WMOD00400

• Contract/Permit #: 14-06-D-6801
• Title: Structure and Seedability of San Juan Storms
• Date: 11/1/1976
• Weather Modification - Doc Type: Report

V. CASE STUDIES . . . . . . . .

A. Storm of 28-29 December 1976
l.
2.

3.

General description. . .
28 December 1974 Flight: 1555-1800 tiST. .
a. General description.
b. Airflow. . . . . . .
29 December 197L~ Flight 1: 0745-1135 HST.
a. General description. .
b. Airflow. . . . . . . . .
c. Liquid water regions .
d. The upwind cloud edge. .
c. The region over the mOtlTI tains.
f. Orographic lifting south of Pagosa Springs
g. Convection near Pagosa .
h. Possible seeding effects. . . . .
i. Ground observations. . . . . . . .
29 December 1974 Flight 2: 1505-1650 MST.
a. General description. .
b. Airflow. . . . . . . .
c. Ice crystal concentrations

.
. .

4.

B.

Storm of 27-28 January 1975. .
1. General description. .
2. 27 January 1975 Flight 1:
3. 27 January 1975 Flight 2:
4. 27 January 1975 Flight 3:

0829-1051 I<IDT .
1140-1408 }!DT .
1700-1833 }IDT .

C. Storm of 29 January 1975 . .....
1. General description.. ..... .
2. 29 January 1975 Flight 1: 1335-1600.
a. General description. . . . . . .
b. Ice crystal concentrations . . .
c. Top of the cloud layer at 3.9km (flA" in
Fig. C. 7). . . .. .....
d. Cirrus layer . . . . . . . . . .
3. 29 January 1975 Flight 2: 1630-1930
a. General description. .
b. Airflow. . . . . . . .
c. Ice crystal slide samples. .
d. Region over and ahead of the mountains .
e. Region fiB" (1<'ig. C.13) .
f. Region "c" (Fig. C.13) .
g. Surface observations

D. Storm of 30-31 January 1975. .
1. General description. . . .
2. 30 January 1975 Flight 1: 1235-1527 NDT
B. General description. . . . . .
b. Airflmv. . . . . . . . . . . . .
c. Correlation between air motion and ice crystals.
d. Liquid \-later near "A" of Fig. D.3.
e. Ice crystal slide samples. . . . .
f. Ground observations of ice crystalr3.

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