ARLINGTON, Va. − A sprawling atmospheric river thathammered the Southeast with up to a foot of rainwas sweeping through the Mid-Atlantic states Tuesday, driving multiple inches of rain and the threat of coastal flooding, forecasters said. A "flash flood emergency" was declared in portions of far western Maryland by mid-afternoon due to the heavy rain, which has neared 5 inches in some areas, the National Weather Service said. In southwestern Allegany County, Maryland, the weather service warned residents that "This is a PARTICULARLY DANGEROUS SITUATION. SEEK HIGHER GROUND NOW!" Evacuations are ongoing northeast of Barton, Maryland, and the water in Georges Creek is reaching residences and businesses in Westernport, Maryland, after the creek rose six feet in three hours. Evacuations from flooding also have been reported in Mineral County, West Virginia. Flood watches have been been issued across the Washington, D.C., area including suburban Virginia, western Maryland and parts of West Virginia, the weather service said. Total rainfall amounts of up to 3 inches are expected, and there could be up to 5 inches along the Blue Ridge Mountains. Parts of central North Carolina, still recovering from the furious rains fueled by the the remnants of Hurricane Helene in September, could see 5 inches through Wednesday, the National Weather Service warned. The risk of flash flooding will stretch all the way into Pennsylvania. "There will continue to be a risk of heavy rain and strong to severe thunderstorms over the next couple of days," the weather service office in Morehead City, North Carolina, posted on social media. "Please be sure to have multiple ways to receive warnings, and please avoid flooded roads." Major storm:Gulf Coast to Virginia could be swamped with buckets of rain this week Atmospheric rivers are long, narrow stretches of atmospherethat transport vast amounts of water vapor − like rivers in the sky. Atmospheric rivers can vary greatly in size and strength, but the weather service says the the average atmospheric river carries an amount of water vapor roughly equivalent to the average flow of water at the mouth of the Mississippi River. Exceptionally strong atmospheric rivers can transport up to 15 times that amount of water. This atmospheric river has been hovering over the Southeast for days, trapped by a strong high pressure system to the north. Although much of the Mid-Atlantic region has been experiencing moderate to severe drought conditions, rainfall rates could become "heavy enough to support a flash flood threat," wrote meteorologist Peter Mullinax in the National Weather Service's short-range forecast discussion. Mullinax added that there was a "dearth of flood watches" in parts of Virginia and North Carolina. The "deep fetch" of Atlantic moisture will reach to the Great Lakes and the Ohio and Tennessee valleys, prompting widespread storms, Mullinax said. Thunderstorms will be more isolated there Wednesday, while rains will advance into the Northeast through Wednesday. In North Carolina, the arts-and-tourism town of Asheville was devastated by Helene's rains eight months ago. Homes and businesses were destroyed, bridges and highways were washed out, and the water system was severely damaged. The area has slowly recovered, and the luxury Grand Bohemian Asheville Lodge, closed since Helene, reopened May 8 after a $20 million renovation. Now the National Weather Service has issued a hazardous weather outlook for the area, warning of heavy rainfall and potential flooding through Tuesday. Rainfall totals are expected to reach 2 inches in higher elevations east of Asheville, and some areas could potentially receive up to 3.5 inches. A heat wavecontinued to envelop the Midwest. Records tumbled in recent days: It reached a startling 100 degrees in Humboldt, Minnesota, and 99 degrees in Grand Forks, North Dakota. Near record or record highs were forecast in many areas for Tuesday, and high winds and dry conditions prompted red flag fire warnings in much of the region. In Kansas City, Missouri, the weather service said the warming trend continues, peaking midweek with highs approaching 90 degrees. Denver could see 86 degrees Tuesday. The storm moving into the Mid-Atlantic had earlier stalled over the Southeast over the weekend, overwhelming some cities with rain. In Georgia, almost 7 inches of rain fell in Savannah and over 3 inches in Augusta. Over 4 inches of rain fell on Columbia, South Carolina. Some rural areas of South Carolina, Georgia and the Florida Panhandle were deluged with up to a foot of rain in recent days,AccuWeatherreported. Some rivers in the Southeast are forecast to reach flood levels later this week. A flood watch was in effect for northern Virginia, Washington, D.C., and suburban Maryland, the weather service said. A coastal flood advisory has been issued across parts of New Jersey, Pennsylvania and Delaware with potential flooding and water surges in low-lying coastal areas. Coastal cities along the Atlantic such as Miami and Charleston, South Carolina, already prone to high-tide flooding, could face increased flood risk if heavy rain adds pressure to already taxed drainage systems, AccuWeather said. Contributing: Iris Seaton and Will Hofmann, Asheville Citizen Times;Dinah Voyles Pulver, USA TODAY This article originally appeared on USA TODAY:Flash flood 'emergency': Atmospheric river hits Southeast, Mid-Atlantic
