This is an archived article that was published on sltrib.com in 2015, and information in the article may be outdated. It is provided only for personal research purposes and may not be reprinted.

Power outages affected nearly 12,200 homes and businesses along the Wasatch Front as Monday dawned.

Rocky Mountain Power crews faced their largest outages — which left a combined 9,837 in the dark — in Midway, Park City and rural Summit County. In Park City, the power failure left traffic signals dark, prompting police to issue warnings to motorists.

Those electrical customers, residing in the 84049, 84060 and 84098 zip codes, had their power back by 10 a.m.

Another 1,432 RMP customers were without power in the 84121 zip code, comprising Salt Lake City, Big Cottonwood Canyon and Brighton. They were back in service by 9 a.m.

Erda, Grantsville and Tooele combined had 914 out of service, but crews had them back on the grid by 9:15 a.m.

Causes of the outages were under investigation, RMP officials said.

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