LOS ANGELES (AP) — California’s power grid operator may ask residents to voluntarily conserve electricity this week as record-breaking heat blankets the West.

The California Independent System Operator says it could issue “Flex Alerts” Wednesday and Thursday because torrid conditions engulfing the West have tightened energy supplies.

The potential Flex Alerts would be in effect during the hours from 4 p.m. to 9 p.m.

The summerlike heatwave arrived with spring still on the calendar as a dome of high pressure over the Four Corners region spread west.

Oven-like daytime highs have been followed by very warm nights. Palm Springs hit a record 120 degrees on Tuesday.