Hours issued for Pennsylvania, New York, New Jersey, Virginia, Maryland, and more
Atmospheric components combine to create a climate condition in which severe storms are likely to thrive across much of the Northeast and Mid-Atlantic; As a result, the National Weather Service’s Storm Prediction Center (SPC) issued severe thunderstorm watches for southern Vermont, New Hampshire, Vermont, New York including the entire New York City metro area, all of New Jersey, Delaware, Rhode Island, Massachusetts including the Boston metro area, and eastern Maryland and Pennsylvania including metro areas of Philadelphia and Baltimore, much of Virginia and all of Washington, D.C., and parts of North Carolina, Tennessee, and Kentucky.
Widespread severe thunderstorms with damaging winds are possible over southern New England into the mid-Atlantic and Missouri during this evening. Significant hail and strong gusts of wind are also possible this evening and into tonight across the central and northern high plains. The SPC also says there is an elevated tornado risk in parts of the Northeast. Right now, they say, the greatest potential for tornadoes is over New Jersey, Connecticut, Rhode Island, Delaware, eastern Maryland, Pennsylvania, southeastern New York, and most of Massachusetts.
According to the SPC, a convection-enhanced mid-level low and belt of strong mid-level airflow will continue eastward today over Pennsylvania and New York as a weak surface hurricane associated with it is also developing east. Surface heating in cloud breaks this afternoon is helping to destabilize the atmosphere, setting the stage for severe weather. Scattered thunderclouds are expected to form this afternoon along the surface/front winds and over areas of differential heating and spread eastward until this evening. The SPC says the data indicates damaging winds will be the main threat with a mix of multi-cell clusters and some supercells this afternoon and into this evening.
Additional storm bands and groups are expected this afternoon from eastern Kentucky and Tennessee to western Virginia along a spreading flow/front. This area would lie along the southern edge of high westerly winds, but thermodynamic features would favor occasional gusts with wind damage.
Within a severe thunderstorm watch area, local offices of the National Weather Service will issue severe thunderstorm warnings and tornado warnings for select counties when the threat materializes. Even before these warnings are issued, the National Weather Service urges people to know what to do and where to go when issued. They also want people to be sure that they have a way to obtain, listen to, and act upon any warnings that may be issued for their area.
The threat of severe storms and hurricanes will diminish later this evening, giving the Northeast and Mid-Atlantic the chance to enjoy calm, dry weather tomorrow.