Weather Tidbits: Shelf Clouds

This edition of Weather Tidbits will be discussing shelf clouds. Shelf clouds are typically associated with squall lines, or a strong line of downpours or thunderstorms. With a shelf cloud passage, the strong winds will come first, followed by the rain behind it. You may see a shelf cloud approaching with a strong cold front. The structure of this cloud is caused by the distribution of air masses within the airflow. The updrafts of rising warmer, moist air can be seen in the leading outer part of the shelf cloud. The underside appears turbulent and wind-torn. This is where the colder, denser air sinks to the surface in the form of cooler, gusty winds with rain following behind it. The main severe damage from shelf clouds is from damaging winds, but a brief spin-up tornado is possible as well.