the video, and for about 4 miles of roadway.
"This is all heading into Prineville on a Wednesday, all the way up the mountain," she said in the video, which she recorded around 11:32 a.m. PDT. "There is no accident. This is all for the lovely eclipse that is happening, and everyone trying to get into their camping spots."
She added: "Luckily, I'm heading the other direction. ... The cars next to us are going roughly 5 miles per hour, if not completely stopped."
Prineville, Oregon, is located about 120 miles southeast of Salem, Oregon — a location that Zeiler expects to be one of the sixth-most trafficked solar eclipse viewing locations in the country.
Based on his analysis, about 25 million Americans may determine the Salem area is the quickest to reach and see totality. Most probably won't make that trip, but the Zeiler's maps nonetheless illustrate the potential chokepoint (and Prineville may see some runoff).
Traffic on main roadways throughout the region seemed to be decent on Friday morning, according to Google Maps data, but Zeiler expects most people to hit the roads this weekend — so mid-week traffic jams aren't an encouraging sign.
On the East Coast, the road to totality also seemed ominous.
"Driving from Charlotte to Nashville and there are a lot of advisory signs warning people about the eclipse," Bob Bryan, a policy reporter for Business Insider, told his colleagues in a chatroom message on Friday afternoon.
Zeiler advises those who are making the journey to bring all the food, water, toilet paper, and other essentials they would need in case small-town stores have their shelves emptied by hordes of eclipse chasers.
"You need to plan to be completely self-sufficient," he said.
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