At the same time, a number of images were passed around as tornadoes that were clearly not tornadoes. In that light, we thought it would be good to examine a few of the most common scary looking clouds that sometimes are mistakenly called tornadoes.
Funnel vs. tornado
To start, there is a very specific definition of a tornado.
The circulation must reach the ground. If not, and it’s rotating, it’s likely either a funnel cloud or a wall cloud (see below). Simply, a funnel cloud is a tornado that does not reach the ground. Often, you’ll see funnel clouds make it about halfway from the base to the ground, though it can extend much further or much less.
Sometimes it’s not always apparent if the circulation — if there is one — is reaching the ground as trees (see here) can block the view, or a condensation funnel may not be apparent even if there is noted circulation at the surface.
Example: A likely funnel cloud in Brambleton, Va from June 1. It’s not possible to tell if this touched the ground. The National Weather Service has not reported a tornado in this area.
Example of likely wall cloud with possible funnel forming from June 1 outbreak in Takoma, Washington, D.C.
This video from June 1 in Greenbelt reported as a funnel or tornado closely matches what a tail cloud and wall cloud look like together.
Shelf clouds / roll clouds
Many of the photos circulated during the June 1 event were likely scud clouds. Example from Elkridge, Maryland.
Rain or hail shafts