isotherm ribbon

isotherm ribbon

[′ī·sə‚thərm ‚rib·ən]
(meteorology)
A zone of crowded isotherms on a synoptic upper-level chart; the temperature gradient is many times greater than normally encountered in the atmosphere.
McGraw-Hill Dictionary of Scientific & Technical Terms, 6E, Copyright © 2003 by The McGraw-Hill Companies, Inc.