Traffic increases 18 percent over a five-year average on Saturday as Aug. 21 eclipse nears

August 20, 2017

Wyoming traffic counts continued to increase on Saturday, Aug. 19 over a five-year average, with the northwestern, western and southern parts of the state having the most increases as the Aug. 21 solar eclipse nears.

Traffic counts increased by more than 131,000 vehicles, or more than 18 percent when looking at a five-year average for the third Saturday in August.

All counties had increases in traffic on Saturday. The counties that had the most traffic increases on Saturday were in the northern, western and southern parts of the state and include Teton at 17,755 more vehicles, Sweetwater at 14,192 more vehicles, Uinta at 12,196 more vehicles, Fremont at 11,978 more vehicles, Carbon at 11,391 more vehicles and Lincoln at 6,790 more vehicles.

Laramie County also had a substantial increase of 12,174 more vehicles on Saturday. On Friday, the county had an increase of 2,542 more vehicles, Thursday had 5,175 more vehicles and Wednesday had 2,780 more vehicles.

Although WYDOT can’t say for sure that the increase is the result of the eclipse, it is a good indicator it’s the result of the solar event. The increases don’t consider vehicles that pass the same spot multiple times a day, like commuter vehicles or local delivery vehicles. The traffic counts also don’t reflect all traffic movement in the state as all roads don’t have counters.

Southern Wyoming

Traffic once again increased on US 287 south of Tie Siding near the Colorado border by 85 percent (4,402 more vehicles). Traffic has steadily increased on that road over the past three days with Wednesday and Thursday’s figures showing a more than 40 percent increase, and Friday’s around 60 percent.

Also in the southern part of the state, traffic on US 85 south of LaGrange increased by 63 percent (1,487 more vehicles) on Saturday. On Wednesday, traffic increased by 36 percent, Thursday by 40 percent and Friday by 50 percent.

Northwestern Wyoming

Traffic also continued to increase in the northwestern part of the state. On US 287 east of WYO 28 and Lander, traffic increased by 158 percent (1,685 more vehicles) on Friday. On Wednesday, traffic on that road increased by 22 percent, Thursday by 45 percent and Friday by 81 percent.

Traffic continued to increase locally in several spots. Those areas include Jackson, Afton, Etna and Moran Junction along US 89, 189 and 191, which are high-volume roads in the state.

Traffic counts for US 89 south of Etna increased by about 35 percent (2,019 more vehicles), figures indicated. On US 26-89-189-191 south of Kelly near Jackson, traffic increased by 29 percent (4,121 more vehicles).

Some other areas in the northwestern part of the state where traffic continued to increase included:

  • US 89-191-187 north of Moran Junction north of Jackson - 49 percent (2,358 more vehicles)
  • US 89-191-187 south of Moran Junction near Jackson - 45 percent (2,396 more vehicles)
  • US 89-191-187 near Colter Bay near the Grand Teton National Park - 35 percent (1,508 more vehicles)
  • US 189 north of Lazeart Junction near Evanston - 100 percent (1,181 more vehicles) – On Friday, traffic increased by 48 percent (710 more vehicles), Thursday by 22 percent (309 more vehicles) and Wednesday by 18 percent (244 more vehicles)
  • US 89 south of Afton - 43 percent (1,285 more vehicles)
  • US 189-191 at Teton National Park - 58 percent (1,363 more vehicles)


Traffic along Interstate 80 also had some increases on Saturday in the central and western parts of the state.

East of Evanston, traffic increased by 27 percent (4,530 more vehicles) and west of Evanston, traffic increased by 32 percent (6,485 more vehicles). West of Laramie on I-80, traffic increased by 28 percent (4,199 more vehicles). West of Rawlins on I-80, traffic increased by 21 percent (3,305 more vehicles). East of Little America on I-80, traffic increased by 18 percent (2,933 more vehicles), and west of Green River, traffic increased by 15 percent (2,717 more vehicles).

Along I-25, traffic increased dramatically on Saturday with percentages between 15 and 40 in some areas. On I-25 near the Colorado border, traffic increased on by 31 percent (7,749 more vehicles), which is higher than Friday’s figure of almost 13 percent (3,549 more vehicles). North of Horse Creek, traffic increased by 64 percent (7,305 more vehicles), which is higher than Friday’s figure of 24 percent of (3,386 more vehicles). At Central Avenue, traffic increased by only by 23 percent (4,511 more vehicles), which is higher than Friday’s figure of 7 percent (1,795 more vehicles).

Traffic on parts of I-90 in northern Wyoming also increased, but not as much as the other interstates. Those increases were between 5 and 10 percent.