By Renee Duff, AccuWeather meteorologist
August 22,2017, 7:38:19PM,EDT
Severe thunderstorms will march eastward across the northeastern United States, threatening to trigger damage and delays into Tuesday night.An unusually strong push of dry, Canadian air will clash with high heat and humidity in the southern and eastern U.S.
Thunderstorms will congregate and gain strength along this dividing line stretching from Montreal, Canada, to Nashville, Tennessee.
Blinding downpours and winds strong enough to knock down trees and power lines and toss around loose items will be the most far-reaching impact. Hail can also occur.
“A few of the strongest storms could even spin up a tornado,” AccuWeather Meteorologist Eric Leister said.
The thunderstorms will tend to move fast enough to limit the flash flood threat to localized areas. Excess water on roads and quick rises on small streams will be more common.
Stretches of interstates 64 70, 80, 81 87 and 90, may be slowed during busy commute times as downpours reduce visibility to near zero.
Those headed to Little League World Series games in Williamsport, Pennsylvania, can expect thunderstorms and delays. At the first rumble of thunder, fans should head to their vehicles, since the venue offers little shelter from storms.
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After sunset, the storms will begin to transition to more of a heavy rain setup.
"It is possible some communities near and north and west of New York City, Philadelphia, Baltimore and Washington, D.C., are hit hard with urban flooding and locally strong winds Tuesday night," according to AccuWeather Chief Meteorologist Elliot Abrams.
Some of the downpours could linger into the Wednesday morning commute in the I-95 corridor throughout the Northeast.
Farther southwest along the tail end of the system, thunderstorms could turn feisty with torrential downpours, frequent lightning and gusty winds from central Arkansas westward through the Red River on Tuesday evening and overnight.
As cooler air settles into the Northeast for the remainder of the week, the threat for heavy and locally severe thunderstorms will sink southward toward southeastern Virginia and the Carolinas on Wednesday.