According to a press release from the City of Coffeyville.

Due to the Southwest Power Pool issue of the Energy Emergency Alert Level 3, the City of Coffeyville is making preparations to initiate rolling blackouts in support of stabilizing the bulk electric system, should a directive be received from the GRDA and SPP.

Rolling blackout could range from one to four hours. The City of Coffeyville will attempt to notify customers of pending rolling blackouts by phone notifications to listed account numbers. They ask that you do not notify the system operations of this outage unless it extends beyond two hours.