Abstract
An unusual low-precipitation cumulonimbus that developed in northeastern Colorado is photographically documented in some detail. The storm produced at least 12 funnels, mostly at midlevels on the north side of the main updraft. The base of the cloud consisted of a lenticular “bell” that rotated cyclonically, while a couplet of counterrotating storm-scale eddies prevailed aloft. The funnels originated in a region of enhanced shear between easterly low-level flow on the north side of the bell and westerly flow aloft on the north side of a midlevel anticyclonic eddy.
