WMOD00310 ‎(2)‎

• Project Name: Sierra Cooperative Pilot Project
• Title: The Characteristics of Evolution of Supercooled Water in Wintertime Storms Over the Sierra Nevada
• Date: 9/9/1988
• Weather Modification - Doc Type: Report

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JOURNAL OF APPLIED METEOROLOGY

. VOLUME 27

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FIa. II. As in Fig. 5, but for 0900 UTe 22 December 1986 to 0900 UTe 23 December 1986.

d. Cutoff/ow or large amplitude shortwave near 400 N:
6-8 January 1985

Supercooled water and precipitation measurements
from Kingvale were available from 0000 UTe 7 Jan-
uary to 0900 UTe 8 January and are presented in
Fig. 15.
The satellite picture and the 500 mb height and tem-
perature contours in Fig. 13 depict the cutoff flow of
the storm. Southerly flow occurred in the prefrontal
region. Within this region, from 0000 to 1500 UTe 7
January, supercooled water was typically 0.40 mm with
peaks to 0.80 mm. Precipitation during this period was
near 0.5 mm h-1 and steady. The top of the 90% relative
humidity contour was near 3 km over Sheridan. The

The central Sierra Nevada had been under the in-
fluence of a long-wave ridge that was located in the
eastern Pacific prior to the 6-8 January storm. As the
wave pattern progressed eastward, a cutoff low formed
at 1400W longitude and 400N latitude. At 1200 UTe
7 January, the cutoff low had moved eastward to the
position shown in Fig. 13.
Figure 14 shows Sheridan rawinsonde time sections
from 12007 January 1985 to 0600 8 January 1985.