Shelf-Cloud Mania!
We got a several photos of Shelf Clouds on our AccuWeather.com Facebook page and Photo Gallery yesterday. Here they are along with companion radar shots. The first is from koconutz104 (who has many more photos of the event) in Stamford, Connecticut yesterday morning:
This same storm was sighted earlier in The Bronx, NY by Jose D...
And still earlier by Jackie A. in Bergen County, NJ...
This radar image below shows both of their approximate locations:
Out in the Midwest, this storm approached Quincy Illinois after 10 AM and was captured by an AccuWeather.com Forums user:
By the time approached Saint Louis, MO early in the afternoon, it had weakened on radar, but still had a shelf cloud per this picture by Forums user tstolze.:
Of course, as I've proven before, even dissipating storms can have beautiful shelf clouds.
But probably nothing tops this YouTube video, taken by Ben Holcomb on Thursday as a storm moved off of Lake Michigan towards Grand Haven (you can read his entire report on his website):
Shelf clouds are a type of Arcus Cloud and are not uncommon with summer thunderstorm complexes, especially MCC (Mesoscale Convective Complexes) like we saw yesterday in the Quincy shot. I'll let WikiPedia explain how they are formed: "Cool, sinking air from a storm cloud's downdraft spreads out across the surface with the leading edge called a gust front. This outflow undercuts warm air being drawn into the storm's updraft. As the cool air lifts the warm moist air, water condenses creating a cloud which often rolls with the different winds above and below."
