With skies Monday morning that could look and smell smoky, the Maryland Department of the Environment has issued a Code Orange and Code Yellow air quality alert for Baltimore and surrounding counties due to the “uncontrolled” wildfires at the Aberdeen Proving Ground in Harford County.

Air quality alerts will last until at least noon, according to MDE.

Code Yellow means that the air quality poses a moderate risk to people sensitive to air pollution, according to MDE. Code Orange means the air quality is unhealthy for sensitive groups such as children and adults with respiratory and heart conditions.

Harford and Cecil counties, as well as the northern portion of Baltimore County, are under Code Orange. Baltimore City, Anne Arundel, Carroll and Frederick counties are under Code Yellow, along with northwestern portions of Montgomery and Howard counties.

With the help of the National Guard, fire and emergency services at Aberdeen Proving Ground battled several fires Sunday afternoon, according to a Facebook post from emergency services.

Aberdeen Proving Ground’s Office of Public Affairs did not immediately respond to a request for comment.

The fire started Thursday, a day before the Maryland Department of Natural Resources implemented a statewide burn ban. Dry and windy weather, along with foliage on the ground, creates conditions conducive to wildfires.

“The ban is in response to very dry conditions in recent months,” department spokesman AJ Metcalf said. “And it resulted in a lot of dry leaves on the ground. If an open fire goes sideways, it could be a wildfire.”

The Proving Ground fires spread to more than 100 acres, Chestertown Volunteer Fire Company said in a Facebook post. The post explained that the Proving Ground is a United States Army testing facility used to evaluate weaponry.

“By the very nature of these testing activities, fires are inevitable, especially in drought conditions such as we currently have,” the post said. “Due to the very large number of unexploded ‘live’ rounds, it is far too dangerous to put firefighting personnel on the ground. APG has a ‘Let it burn’ policy for range fires unless the situation gets out of hand.”

The fires created a plume of smoke that blew west toward Edgewood, White Marsh and Baltimore late Sunday, according to MDE. This caused some people to see and smell smoke until Monday morning, although it is expected to dissipate later in the day.

Last October was one of the driest on record for the Baltimore area, said National Weather Service meteorologist Austin Mansfield.

There’s a slight chance of rain around Baltimore on Wednesday and Thursday, he said, but temperatures will reach record highs around 80 degrees on Tuesday and Wednesday.