A mass of cold air is expected to swoop down from Canada early next week, sparking the potential for strong storms and plunging temperatures to unseasonable lows.
"The ingredients are there for strong to severe thunderstorms," said National Weather Service meteorologist Dan Hofmann.
Sunday and Monday will bring hot, muggy weather, with highs in the low to mid-90s, Hofmann said. Scattered showers and thunderstorms are possible Sunday afternoon and evening.
The mass of cool, dry air will sweep into the region some time between Monday afternoon and Tuesday evening, bringing high winds and the potential for intense storms, he said.
Baltimore's Office of Emergency Management warned residents Saturday to prepare for strong storms.
"Early reports say very severe weather is possible Monday & Tuesday. Check your emergency kits & prepare now. Keep an eye on weather reports," the department posted on Twitter.
The front will bring cool and pleasant weather-- markedly different from a typical Baltimore July.
Wednesday should have highs in the upper 70s and low humidity, Hofmann said.