10th anniversary of the 2012 derecho

[ACwx]

The bulk of this storm went south of the Philly region so many members of this forum probably missed out, but for anyone who was in South Jersey that night, it was the worst thunderstorm in decades. I can't find the article now but there was an account of a retired met from NWS Mount Holly, Jim Eberwine, who surveyed the damage near Buena and estimated the winds around there to be at least 100mph...the highest official gust was 87mph at ACY but notice there's a gap in station data just west of there so that's where I'd guess the strongest winds truly occurred.

The house I was living in at the time had a lot of trees directly around it, so I remember putting on headphones in order to avoid getting jump-scared in case lightning struck one of them. What I remember is the lightning...just...wouldn't...stop. It had to go on for over an hour and it was as vivid as anything I've ever seen. I also remember driving across the Somers Point bridge an hour before (since I worked at Gillian's in OC that summer) and remember very easily being able to see a shelf cloud across the sky even though it was nearly midnight. Can't even imagine how nasty it would have looked if there was more daylight to view it.

NWS did a nice comprehensive summary on the storm here, which also links to individual offices' summaries: June 29, 2012 Derecho (arcgis.com)

[snowlurker]

It hit Middletown, DE and took down lots of trees.

[Rainshadow]

We had to back up Sterling for most of the weekend (I think this happened on a Friday night) as they lost power.

It was surreal the PGA Tour was at Congressional and no spectators were allowed because of concern of falling limbs/trees.  Pre-Covid it sounded weird to hear no sound. 

[Rainshadow]

A well-organized cluster of thunderstorms with a history of producing widespread damaging winds advanced into a hot, unstable airmass over the Mid Atlantic. This derecho produced widespread, significant wind damage from southern New Jersey southward into the Delmarva during the late evening and overnight of the 29th. Salem, Cumberland and Atlantic Counties were hit the hardest. The counties were battered by the derecho which downed trees, power lines and poles, sparked fires and destroyed some homes.
There were three storm related deaths, two boys camping in Salem County and a man whose boat capsized in Absecon Bay in Atlantic County. A preliminary damage assessment put the cost at around $20 million for the three counties. In all sixteen homes were destroyed, ninety-two suffered major damage, one hundred eighty-seven suffered minor damage and another one hundred and twelve were affected by the derecho. In addition, forty-one businesses suffered major damage and three hundred twenty-nine suffered minor damage. A state of emergency was declared in Atlantic County. Governor Chris Christie mobilized the National Guard to help provide fuel and water. President Barack Obama has issued a disaster declaration for parts of South Jersey in the wake of the derecho. The president ordered federal aid to supplement state and local recovery efforts in Atlantic, Cumberland and Salem counties. Federal funds will be available to state and local governments and certain nonprofit private organizations. Atlantic City Electric reported 206,000 of its customers lost power; 105,000 of the homes and businesses were in Atlantic County. On Sunday July 1st, 119,000 of its customers were still without power. The utility restored power to its last customers on July 11th. Meanwhile in Cumberland County, Vineland Electric expected its remaining 1,800 customers that lost power to have it restored during the week of July 9th.
Strong thunderstorm development began across the Midwest and Lower Great Lakes regions during the afternoon of the 29th, with storms initiating across northern Illinois, near Chicago. Strong mid-level winds and an unstable airmass contributed to rapid development as well-organized storms progressed from northern Illinois through Indiana and Ohio. This robust convection continued to track southeastward into an airmass that was even more unstable due to abundant daytime surface heating. Late afternoon temperatures had peaked mainly in the mid to upper 90s with high humidity throughout the Mid Atlantic states, and as the potent thunderstorm cluster progressed from the Great Lakes to the central Appalachians and into the Mid Atlantic by late evening, thunderstorm activity was reinvigorated.
A robust gust front outpaced the main thunderstorm line, producing strong wind gusts as it traveled from the eastern shore of Maryland into Delaware and southern New Jersey. Shortly thereafter, the potent thunderstorm line tracked through the region, with additional damaging wind gusts. One cell in particular around Baltimore, MD experienced rapid intensification and expansion as it raced eastward into northern Delaware and southern New Jersey. This massive cell produced extreme damage throughout Salem, Cumberland, and Atlantic Counties in New Jersey. Damage to trees, power lines, and buildings was also significant throughout Delaware and the eastern shore of Maryland. Thunderstorms also dropped hail in several locations, ranging from penny to golf-ball size. Destructive wind gusts, between 65 mph to nearly 90 mph, were measured as this derecho tracked from the Lower Great Lakes to the Mid Atlantic coast.

[SalemCountyNJ]

That was a scary unforgettable night. I'll never forget  the debris in the yard and all the surrounding neighbors yards the next morning.  I never had seen such a mess. 

[rramblings]

I love in NW New Jersey so was not affected. But I do remember this derecho. I had friends in the Vineland area who were affected with some damage to their business which was covered by insurance fortunately.

[colonel_kurtz]

On 7/1/2022 at 12:19 PM, Bananashadow said:

It was surreal the PGA Tour was at Congressional and no spectators were allowed because of concern of falling limbs/trees.  Pre-Covid it sounded weird to hear no sound. 

How they got that course playable the next day was absolutely amazing. It looked like a war zone.