Funnel cloud or not?June 3rd, 2013 at 11:10 am by Nick Bannin under Weather
Since the June 1st tornado and more recently since horrific devastation in Oklahoma…more and more of you are playing an active role in observing the weather around you and sending pictures or information into the 22News Team.Often your reports include pictures, video or descriptions of what you see. From time to time you might tell us you’ve spotted a funnel cloud, tornado or even sent us pictures like the ones here from the storms on June 2nd 2013.
You might assume that based on the upsidedown shape that these pictures are of funnel clouds, but don’t be so sure. In order for a cloud to be considered a “funnel cloud” you need a rotating condensation funnel that is in contact with the cumulus clouds above (known in a thunderstorm as a wall cloud). Rotation is key…if a cloud is not rotating (even though it is moving), it may be considered a “scud” cloud or just a low hanging appendage of the main cloud above. To be clear, it’s almost impossible to tell based on cloud pictures alone whether these were funnel clouds or not without seeing rotation.
Once you’ve determined that there is tight rotation in that cloud then you have to figure out if that cloud is a funnel cloud or a tornado.
A tornado is clear when you have a condensation funnel cloud that is in contact with the ground OR a rotating condensation funnel causing debris or dust to spin up on the ground below it. Even if you don’t see the cloud touching the ground in some cases…if there’s debris flying just below it then it’s a tornado.