Rounds of thunderstorms with torrential rain and gusty winds will ride the rim of heat and roll across portions of the northeastern United States into this weekend.
The weather pattern will raise the risk of flooding and isolated damaging winds. At the very least, travel disruptions and sporadic power outages are likely.
Temperatures will climb well into the 90s F at times from the Ohio Valley to part of the mid-Atlantic for the balance of the week. Meanwhile, temperatures will peak in the middle 70s to the middle 80s across northern New York state and central and northern New England.
"A weather setup such as this has produced storms with flooding in the past," according to AccuWeather Chief Meteorologist Elliot Abrams.
A batch or train of thunderstorms was responsible for the Johnstown, Pennsylvania, flood of July 19-20, 1977. Close to a foot of rain fell in 24 hours over the mountains north of the city. A series of dams failed with sent a wall of water into the city. Dozens were killed and damage topped $100 million.
A similar setup mostly likely was the cause of the Smethport, Pennsylvania, record rainfall and flood of July 17, 1942. In just 12 hours, 34.30 inches of rain fell. The torrential rain caused catastrophic mudslides and flooding that took the lives of more than a dozen people.
While an outcome similar to that of either flood is unlikely, some communities may face flooding on a smaller scale. Those spending time at campgrounds near streams and rivers should exercise caution and keep up to date on weather bulletins as they are issued.
This could evolve into a life-threatening event.
"Exactly where the temperature contrast zone sets up each day will determine the main path of the storms and areas at greatest risk for damage and disruptions from flooding and strong winds," according to AccuWeather Senior Meteorologist Dave Dombek.
Multiple rounds of thunderstorms will roll southeastward from the northern Plains and the Great Lakes region, to the central Appalachians and then the mid-Atlantic coast on a daily basis beginning on Thursday.
Each batch of storms can be accompanied by multiple downpours and unleash torrential rainfall.
One group of storms is likely from later Thursday into early Friday.
A second batch of storms is likely from Friday night to Saturday. This batch has the greatest potential to bring significant flooding.
A third series is likely from later Saturday to Sunday. This batch is most likely to affect a broad area with perhaps less intense rainfall but isolated incidents of flash flooding.
Some communities in the core of one or more of the storms may receive upwards of 4 inches of rain.
Meanwhile, areas to the south that remain in the core of the heat may receive little or no rainfall during the entire time into the first part of weekend.
The risk of flooding and damaging winds will be lower, but not non-existent in New England. Some rain and embedded thunderstorms are likely to reach the region. The area will be farther removed from the heat to the southwest, so the atmosphere may not be as volatile.
Ahead of the main severe weather and flooding threat, very spotty storms can erupt in the afternoon and evening hours in coastal areas from southern New England through the mid-Atlantic on Wednesday.