This landspout was photographed on I-80 west of Rawlins this afternoon. (NWS-RIW)
(Riverton, Wyo.) – A Landspout was spotted at mile marker 186 along Interstate 80 (between Wamsutter and Rawlins) earlier this afternoon, according to the National Weather Service Forecast Office in Riverton, which posted the photo on Facebook.
According to information about landspouts posted by the NWS:
Bluestein (1985) first used the term “landspout” to identify another type of non-supercell tornado which has similarities to waterspouts. These tornadoes are most common in the Plains states, but the mechanisms responsible for their formation are found in other areas of the country as well.
Landspouts form when pre-existing horizontal circulations are stretched and tilted upward by a developing thunderstorm updraft. As with gustnadoes, landspouts do not usually form from mesocyclones or supercells. In fact, a large number of landspouts are observed before precipitation is visible on radar.
Landspouts are usually visible, unlike gustnadoes, and most have a narrow, rope-like condensation funnel extending from cloud base to the ground. Wall clouds are not usually observed with landspouts, and these tornadoes are typically short-lived and weak.