From a scenic overlook on George Washington Parkway, a lightning storm can be seen moving through the D.C. area May 18, in Arlington, Va. (Jahi Chikwendiu/The Washington Post)

I’ve never seen lightning like this before. — Everyone in D.C., Thursday night.

The truth is you probably have, but every time it happens it seems more amazing than the last. The kind of lightning we saw over the District and surrounding areas Thursday night — anvil crawlers — is particularly stunning.

Lightning is the result of an electrical charge imbalance. Hail and ice are moving around in the cloud — some upward and some downward. The exact physics on how lightning forms is unknown, but scientists generally agree that these solid particles collide and become charged.

Lightweight things, such as small ice crystals, get a negative charge, and because they are so light, they get pushed to the top by the rising air. Heavier things, such as graupel and hail, get a positive charge and also fall to the bottom of the storm (because they’re heavy!). It also happens that near the ground there are negative charges, which add another layer of electrical excitement.

That triple-decker sandwich of charge differential and lightning is Mother Nature cracking the whip.

Now on to the good stuff — there’s a couple dozen forms that lightning can take. We saw a lot of those Thursday night, but the lightning that forked through the underbelly of the storm was arguably the best.

Anvil crawlers are exactly what they sound like — lightning that crawls across the anvil of the storm. You can usually find it when a big storm starts to weaken, like Thursday night’s, and they’re easy to photograph because it travels so much slower than a lightning bolt.

The storm was west of the Beltway, so high-level winds blew the anvil toward the east and set up a pretty good view for people in the District.

Thanks to everyone who shared lightning photos with us!


The thunderstorm moves over Fairfax with anvil crawlers and a cloud-to-ground lightning strike. This photo was taken from Fairfax Towne Center. (Kevin Ambrose)

Fairfax, Va. (Kevin Ambrose)

Dulles Airport. (Tom Hamilton via Flickr)

Fairfax. (Jason Maturo)

From Crystal City, Va. (Tyler Reber via Facebook)