Cold weather is here, and while MISO’s winter outlook shows sufficient supply to meet demand this winter season, there are always potential risks and challenges associated with managing the electric grid under extreme weather conditions. In November, MISO held its annual Winter Readiness Workshop and discussed the region’s winter forecast, readiness for generation and transmission, and winterization survey results. Here a few highlights:  

Weather Forecast for MISO 

Our region covers parts of 15 states and the Canadian province of Manitoba — weather patterns can vary tremendously. MISO meteorologists create weather forecasts for each of MISO’s three regions: 

• • North Region: Near-normal temperatures. 
  • Central Region: Slightly warmer than usual with above-normal precipitation across the Great Lakes. 
  • South Region: Above-normal temperatures and drier than usual.  

The winter weather will be influenced by a weaker La Niña which opens the door for more cold blasts throughout winter. MISO will be monitoring the Polar Vortex, which can cause cold air outbreaks. There may be cold spells and heavy precipitation in the Midwest while the South could also experience colder weather than usual at times.  

Winter Energy Demand and Supply 

MISO expects winter demand could reach 107 GW with 122 GW of supply available under normal grid and generation outage conditions. The all-time winter record for power demand is 109 GW on Jan. 6, 2017.  

Natural gas is expected to be in good supply with storage levels higher than average while coal inventories will be slightly lower than last winter, but still above average. While MISO forecasts average wind and solar energy production this winter, cold weather patterns and systems can significantly affect the performance of renewable resources. Lessons learned from past events like the 2019 Polar Vortex and the 2020 wind drought have helped MISO improve how it manages renewable energy risks. 

Forecasting and Preparedness 

MISO’s Net Uncertainty Forecast helps predict how uncertain energy supply could be on a given day and adjusts reserve requirements accordingly. MISO has upgraded its forecasting tools, including a thermal generation risk dashboard and better tracking of fuel and pipeline issues. 

Coordination with Neighbors and Stakeholders 

MISO coordinates closely with neighboring energy systems like PJM and SPP throughout the winter, especially during cold spells. PJM expects above-normal temperatures, while SPP expects near-normal or slightly warmer temperatures. This collaborative approach allows MISO and our neighbors to better serve our collective customers. 

Also critical to winter readiness and operations is the coordination we undertake with our member utilities, states, and key stakeholders. MISO’s operations risk assessment (ORA) team works diligently throughout the year refining and implementing processes and technologies to gather, assess, and plan for various scenarios. This work helps us mange what can sometimes be unpredictable. If you think that sounds complicated, you are correct.