The National Weather Service has a neat postmortem on the April storm that generated a record-setting 19 tornadoes in the D.C. region.
- Damage in St. Mary's County sustained during the 2011 Mid-Atlantic tornado outbreak. (National Weather Service, Sterling, Va.)
The local office of the National Weather Service has released its summer newsletter, the Sterling Reporter. Can't fault its lateness what with Irene and Lee unloading an ocean of rain over the D.C. region; would you rather read about the heat index or an approaching hurricane? Anyway, the publication has an interesting little postmortem on the historic tornado outbreak that unleashed heck in the Mid-Atlantic in April, 2011.
As you may recall, the outbreak began late in the evening of April 27 and was still throwing out twisters and car-hood-denting hail by late morning the next day. (Photo gallery.) The storm system responsible for this havoc created a total of 19 tornadoes in Virginia and Maryland, the "most tornadoes ever recorded for a two day period in April," says the D.C. NWS. The weather office put 38 tornado warnings on the wire during the outbreak, an epic slew that is beaten only by the 43 warnings issued during Tropical Storm Ivan on Sept. 17, 2004.
Thirteen of April's tornadoes were of the weakest EF-0 variety, weak being pretty fearsome when you're in the middle of it. Five that broke into EF-1 strength damaged houses and plucked trees from the ground. And one ferocious EF-2 left a track measuring 33 miles late at night in the Shenandoah Valley, the longest twister ever recorded in the Mid-Atlantic. Here is how the NWS characterizes that beastly spinner:
With peak winds estimated at 130 mph and a width of 400 yards, this EF-2 tornado was on the ground for over 20 minutes from its initial touchdown near Fulks Run, VA before it dissipated over St. Luke, VA. Damage included destruction of a mobile home, a poultry facility (see photo previous page), and numerous sheds in a swath from Orkney Springs to Basye to Bryce Resort. In addition, numerous roofs were taken off and hundreds of trees uprooted.
Two people were injured during that twister's time on earth. For more on the outbreak, consult the Sterling Reporter starting on page five. A list of all 19 tornadoes by location, time and intensity follows the jump.