BALTIMORE, MD — The Baltimore-Washington area is under a tropical storm warning as Tropical Storm Isaias picks up steam in the Atlantic. Forecasters say extensive flood damage and limited wind damage are anticipated in Maryland, where much of the state was placed under a tropical storm warning Monday morning.

The warning means tropical storm-force winds are expected within 36 hours. Wind gusts may reach 70 mph in Annapolis and up to 60 mph in Baltimore, according to the National Weather Service, which is calling for about 40 mph sustained winds to blow through the region Tuesday morning through Tuesday afternoon.

Flash flooding is also a major concern, with 4 to 8 inches of rain or more expected to fall between Monday night and Tuesday evening in Maryland. Residents are advised to begin preparing for extensive flood damage and some wind damage now. The threat is high along and east of the Interstate 95 corridor. Significant impacts may also occur along and east of the I-81 corridor too.

Parking lots, streets, ditches, creeks and small streams could turn into dangerous rivers, according to the National Weather Service. Underpasses may be submerged. Roads and bridges may become impassable, weak or washed out.

Baltimore City is preparing for potential flooding near the Inner Harbor and other waterways from Monday into Tuesday and is offering sandbags from 9:30 a.m. to 4 p.m. Monday on Thames Street at Broadway. Residents have to fill their own sandbags and show proof of city residency. Annapolis is offering free sandbags at Truxton Park from 10 a.m. until 4 p.m. or whenever sand runs out.

In Howard County, officials say they are inspecting channels in the Ellicott City watershed and removing debris as necessary.

The storm was 620 miles south-southwest of Baltimore and 590 miles south-southwest of Washington, D.C., as of 11:40 a.m. Monday. Isiais was moving north at 13 mph with 70 mph winds.

Calvert, Caroline, Dorchester, St. Mary's and Wicomico counties are under a tropical storm warning, which calls for winds of 40 to 60 mph winds with gusts up to 75 mph Tuesday morning until Tuesday afternoon. There is a chance of tornadoes around Ocean City as well as in southern Maryland, according to the warning.

"Please don't let your guard down just because Isaias is no longer a hurricane," Russ Strickland, executive director for the Maryland Emergency Management Agency (MEMA), said in a statement.

"Be prepared for potential power outages, flash floods and tidal flooding," Strickland said. "This is still a dangerous system."

Marylanders should ensure to pack at least two face coverings for each person as well as hand sanitizer and disinfectants in their disaster supply kit, according to MEMA.

According to MEMA, central Maryland will be affected, and the lower Eastern Shore and southern Maryland will be the hardest hit. If the storm makes a slight shift west, it could bring heavy rain to parts of western Maryland, officials say, advising most Marylanders will likely feel some effects from Isaias.

"Major rainfall flooding may prompt many evacuations and rescues," according to the tropical storm warning for the Baltimore-Washington region.

Floodwaters may rush into structures, leaving them uninhabitable or gone altogether, the tropical storm warning states. Flood control systems and barriers could become overwhelmed, officials caution. Runoff in mountainous areas may lead to mudslides.

Anne ArundelBaltimore, Calvert, CarrollCecil, Charles, HarfordMontgomeryPrince George's and St. Mary's counties as well as Baltimore City and the District of Columbia are under a tropical storm warning.

Before the storm arrives, people in these areas should prepare, officials say.

Flash Flood Watch Starts Monday Night 

The National Weather Service issued a flash flood watch for parts of Maryland as the East Coast braces for Tropical Storm Isaias. Forecasters say the storm is "likely to result in significant flash flooding" around small streams and creeks in Maryland. Read more at Patch