Delaware Governor Matt Mayer issued a drought watch across the entire state.
He says Delaware has seen a steep and steady decline in precipitation levels for the second time in three years.
This comes as another heat wave is expected to hit the Philadelphia region this week, with temps reaching 90 degrees for the first time this June.
Residents are being asked to voluntarily reduce their outdoor use of water and practice "wise water use" in their homes. This includes limiting watering of lawns and outdoor plants, as well as minimizing watering with drinkable water.
An open burning ban is in place through September 30.