WMOD00011

• Applicant: Don Griffith North American Weather Consultants, Inc.
• Sponsor Name: City and County of Gunnison
• Project Name: Cloud Seeding Evaluation
• Title: The Development, Conduct and Evaluation of a Cloud Seeding Program for the Gunnison River Basin, Colorado During the 2003-2004 Season
• Prepared For: City and County of Gunnison
• Prepared By: North American Weather Consultants
• Date: 8/1/2004
• County: Gunnison
• Weather Modification - Doc Type: Report

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TABLE Of CO:-;TEJI;TS (continued)

Appendices

A Notice Orlnlent of Modify Weather
B Historical Cloud Seeding Programs in Colorado

Tahles

2-1 NA we winter cloud seeding criteria ................................................................... 3
2-2 Cloud seeding generator locations ........ ............................................................... 6

3-1 Stann dates and generator usage. 2003-2004 '..'uter year ..................................... 13
3-2a Generator hours for Gunnison County target area, stomlS 1-10........................... 14
3-2b Generator hours for Gunnison County target area, storms 11-20......................... 15

4-1 Precipitation cnntrol sites .................................................................................... 38
4-2 Precipitation targel sites ...................................................................................... 38
4-3 Snow \vater equivalent control sites .................................................................... 46
4.4 Snow '....ater equivalent target sites ...................................................................... 47

Fie:uT"es

2.1 Seeding target area and generator locations ......................................................... 5
2.2 Photo ofa CNG in operation ................. .............................................................. 7
2.3 Visible satellite image .......................... ............................................................... 8
2.4 Upper-air sounding ............................. ................................................................. 9
2.5 Weather radar inlage ............................................................................................ 10

3.1 NRCS SNOTEL plot for Park Cone, CO ............................................................ 17
3.2 NRCS SNOTEL plot for Porphyry Creek, CO.................................................... 18
3.3 NRCS SNOTEL plot for Slumgullion. CO ......................................................... 19
3.4 Maximum and minimum daily temperatures and nonnals at Butte, CO ......P.... 25
3.5 Precipitation and normal values at Butte. CO ..................................................... 25

4.1 Map of2002-2003 cloud seeding operations in Colorado (CWCS) ................... 32
4.2 Actual/Predicted downwind ratios from Utah study............................................ 33
4.3 Double-Mass plot comparing Bluff and Cedar Point. UT ......................._............ 35
4.4 Precipitation target and control sites .................................................................... 37
4.5 Snowpack target and control sites ........................................................................ 46
4.6 Porphyry Creek SNOTEL graph for April 1-16. 2004 ......................................... 48
4.7 Noyember precipitation ........................................................................................ 49
4.8 December preclpltanon ......................................................................................... 50
4.9 January precipitation ............................................................................................. 51
4.10 February precipitation ........................................................................................... 52