Rolling blackouts from Texas deep freeze extend to eastern Montana Rolling blackouts in southern U.S. causing outages in Montana By: Jon Stepanek and last updated 2021-02-17 12:12:40-05 BILLINGS â Even mighty Texas, the energy powerhouse of America, is feeling the wrath of Mother Nature. And the consumption of power throughout the nationâs midsection during an unprecedented cold snap is causing rolling blackouts as far north as Eastern Montana. Two Montana electric cooperatives, NorVal and McCone, both had brief rolling blackouts Tuesday related to the southern winter storms, which affected hundreds of customers. NorVal Electric Co-op serves about 1,925 customers in the Opheim-Glasgow area, while McCone Electric's service area includes 14,400 square miles stretching from Miles City to Glendive to Wolf Point, then west to Cat Creek.