WMOD00537

• Title: Remote and In Situ Observations of Sierra Nevada Winter Mountain Clouds: Relationsips between Mesoscale Structure, Precipitation and Liquid Water
• Date: 2/2/1988
• Weather Modification - Doc Type: Report

154

JOURNAL OF APPLIED METEOROLOGY

VOLUME 27

height. As these features can be observed prior to cross-
ing the central Sierra, motion can be established and
an estimate of passage across the project area given,
assuming steady state conditions.
Since the relationships presented here were initially
indicated from case study analyses in 1984, a forecast
experirnent based on these principles was prepared. The
experiment was conducted in the Auburn forecast office
during the 1985-86 and 1986-87 sepp field opera-
tions; it tested the forecaster's ability to predict the on-
set, amount, and duration of SL W observed by the
radiorneter at Kingvale. Flueck and Reynolds (1986)

FIG. 13. Sequence of GOES-W enhanced infrared satellite images
for 27 March 1985. Gray scale enhancement is the same as described
for Fig. 3. Cold front position estimated from surface observations.
(a) 0100, (b) 0200, (c) 0400.

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have reported on prelirninary results from the first year
of this experirnent. Forecast skill was demonstrated. A
future article will describe this experiment in more de-
tail and summarize both years of the experiment.
The question arises as to the representativeness of
the cases described here. A study now being completed
by Heggli and Rauber (1987) has reviewed all precip-
itation events in the central Sierra Nevada beginning
with January 1984 and ending with January 1987 for
times in which the radiorneter was operating at King-
vale (usually December through March for each win-
ter). Their study attempts to classify events by storm

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