WMOD00282

• Sponsor Name: USBR Technical Serivce Center, River Systems & Meteorology Group
• Project Name: Snow Accumulation Algorithm for the WSR-88D Radar, Version 1
• Title: Snow Accumulation Algorithm for the WSR-88D Radar, Version 1
• Prepared For: USBR
• Prepared By: Arlin B. Super and Edmond W. Holroyd
• Date: 6/1/1996
• State: CO
• Weather Modification - Doc Type: Scientific Study

Appendix

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Figure

APPENDIXES

Optimization technique used to derive the Ze-8 algorithm ...................... 57
Algorithm documentation requirements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 63
Criteria for acceptance of deliverables ..................................... 69

Tasks of the MOU .................................................... 73

Production of the site-specific files used by the Snow Algorithm in the

June 1996 version . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 79

Program OCCTRIM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 85

Program HYSTRIMT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ... . . .. 89
Program POLAR230 .................................................. 99

Program FLIPBYTE .................................................. 105

Comparison between OSF and Reclamation routines .......................... 109

Program RDNX.C .................................................... 115

TABLES

Locations of two Belfort gage sites in the Albany area ....... . . . . . . . . . . . . . . . . . .. 5
Summary of snow storm periods sampled by the volunteer network near Albany,
New York, during the 1995-96 winter ...................................... 6
Locations of six snow observing sites in the Denver area ........................ 8
Summary of significant snowstorm periods sampled by Belfort gages and snowboards
near Denver, Colorado, during the 1995-96 winter. . . . . . . . . . . . . . . . . . . . . . . . . . .. 11
Locations of five Belfort gage sites in the Cleveland area . . . . . . . . . . . . . . . . . . . . . .. 12
Summary of significant snowfall periods sampled by Belfort gages east-northeast
of Cleveland, Ohio, during the 1995-96 winter ........ . . . . . . . . . . . . . . . . . . . . . .. 13
Summary of snow water equivalents for 5 Cleveland gages for the first 2 ,months
of the winter, and for 5 Denver gages for the first 3 months ofthe winter .......... 16
. Summary of results of applying the optimization scheme to the five gages located
east-northeast of Cleveland ............................................. 26
Summary of applying equation (8) to the data set from each Cleveland area gage ..... 27
Summary of results of applying the optimization scheme to five gages in

the Denver area . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 32

FIGURES

1 Plots of three different Ze-8 relationships showing the effect of varying the
~ coefficient while the a. coefficient remains constant . . . . . . . . . . . . . . . . . . . . . . . . .. 22
2 Plots of three different Ze-8 relationships showing the effect of varying the
a. coefficient while the ~ coefficient remains constant . . . . . . . . '. . . . . . . . . . . . . . . . .. 22
3 Scatter plot of 143 pairs of hourly-observed snowfall for Cleveland gage No.1
versus radar-estimated snowfall directly overhead using the relation Ze = 31881.5 .. .. 25
4 Similar to figure 3 except for 235 pairs for Cleveland gage No.2. . . . . . . . . . . . . . . .. 28
5 Similar to figure 3 except for 187 pairs for Cleveland gage No.3. . . . . . . . . . . . . . . .. 28
6 Similar to figure 3 except for 202 pairs for Cleveland gage No.4. . . . . . . . . . . . . . . .. 29
7 Similar to figure 3 except for 218 pairs for Cleveland gage No.5. . . . . . . . . . . . . . . .. 29
8 Scatter plot of 196 pairs of hourly-observed snowfall for Denver gages No. 1 to 3
versus radar-estimated snowfall directly overhead using the relation Ze = 155 81.6 . . .. 34
9 Similar to figure 8 except the Cleveland Ze-8 relationship of figure 3 is
deliberately misapplied to Denver gages No. 1 to 3 ........................... 36
10 Similar to figure 9 except that the Denver Ze-8 relationship of figure 8 is
deliberately misapplied to Cleveland gages No. 1 and 2 ........................ 36

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