About 100 million Americans face power blackouts this summer as roasting weather, overstretched powerplants and unreliable green energy sources combine to create a perfect storm of problems.
States stretching from the Great Lakes to the Pacific Ocean which are home to tens of millions of Americans could have a hard time producing enough power for their residents this summer.
The 'MISO' part of America's power grid - whose full name is the Midcontinent Independent System Operator is at greatest risk of a large-scale outage.
Also at the highest risk are Louisiana, Mississippi, Arkansas and a small part of East Texas. That high-risk classification means that the existing power grid is 'potentially insufficient to meet peak load during both normal and extreme conditions,' according to NERC.
Every state that sits further west of that area is at an elevated risk, according to NERC. That means power plants should have sufficient resources 'to meet peak load during normal conditions, but potentially insufficient during extreme conditions.'
And large parts of the elevated risk areas saw just those conditions last summer, with normally temperate Oregon and Washington enduring temperatures that soared close to 120f for days on end.
High temperatures will drive people to crank their air conditioners and use up more energy. That puts a strain on existing power grids - and environmental as well as economic factors could make that energy hard to come by.
Parts of the Midwest will experience a 'capacity shortfall' driven by increased demand and power plant shutdowns as states turn to more renewable energy sources like hydro and solar.
But those energy sources could be hampered by the weather, as droughts in California and the Pacific Northwest are expected to limit the output of hydroelectric dams.