California and the Desert Southwest have been getting hit with some short sprint heat events as of late where the peak demand within CAISO has been forecasted above the 36.0 GW mark only to quickly drop back down into mid-20 GW level.

Figure 1 | CAISO Peak Power Demand – Actual and Forecast for end of May/early June 2025

The chart above illustrates the latest weather driven peak power demand uptick within CAISO (left) where the blue vertical bars represent the forecasted number while the black line with orange dots indicate where the actual volume ended up settling in at.  The charts to the right break down the aggregated power demand by the three key balancing regions within CAISO with Pacific Gas and Electric (PGE) at the top while SoCal Edison (SCE) is represented in the middle frame and San Diego Gas and Electric (SDGE) is on display in the bottom frame.  One thing to point out with the latest above normal weather sprint is SCE’s peak demand realized higher than the forecast given the simple fact that the warmer temperatures seeped into the coastal demand sub-areas, which in turn boosted the overall consumption of electricity.  SDGE’s forecast faltered a bit as the heat did not penetrate such demand areas while PGE tracked its forecasted values during the heat event.