MD Weather: Severe Thunderstorm, Flood Watches Issued

Updated at 2:20 p.m.

MARYLAND — Heavy rains and strong winds from thunderstorms could arrive in the Baltimore-DC region just in time for the evening commute. A severe thunderstorm watch until 10 p.m. has been added to the weather warnings for the afternoon.

The thunderstorm watch is in effect for the city of Baltimore, plus Allegany, Anne Arundel, Baltimore, Calvert, Carroll, Cecil, Charles, Frederick, Garrett, Harford, Howard, Montgomery, Prince George's, St. Marys and Washington counties, the National Weather Service said.

A flood watch for the Baltimore-Washington, D.C., are is in effect from 4 p.m. to midnight on Tuesday.

The scattered severe thunderstorms are expected to arrive after hot and more humid air moves into the area Tuesday morning and afternoon. With the storms, excessive rainfall may cause the flooding of rivers, creeks, streams and other low-lying and flood-prone locations, the NWS said.

Damaging wind gusts and large hail are also "primary threats," the NWS said, noting that an isolated tornado is possible.

The flash flood watch is in effect for portions of DC, Maryland and northern Virginia, including Anne Arundel, Howard, Montgomery, Baltimore, and Prince George's counties.

Cities under the watch include: Silver Spring, Bowie, Annapolis, Odenton, Bethesda, College Park, Reisterstown, Columbia, Severna Park, Greenbelt, Germantown, Rockville, Arnold, Suitland-Silver Hill, Gaithersburg, Severn, Baltimore, Clinton, Glen Burnie, Ellicott City, Cockeysville, and Laurel.

"Hot and humid weather is back and it's bringing a severe weather threat along with it," NBC4 meteorologist Chuck Bell said Tuesday morning. "Storms likely to impact the PM commute in Metro DC with damaging wind gusts and localized flash flooding possible in the areas that had the heaviest rain last Saturday."

In its forecast, The Washington Post's Capital Weather Gang said that after temperatures climb into the low 90s on Tuesday, scattered storms are likely. Some of the storms could be strong to severe, with damaging gusts.

"The timing of these storms could be critical for the evening drive, with a risk for slower-than-normal traffic from heavier rainfall," AccuWeather Senior Meteorologist Matt Rinde said Tuesday morning. Airports could also face flight delays and cancellations.

Here's the NWS forecast for Maryland for the next few days:

Tuesday: Scattered showers and thunderstorms, then showers likely and possibly a thunderstorm after 5pm. Some of the storms could produce small hail and gusty winds. Mostly sunny, with a high near 92. Heat index values as high as 100. Southwest wind 8 to 10 mph, with gusts as high as 18 mph. Chance of precipitation is 60%. New rainfall amounts between a quarter and half of an inch possible.

Tuesday Night: Showers and thunderstorms likely, mainly before midnight. Some of the storms could produce small hail, gusty winds, and heavy rain. Mostly cloudy, with a low around 71. Southwest wind around 6 mph becoming calm in the evening. Chance of precipitation is 60%. New rainfall amounts between a quarter and half of an inch possible.

Wednesday: Mostly sunny, with a high near 90. Calm wind becoming west around 6 mph in the afternoon.

Wednesday Night: Mostly cloudy, with a low around 71. Light and variable wind.

Thursday: Mostly sunny, with a high near 88. North wind 3 to 6 mph.

Thursday Night: Partly cloudy, with a low around 69.

Friday: A chance of showers after 2pm. Mostly sunny, with a high near 85. Chance of precipitation is 30%.