A climatology of the warm season Great Plains low-level jet using wind profiler observations

Abstract

Hourly observations from the Wind Profiler Demonstration Network during the warm season months of 1991 and 1992 were used to develop a climatology of the low-level jet (LLJ) over the Great Plains of the central United States. The maximum overall frequency of LLJ occurrence was in the southern part of the Great Plains, while the maximum frequency of the stronger LLJs extended farther north and east (Kansas through Nebraska). The mean LLJ duration was about 4 h for the weak jets and 2 h for the strongest jets. This implies that twice-daily radiosonde observations will fail to detect many LLJ events and that the strongest jets are especially likely to be missed. Such concerns are especially important in light of our finding that southerly LLJs represented about one-half of all occurrences of strong, southerly low-level winds over the region. -from Authors