Chicago has a true four-season continental climate: cold, often brutal winters and warm, humid summers. Both ends of the year drive power demand. Below: live conditions, the 7-day outlook, and what it means for electricity demand on the MISO grid.
Loading live weather for Chicago…
High and low temperatures, with the implied heating and cooling demand below.
Chicago is one of the clearest dual-peak grids. Deep winter cold pushes heating load (and electric heating where it is used), while humid summer heat drives air conditioning across the MISO North footprint. A polar vortex and a July heat wave stress the same grid for opposite reasons, so both heating and cooling degree days matter here.
MISO's system peak is in summer, but Chicago winters bring their own sustained high demand. Track heating degree days in winter and cooling degree days in summer.
See live MISO grid data →They measure how far the day's average temperature sits from a comfortable 65°F. Cooling degree days (CDD) count degrees above 65 and track air-conditioning demand; heating degree days (HDD) count degrees below 65 and track heating demand. More degree days means more energy used to keep buildings comfortable, and a higher grid load.
Temperature is the single biggest short-term driver of electricity demand. Hot afternoons and cold mornings push load toward the grid's limits, which is when prices rise and reliability is tested. Watching the forecast is watching the grid's next few days.
Live weather and the 7-day forecast come from Open-Meteo. Degree days are computed from the forecast highs and lows against a 65°F base. Live grid data is on the MISO region page.