upper-level cyclone [¦ǝp·ǝr ¦lev·ǝl `sī´klōn] METEOROLOGY A cyclonic circulation existing in the upper air, and specifically, as seen on an upper-level constant-pressure chart; often restricted to describe cyclones associated with relatively little cyclonic circulation in the lower atmosphere. Also known as high-level cyclone; low aloft; upper cyclone; upper-level low; upper low. |