A potent cold front will gradually track over the Ohio Valley and the northeastern United States throughout the day. As the boundary nears the East Coast by Saturday afternoon and evening, ingredients for severe weather will combine to spark disruptive thunderstorms.
"During the afternoon and evening hours, atmospheric instability along this front is expected to peak, resulting in the development of strong-to-severe thunderstorms centered over the I-95 corridor", explained AccuWeather Meteorologist Adam Sadvary.
A severe thunderstorm watch is in effect until 9 p.m. EDT from northeastern Pennsylvania through southern New York state and into southeastern New England, including Boston.
Outdoor plans may need to be altered near metro areas such as Washington, D.C., Philadelphia, New York City and Boston as thunderstorms threaten multiple modes of severe weather. Even regions along Interstate 81 in eastern Pennsylvania and western Virginia will be at risk for damaging wind gusts ranging from 50 to 60 mph.
"The primary threats from these storms will be damaging wind gusts and heavy downpours, which can lead to localized flash flooding; however, hail cannot be ruled out," stated Sadvary.
Forecasters remind readers to be mindful of the danger of lightning in nearby storms and take cover in a safe, enclosed shelter when lightning is present. Experts advise to never take shelter under an isolated tree. Additionally, anyone caught outdoors in a thunderstorm should avoid elevated areas and immediately exit bodies of water such as swimming pools, ponds and lakes.
With many travelers heading to their destinations ahead of Independence Day, significant travel delays can occur as strong-to-severe storms impact the region. Motorists traveling along portions of interstates 80, 81, 90 and 95 should stay vigilant and weather aware as storms fire across the Northeast.
"Given the increase in travel prior to Independence Day, as well as the high population of this threat area, it will be crucial for those with interests in this region to keep an eye on the forecast and to have a backup plan in case storms create issues," noted Sadvary.
Picnic-goers from Virginia to Massachusetts should also stay up to date on the latest forecast and prepare for the possibility of shifting plans indoors.
With the potential for heavier storms to develop around dusk, some firework displays may be delayed or canceled for some Northeast towns and cities closer to the coast.
Ample sunshine and dry weather will return to the mid-Atlantic states and New England on Sunday as the slow-moving front shifts away from the coast. Daytime highs in locations like Boston, New York City and Philadelphia are expected to range from the mid-80s to near 90 degrees Fahrenheit on Sunday as the holiday weekend celebrations continue.
On Monday, Independence Day, conditions will likely remain mainly dry across the Northeast. Forecasters say that northern New England residents will experience comfortable weather, with temperatures near 80 F. Locations across the interior Northeast are expected to reach daytime highs in the mid-80s F to low 90s F, just a degree or two above average for this time of year.
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