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Sterling Disaster Survey Report

October 5th, 1995, Mini - Tornado Outbreak

by Barry S. Goldsmith

Meteorologist, National Weather Service Forecast Office

Sterling, VA

On the evening of October 5th, 1995, a series of tornadoes struck east-central Maryland as the remnants of Hurricane Opal moved through the Mid-Atlantic region. At least three separate tornadoes were spawned by a powerful rotating thunderstorm between 8:30 and 9:45 PM EDT; a fourth, thus far unconfirmed, may have touched down in northeastern Maryland between 10:15 and 10:45 PM EDT. Other weaker rotating thunderstorms along the line spawned two additional twisters - in Leonardtown (St Mary's County) and Arnold (Anne Arundel County). All storms were moving at speeds of 40 to 50 mph.

1. Charles County - Between Ironside and Grayton

Time: 8:35 to 8:37 PM

Intensity: Weak F1 (70 to 95 mph)

Path length: 1.5 miles

Path width: 100 yards

Warning in effect: Tornado warning, issued at 8:25 PM

Lead time: 10 to 12 minutes

Preliminary damage estimate: $25,000 to property

2. Prince George's County - Camp Springs

Time: 8:59 to 9:03 PM

Intensity: Strong F2 (150 mph)

Path length: 2.5 miles

Path width: 200 yards

Warning in effect: Tornado warning, issued at 8:53 PM

Lead time: 6 to 10 minutes

Preliminary damage estimate: $5 million to property

3. Anne Arundel County - Odenton - Glen Burnie

Time: 9:31 to 9:39 PM

Intensity: Strong F1 (110 mph)

Path length: 6 miles

Path width: 100 yard average; up to 200 yards at some locations

Warning in effect: Tornado warning, issued at 9:27 PM

Lead time: 4 to 12 minutes

Preliminary damage estimate: $250,000 to property

Resident assessment of NWS warnings

Charles County...

Only one person experienced the tornado and she had just arrived home and had loaded groceries into her house. She did not have the opportunity to hear the warning.

Prince Georges County...

While some were caught by surprise, others were home watching television and caught the warning just before the tornado hit. The Prince Georges County director of the Office of Emergency Preparedness said he saw the warning on television and immediately called into the communications center and to start the response and rescue efforts before the confirmation calls even began to come into 911. He said the warning allowed them to be on the scene in just minutes, rescuing people trapped in their homes. There were several injuries but only three had to be sent to the hospital and none were serious.

Anne Arundel County...

Residents indicated they were aware of a tornado moving their way. Even those who were watching movies or non-EBS activated television were alerted by friends or relatives to the possibility of a tornado moving "from Bowie to the Odenton-Severn-Glen Burnie" area. In general, the residents in the Quarterfield Farms subdivision had just enough time to take protective action; residents in Odenton received the warning (from television crawls) as the storm struck.

Interviews with residents also showed how important within-county locations are in the text of a tornado warning. The impression they left me with was "the warning said SEVERN...that's US!!" Residents may have been less inclined to take action had only the county been used as a location identifier. The NWS office in Sterling is currently testing software which will facilitate the inclusion of city/town locations for severe thunderstorm or tornado warnings.

The only element of surprise expressed to me was how fast the tornado arrived after the warning was general, one to five minutes after it was EBS-activated. Most residents saw the crawl between 9:29 and 9:31 PM ("just as Seinfeld ended, as one resident put it).

The fact is, radar indicated that the storm had weakened over central Prince George's County, and re-intensified just before crossing the Patuxent River. This is borne out by the fact that there no damage reports have been received from densely populated Bowie, where the parent thunderstorm moved through less than 10 minutes before striking Odenton.