Mostly cloudy skies with highs in the mid-70s are forecast in the Baltimore area Thursday, according to the National Weather Service.

Fog and drizzle are possible in the morning hours, with humidity expected to be increasing. Early morning lows were expected in the upper 50s.

Patchy fog could move back in Thursday night into Friday morning, with lows around 60 degrees. Humidity is forecast to continue to build Friday as a frontal system approaches.

Highs are forecast to reach the upper 70s Friday until the frontal system moves through, bringing rain and thunderstorms and cooling temperatures significantly. Storms are not expected to be severe but could bring more than an inch of rain.

Temperatures could drop to the lower 50s Friday night, with highs around 60 and lows in the 40s for the weekend.