Burst of exceptional heat in Northeast to linger through midweek

A noticeable warmup is expanding across the Northeastern states through midweek, AccuWeather meteorologists say. This burst of early September heat may be welcomed by vacationers flocking to the lakes and beaches, but could feel downright hot for residents taking part in other outdoor activities.

A shift in the upper-level pattern will be responsible for the climbing temperatures intruding across the Northeast early this week and is expected to linger through Thursday.

"A large high pressure area over the Southeast is pumping heat and humidity into the Northeast," explained AccuWeather Senior Meteorologist Heather Zehr.

As temperatures soar into the 90s and even crest the 100-degree Fahrenheit mark, some locations will observe higher temperatures than what has occurred throughout the entire summer. Philadelphia for example reached 96 degrees on Monday, a daily high temperature record, and is on track to reach into the upper 90s into midweek, continuing to challenge daily temperature records through Wednesday.

Throughout the last few months, the City of Brotherly Love reached its peak summer temperature of 95 degrees on both June 2 and July 13. Although meteorological summer has come to completion, Philadelphia surpassed that mark on Monday, reaching an astounding 96 degrees. The city might not be finished either as it is forecast to reach or surpass 96 numerous times this week as the heat wave sets in across the region.

To put into perspective of how noticeably hot these conditions will be in areas of the Northeast for early meteorological fall, forecasters outline how temperatures expected for this week compare to typical values this time of year.

"Temperatures early this week are topping out 10-15 degrees above normal from interior New England down through the mid-Atlantic, while coastal areas in New England will be closer to the historical average. Even those areas will warm up heading toward the middle of the week," said Zehr.

It has been several years since some cities across the Northeast, including Columbus, Ohio, reached the 90-degree mark during the first week of September. Back in 2018, numerous temperature records were set across the Northeast and Ohio Valley, and, at the time, September 2018 claimed its spot as the third warmest September in the northeastern U.S. since 1895. Even individual states such as Delaware, Maryland and West Virginia set records in 2018 as the warmest September in recorded history.

Pittsburgh's streak of not reaching 90 degrees in September dates back to 2019. On Monday and Tuesday however, the city reached 91, and it is forecast to reach the lower 90s again on Wednesday.

The Nation's Capital can be one of the spots that climbs to 100 F this week, a value not yet reached this year. On Wednesday, residents may see the best chances for reaching or even surpassing the 100-degree mark as the heat continues to endure across the mid-Atlantic states.

Spots in northern and western Virginia, western Maryland and south-central Pennsylvania have observed rainfall amounts well below the historical average for the last half of the summer.


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Locations in Virginia such as Winchester and Staunton collected only 21% and 10% of their typical monthly rainfall for August, respectively, putting them both at either abnormally dry levels or even into the moderate drought category, according to the U.S. Drought Monitor.

From June 1 to Aug. 31, observations from Winchester showed that they only received 4.39 inches of rain, which is roughly 38% of what they typically do during the summer months.

AccuWeather meteorologists warn that dry conditions and soil can provide a setting that allows for the air above the surface to heat up more readily, leading to more intense heat than locations that have observed ample rainfall. As a result, the highest temperatures across the mid-Atlantic this week from the heat wave are likely to hone in on a corridor from Virginia to southern Pennsylvania.

By Thursday, most cities across the interior Northeast and mid-Atlantic region will feel a touch of relief from the early September heat wave as thunderstorms move into the area. Several locations are expected to have maximum temperatures drop anywhere from 4-8 degrees from Wednesday to Thursday.

By Friday, high temperatures in the 70s can return to New York, northern and western Pennsylvania and central Ohio. Residents across Virginia, and even in Washington, D.C., can see temperatures dip from the upper 90s and 100-degree mark early week to the 80s by the weekend.

Not only will the temperature difference be notable, but a shift to lower dew points this weekend will help to bring more comfortable conditions in general.

However, a storm set to track across the northern tier of the country early this week will approach the eastern U.S. by midweek, bringing damp weather in the form of showers and thunderstorms to the Northeast. These storms will have the potential to impact outdoor plans later this week as they slowly shift across the region.

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