How Wednesday's historic Maryland tornado outbreak happened

The event emerges as one of the most significant tornado outbreaks in the state in years.

Although multiple rotating thunderstorms — or supercells — produced twisters across many locations in Maryland, the one that swept across Montgomery, Howard and Baltimore counties was a particularly prolific tornado producer.

That supercell produced tornadoes near Darnestown, Poolesville, Gaithersburg, Olney, Columbia and Baltimore. Eyewitness footage showed that some of these twisters were quite large and more typical of what’s common in the Plains and southern United States. Drone video even revealed a multivortex tornado at times, meaning the twister had multiple swirls that orbited around the central funnel.

The National Weather Service received 16 tornado reports from Maryland, one from Loudoun County and four from eastern West Virginia.

It is not clear how many tornadoes occurred or how strong they were; meteorologists at the National Weather Service will survey damage beginning Thursday to determine this.

But the swarm of twisters came somewhat as surprise. Although the Weather Service forecast office serving the Washington region had mentioned that “a tornado or two” was possible in its Wednesday morning discussion, the agency’s Storm Prediction Center based in Norman, Okla., never issued a severe thunderstorm or tornado watch. It only placed the area in a Level 1 out 5 “marginal risk” zone for severe storms, while highlighting a low risk of twisters.

The Capital Weather Gang mentioned the slight possibility of tornadoes on social media Wednesday morning as well as in its early afternoon forecast update, but no forecaster we know of anticipated one of the most prolific tornado outbreaks in recent memory.'>>>

https://www.washingtonpost.com/weather/2024/06/06/maryland-tornadoes-montgomery-gaithersburg-explained/?