Most widespread severe weather predicted in Northeast since last summer

AccuWeather meteorologists are warning residents of the northeastern United States that a severe weather danger is expected into Wednesday night. It could become the most widespread eruption of severe storms the region has experienced since August 2020.

Even though a great number of severe weather incidents are not anticipated, the severe weather risk spans 14 states from the Ohio Valley to coastal areas of the mid-Atlantic and New England and even includes parts of southeastern Ontario and southern Quebec. By 4 p.m. EDT on Wednesday, most of the Northeast was under a severe thunderstorm watch.

The key ingredients for severe weather in the Northeast into Wednesday night will be surging temperatures in the 80s and 90s as well as a big boost in humidity levels.

The map above shows the Storm Prediction Center outlook for severe weather Wednesday and Wednesday night.

The air Wednesday afternoon into the evening has been more humid than it has been since last fall or last summer in some cases, according to AccuWeather Meteorologist Matt Benz. That could add fuel to the development of big thunderstorms.

"An approaching cold front from the northwest will provide the necessary lift in the atmosphere for thunderstorms to develop and grow tall," Benz explained.

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The main threats to motorists will be from sudden poor visibility from downpours and shifting winds. Those spending time outdoors during the afternoon and evening hours should be on the lookout for rapidly changing weather conditions that may lead to lightning strikes. AccuWeather forecasters say that if you can hear thunder you are at risk for being struck by lightning.

As storms approach major and regional airport hubs, expect airline delays.

"Some of the strongest storms have the potential to bring wind gusts between 60 and 80 mph," AccuWeather Senior Meteorologist Randy Adkins said. For comparison, a Category 1 hurricane has maximum sustained winds of 74 mph or greater.

Around noon on Wednesday, NOAA's Storm Prediction Center reported at least 3 people had been injured in Yates County, New York, after a lumber building under construction collapsed amid wind gusts of up to 57 mph.

There is the potential for tree and property damage from the storms as well as localized power outages. People are advised to bring trash cans and recycling bins in promptly as winds can be strong enough to send these loose objects airborne.

By early Wednesday night, around 140,000 electric customers across the Northeast were without power in the wake of the storms, AccuWeather Meteorologist Jesse Ferrell said.

A few incidents of damaging hail are possible. It may not be a bad idea, if possible, to park vehicles in a garage as opposed to on the street or in a driveway, AccuWeather forecasters recommend.

In a handful of the strongest storms, a brief tornado cannot be ruled out. The greatest risk for isolated tornadoes appears to be from near the northern border of Pennsylvania to upstate New York, western Massachusetts, northwestern Connecticut and much of Vermont.

Not every location will be hit by severe weather and a number of places may not even get thunder and lightning during the event. A few spots may even escape without a drop of rain into Wednesday night.

Since it may have been a while that some communities have last been hit with severe weather in the Northeast, let alone thunderstorms, AccuWeather meteorologists urge people to take severe weather threats seriously. When a severe thunderstorm or tornado watch is issued, it is time to pay close attention to the weather. When a severe thunderstorm or tornado warning is issued, it is time to take action and seek shelter immediately.

The most likely time for severe thunderstorms and isolated tornadoes Wednesday will be from 1-9 p.m. local time. With a few exceptions, the storms will hold off along the Interstate 95 corridor until the end of the afternoon or during the evening.

AccuWeather forecasters say that while the midweek outburst of severe storms is likely to stop short of an August 2020 outbreak, it could be the most widespread severe weather event since then. There were hundreds of damaging wind incidents from thunderstorms and a handful of tornadoes scattered through the Northeast states during the nine-day stretch back in Aug. 21-29, 2020. A few dozen cases of high winds could unfold with the storms on the doorstep.

There have been smaller pockets of severe weather that have affected a fraction of the Northeastern region so far this spring, but none perhaps as far-reaching as the looming event.

One of the more recent severe weather events occurred on May 3 and 4, 2021, when a cluster of wind and tornado reports came in from across portions of Pennsylvania and Maryland to Virginia and Delaware.

The most violent, recent severe weather outbreak north of Pennsylvania occurred back on Oct. 7, 2020, when there were 128 high wind reports that included a couple of tornadoes from upstate New York to the southeastern Massachusetts coast.

Strong winds associated with a derecho destroyed a billboard in Johnsville, New York, on Oct. 7, 2020. (Photo/NWS Storm Survey Team)

The October event was later classified as a derecho by the National Weather Service when a survey team found damage from high winds along a 320-mile-long swath. Gusts as high as 100 mph were observed. Derecho conditions are not anticipated with the severe storm threat into Wednesday night in the Northeast. However, a derecho is not needed to bring a threat to lives and property at the local level.

The heat and storms at midweek will be swept away as a cold front sweeps through during Wednesday night and early Thursday.

In the wake of the front, cool conditions for late May standards will settle over the region through the Memorial Day weekend. Rain is forecast to accompany the cool weather on multiple days, especially from the central Appalachians to the mid-Atlantic and southern New England coasts.

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