Areas in the East and South will be at risk for severe thunderstorms packing damaging winds, flooding rain and frequent lightning strikes into Tuesday.
Into Monday evening, the greatest risk of heavy to locally severe storms will stretch from the Tennessee Valley to part of the I-81 and I-95 corridors. Cities that can be impacted on Monday include Nashville; Roanoke, Virginia; Charleston, West Virginia; Washington, D.C.; Baltimore; Philadelphia; New York City; Hartford, Connecticut; Providence, Rhode Island, and Boston.
During Tuesday, the main threat of flash flooding and severe weather will dip into the Deep South but will continue in part of the I-95 corridor in the mid-Atlantic and part of New England. Some of the metro areas, from Washington, D.C., to New York City and Boston, could be hit by heavy, gusty storms for the second day in a row.
Tuesday could be the worst of the two days for storms around Columbia, South Carolina; Raleigh, North Carolina; Richmond, Virginia, and Boston.
The storms have the potential to cause major disruptions to outdoor activities and travel.
As the storms roll through the major metro area airports, the risk of wind shear can be significant enough to aircraft to result in a ground stop. The most likely time for airline delays will be during the afternoon and evening hours as storms reach peak intensity.
Wind gusts with a few individual storms can be strong enough to knock down trees, damage roofs and cause power outages.
Enough rain could fall to cause flooding of basements and small streams on a regional basis.
The storms will bring wind-swept downpours that will pose hazards for those traveling on the ground. At the height of the storms, water can flow across flood-prone stretches of roadways and settle in poor drainage areas. Visibility can suddenly drop to unsafe levels for driving at highway speeds.
As the storms develop and rapidly approach locations, they can produce lightning strikes with little notice. If you can hear thunder you are at risk for being struck by lightning. Seek shelter immediately as storms approach.
A small number of the storms can also bring damaging hail to a few communities, while a small fraction of the strongest storms can also produce a short-lived tornado.
During Wednesday, the risk of locally drenching and strong thunderstorms will continue at the beaches from New England to the mid-Atlantic and South.
As the storms continue along the Atlantic Seaboard and over parts of the South into the middle of the week, a push of unseasonably cool and less humid air will expand over the Midwest and into the Appalachians.
A modified version of this air will spill into the South and along the Atlantic Seaboard during the middle to latter part of the week.