GroundTruth

- GroundTruth
  
  For more than 20 years Earth Networks has operated the world’s largest and most comprehensive weather observation, lightning detection, and climate networks.
  
  We are now leveraging our big data smarts to deliver on the promise of IoT. By integrating our hyper-local weather data with Smart Home connected devices we are delievering predictive energy efficiency insight to homeowners and Utility companies.
- GroundTruth
- WeatherBug
  - Consumer
  - Corporate
- WeatherBug
  - Consumer
  - Corporate

Late April to mid-July is usually a busy couple of months with severe weather in “Hail Alley,” which historically consists of Nebraska, Colorado and Wyoming. These three states see the most frequent hailstorms each year and typically the largest hailstones. On this day 22 years ago, another part of the U.S. accustomed to severe weather, but not major hailstorms got a rude awakening from Mother Nature.

A warm front had pushed north of the Mid-Atlantic on April 22, 1999, but an unusually strong cold front followed the next day. Low pressure over Indiana charged east along the front and slammed into unstable air across the Mid-Atlantic and produced a dangerous hail-producing thunderstorm in southwestern Pennsylvania around midday. The storm expanded in size and blew across West Virginia, Maryland and Virginia within six hours.

The hail reports were extraordinary for the Mid-Atlantic. An area accustomed to pea and penny sized hail in severe thunderstorms was pelted with hailstones as large as big apples in Winchester, Va. This particular portion of the northern Shenandoah Valley was hit hardest with $3 million in property damages alone. Baseball sized hail was reported in Capon Bridge, W.Va., with hen egg sized hail blasting Waynesburg and Marion, Pa.

The hailstorm did not produce any known damage in southwest Pennsylvania or Maryland, but West Virginia and Virginia were hit hard. Car windshields were smashed, car frames were dented, homeowners had to pick up glass in their yard following the storm and the hail shredded small bushes and plants.

The storm caused $119 million in property damage by today’s currency standards in its six-hour streak across the Mid-Atlantic! No other hailstorms in the Mid-Atlantic’s history have caused more damage than the severe thunderstorm that began in southwestern Pennsylvania and swept to southeast Virginia on April 23, 1999.

While the southern Plains and South have seen their fair share of severe weather so far this year, the Mid-Atlantic’s best chance for widespread severe thunderstorms is typically now until mid-June. Although severe weather does occur through the summer, dangerous thunderstorms become more scattered in nature. Be sure to have an emergency plan for when dangerous thunderstorms threaten your area.
---
Story Image: A thunderstorm with a hail shaft is shown. (Courtesy of Wikimedia Commons)

- Live Radar
- - Weather Details
- Forecast
  
  }
- Featured Videos
- Air Quality

On This Day in 1999: Hailstorm Crushes Mid-Atlantic