 The city is opening seven recreation centers as cooling centers today only, in addition to the 14 cooling centers that will be open through Wednesday of this week. An excessive heat warning will be in effect from 11 a.m. until 8 p.m. this evening for the I-95 corridor, southern Maryland, and parts of the eastern shore in Washington County. The rest of the state will be under a heat advisory. Well, in the heat, there are a few things that you can certainly do to reduce the strain on the electrical grid and save some money on your electric bill.