Weekly Weather Event -Week of April 19thApril 23, 2021
April 21st saw high winds and hail sweep through much of the East Coast. The Storm Prediction Center recorded 8 total hail reports and 73 wind reports sent in by storm spotters with some with wind speeds exceeding 60 mph. The storm also produced hail up to 1 inch in diameter throughout the highest risk areas, which at one point during the day encompassed the entire state of New Jersey. Behind this line of severe weather, temperatures dropped considerably, bringing freeze warnings in behind the strong winds and hail.
Thunderstorms are classified as severe when they meet one or more of the following criteria: wind gusts of at least 58 mph, hail at least one inch in diameter, and/or a tornado. Winds associated with severe storms are often called “straight-line” winds, as they are caused by winds that typically have a uniform direction. This is to contrast the rotational winds associated with tornadoes. Straight-line winds are typically generated by a thunderstorm’s downdraft, where colder air from within the storm cloud sinks to the ground and displaces the air beneath it. These downdraft generated winds can be quite strong, as seen by the storm on the 21st, causing damage to trees or blowing unsecured items away.