The Midcontinent ISO on Oct. 28 released its winter readiness assessment for the 2026-2027 winter season, highlighting a sufficient capacity outlook and coordinated preparedness efforts to support reliable electric service across the region.
"Preparing for winter starts well before temperatures begin to drop," said Tim Aliff, MISO’s executive director of market operations. "This year's assessment reflects the ongoing work of MISO and our member utilities to bring new resources online, plan for a range of operating conditions and support reliable electric service throughout the season."
The region enters the winter season well-positioned to meet expected electricity demand. MISO’s annual Planning Resource Auction secured approximately 134.7 gigawatts (GW) of winter capacity offers, exceeding the projected winter peak demand of approximately 113.4 GW, the grid operator said.
Approximately 3.6 GW of new capacity additions were offered into the auction for this winter season, led by natural gas resources and supported by coal, wind, solar and battery storage additions.
Imports from neighboring systems rose by roughly 1 GW, while suspensions and retirements reduced available capacity by 2.3 GW.
"Our region enters this winter season with sufficient capacity to meet forecasted demand, but reliability is never something we take for granted," added Aliff. "Tighter reserve margins, steep evening ramp periods and the potential for large winter storms can create challenging operating conditions. That is why MISO and our member utilities continue to focus on preparedness, coordination and operational readiness to ensure we can respond effectively when extreme weather occurs."
According to the National Oceanic and Atmospheric Administration (NOAA), above-normal temperatures are expected across much of the MISO footprint this winter, while temperatures in the South Region are forecast to be closer to seasonal norms. NOAA also projects above-normal precipitation in the South Region and below-normal precipitation across portions of the Great Lakes.
MISO and its member utilities continue to strengthen operational readiness through seasonal assessments, winter preparedness drills and other training exercises. These activities help operators sharpen decision-making skills and enhance communication and coordination during complex reliability events, it noted.
MISO will present its winter readiness assessment during a stakeholder workshop on Wednesday, Oct. 28 at 2 p.m. ET. To register and access presentation materials, visit the MISO website.
