WMOD00034

• Contract/Permit #: #94-6
• Applicant: North American Weather
• Project Name: Willow Creek Basin
• Date: 11/1/1994
• Weather Modification - Doc Type: Report

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Februarv 1995

Stonn activity was somewhat low during the month, but a very good stonn was
seeded on the 9th-10th. It produced significant wet snow over the area, with seeding
operations conducted until the temperature structure became too cold for effective
treatment. Heavy snows led to avalanche concerns. By the time temperatures wanned
sufficiently for consideration of resumed seeding, an Avalanche Warning had been
issued, so no additional seeding was conducted. The remainder of the month saw a
sparsity of stonns although one weak system was seeded late in the month. End-of-
month average snowpack water content increased slightly to 97% of nonnal.

Marcb 1995

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Despite fairly frequent stonn occurrence, precipitation across the region
during March was disappointing, about 80% to 90% of nonnal' The stonns were
somewhat unifonnly distributed through the month, but were generally lacking in
significant moisture. The most productive stonns occurred on the 3rd through the 6th,
the 12th and 13th, and on the 25th. A mid-month period of wanner temperatures
resulted in some loss of snowpack water content due to melt. The average snowpack
water content declined to 90 % of nonnal at the end of March.

Anril1995

After a slow start, April saw a series of wet stonns which continued into
May. Seeding operations were conducted at regular intervals through the month,
beginning on the 8th. The most productive stonn periods were the 8th through the 11th,
the 19th-20th and especially the 23rd through the 26th. Wanner temperatures did lead
to some snowmelt runoff, but April saw a significant jump in average snowpack water
content, from 90% at the end of March to 121 % of nonnal at the end of April.

The contractual cloud seeding period ended at the end of April.

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