Reporting Tim Williams
BALTIMORE (WJZ)– WJZ’s First Warning Weather Team has been studying our recent violent storm and reveals just how unusual and destructive it really was.
Tim Williams explains this wicked storm is called a derecho.
The vicious storm that raced through Baltimore brought howling winds, drenching rains, brilliant lightning and booming thunder.
It was no ordinary storm that swept across Maryland at 60 mph. It was a derecho.
WJZ‘s Bob Turk and meteorologists Bernadette Woods and Tim Williams reported on this weather phenomenon.
“A derecho is a long-lived line of thunderstorms producing damaging winds over 58 miles per hour. In this case it lasted a few states and it worked off heat that was over 100 degrees,” said Woods.
“It sounded like the whole house was coming down,” a woman said.
The strength of derechos is often compared to that of a tornado, but it’s their punishing straight-line winds that topple trees onto houses, cars and power lines.
“Damage from a derecho is different from what we would see in a tornado outbreak because in a tornado outbreak there would be concentrated areas, where in this case it covered everyone from the northern part of the state straight down through the southern counties,” explained Woods.
Our June 29 derecho actually formed that morning in the Midwest over Iowa. NASA satellite images of the storm show the storm as it traveled more than 700 miles. First Warning Weather tracked winds at more than 70 mph.
“That’s a category one hurricane. It had straight-line winds, so the kind of damage we saw over a huge area was even probably more extensive than a hurricane would even cause,” Turk said.
The storm was still packing a powerful punch when it reached the East Coast late that night. The 911 system was flooded by people frightened by the intensity of the storm.
Until this storm, many people had never heard of a derecho.
“In this part of the country we have interference from the ocean, interference from the mountains and that sort of breaks up these lines of storms, but in this case, it was stronger than even that,” said Woods.
These storms typically come with incredibly intense lightning. A satellite image obtained by WJZ captured almost 1,400 lightning strikes in 15 minutes.
As the derecho roared across the county, the National Weather Service issued nearly continuous warnings.
“The National Weather Service reported over 1,200 reports of severe damage in over 11 states, which is really unprecedented,” Turk said.
The last derecho to strike Maryland was in 2008.
Tuesday night at 11 p.m., Mary Bubala will talk to BGE’s president and CEO about how his company responded to the devastating power outages caused by the derecho.