Characteristics of lake-effect snowstorms associated with the Great Salt La
ke are described. Using WSR-88D radar imagery, 16 well-defined and 18 margi
nal lake-effect events were identified from September 1994 through May 1998
(excluding June-August), with the former used for more detailed analysis.
Precipitation during the well-defined events was frequently characterized b
y the irregular development of radar echoes over and downstream of the Grea
t Salt Lake. The most commonly observed precipitation structures were solit
ary wind-parallel bands that developed along or near the major axis of the
GSL and broad-area precipitation shields with embedded convective elements
that formed near the southern shoreline.
Regional-scale composite analyses and rawinsonde-derived statistics showed
that the lake-effect events occurred in post frontal westerly to northerly
700-hPa flow following the passage of an upper-level trough and associated
low-level cold front. The lake-effect environment was characterized by limi
ted steering laver (800-600 hPa) directional shear (generally 60 degrees or
less), moist- to dry-adiabatic low-level lapse rates, and small convective
available potential energy (CAPE), although the CAPE may be locally greate
r over the Great Salt Lake. In all events, the lake-700-hPa temperature dif
ference exceeded 16 degrees C, which roughly corresponds to a dry-adiabatic
lapse rate. The lake-land temperature difference was always positive and u
sually exceeded 6 degrees C, indicating significant potential for the devel
opment of land-breeze circulations and associated low-level convergence ove
r the lake. Radar-derived statistics suggest that lake enhancement is stron
gest during periods of northwesterly to northerly flow and large lake-land
temperature differences. These characteristics are compared with those asso
ciated with lake-effect snowstorms of the Great Lakes and implications for
operational forecasting are discussed.