First Frost Advisory Forecast For Maryland With Brief Cold Snap: NWS

MARYLAND — The first frost advisory of the season is in effect for parts of Maryland overnight Monday and into Tuesday morning, with outdoor plants at risk of dying if left uncovered, according to the National Weather Service.

Temperatures as low as 33 degrees overnight will result in frost formation. The frost advisory, the first of the season, is in effect from 2 a.m. to 10 a.m. on Tuesday.

“Frost could kill sensitive outdoor vegetation if left uncovered,” the NWS said. “Take steps now to protect tender plants from the cold.”

The frost advisory is in effect for these areas of Maryland: Washington, Frederick, Carroll, Baltimore, Cecil, Prince George’s, Anne Arundel, Charles, Allegany, Montgomery, Howard and Harford counties, as well as the city of Baltimore.

"Frost advisories and freeze warnings have been issued across a large chunk of the forecast tonight into Tuesday morning," the NWS said. "Low temps look to all between 31-37 degrees in most locations with sheltered valley locations falling into the 20s."

The first frost of the season is coming slightly earlier than usual. Nov. 15 is the average date of the first frost in central Maryland, according to The Old Farmer’s Almanac. In a light freeze of 29 to 32 degrees Fahrenheit, tender plants are killed. A moderate freeze, which occurs when temperatures dip to 25 to 28 degrees, causes more damage, according to The Old Farmer’s Almanac.

The average date of the first frost is an estimate based on historical climate data from the National Oceanic and Atmospheric Administration’s National Centers for Environmental Information. The probability of a frost occurring before the first frost date is around 30 percent.

"The threat of a frost and freeze will expand to cover more of the Northeast, with perhaps only the urban areas along the I-95 corridor avoiding such conditions from Monday night to Tuesday morning. Many areas are likely to experience their lowest temperatures of the season so far," meteorologists at AccuWeather said.

The best way to protect plants from frost is to cover them with a blanket, bedsheet or some type of row cover. Drape them loosely over the plants, and anchor with them bricks or rocks.

After the overnight frost advisory, the rest of the week is expected to be unseasonably warm, with temperatures possibly reaching 80 degrees on Friday and Saturday.

Here is a look at the National Weather Service forecast for this week in central Maryland:

Monday: Sunny, with a high near 62.

Monday night: Patchy frost after 4 a.m. Otherwise, mostly clear, with a low around 34.

Tuesday: Patchy frost before 9 a.m. Otherwise, sunny, with a high near 67.

Tuesday night: Mostly clear, with a low around 44.

Wednesday: Partly cloudy, with a low around 49.

Wednesday night: Mostly clear, with a low around 42.

Thursday: Mostly sunny, with a high near 76.

Thursday night: Mostly cloudy, with a low around 55.

Friday: Mostly sunny, with a high near 78.