WMOD00268

• Applicant: CWCB
• Sponsor Name: USBR
• Project Name: Final Report Weather Damage Mitigation Program
• Title: Numerical Simulations of Snowpack Augmentation for Drought Mitigation Studies in the Colorado Rocky Mountains
• Prepared For: USBR - WDMP
• Prepared By: Curt Hartzell, Dr. William Cotton, Joe Busto
• Date: 9/1/2005
• State: CO
• Weather Modification - Doc Type: Scientific Study

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or appended to this report. One good example of this is the link to "Daily
Precipitation Maps" that allows viewing of project area 24-hr simulated no-seed
and seed precipitation maps, and time series graphs of seeding-related
parameters from November 2003 through March 2004. The 'Real-time Forecast"
link allows access to current RAMS forecasts for Colorado.

Real-time RAMS forecast simulations were run once daily to support the
DW 2003-2004 Program's cloud seeding operations. Numerous map and
graphical forecast products at 2-hr intervals through the 48-hr forecast period were
posted on the CSU Web site and available via the Internet to assist WWC in the
seeding operations. There were many forecast products related to the high
temporal and spatial resolution development and evolution of orographic clouds.
cloud base. temperatures in the lower cloud layer. and wind flow to above the
barrier crest. When available. these parameters were used by WWC to help
determine which generators would be utilized. when they would be activated. and
at what rate the Agl nuclei would be generated. Figures 2.10 through 2.13 are
examples of RAMS Grid 3 0000 UTC Forecast Run products: many such products
were available to WWC for cloud seeding decision-making.

Figure 2.10 shows the wind flow and temperature at the 700-mb level (this
height is about 10,000 ft msl. which is near the mountain tops in Colorado). In
addition to the 2-hr forecasts. there is a neat animation feature that allows the user
to watch the wind flow and temperature fields change over lime. (See CSU WEB
site - Real-time Forecast link.) Each full barb on a wind flag represents a wind
speed of 10 knots: a half barb represents 5 knots.

Figure 2.11 shows the surface wind flow and accumulated total precipitation
in millimeters (liquid) as related to the target area. Again. the animation feature
provides estimates on the timing of precipitation within the target area. as well as
the location and amount.

Figure 2.12 shows a west to east cross-section through the target area
along 39.6 degrees N latitude. The fi9ure includes the topography. temperatures
above the terrain in 5'C intervals. relative humidity (%) pattern. and the W-E (u)
component of the wind flow. The highest relative humidity concentrations
(indication of moist air) are on the upwind side of the mountain peaks. The
animation feature allows the user to easily view forecast changes over time in the
relative humidity and temperature aloft out to 48 hours.

Figure 2.13 shows a north to south cross-section through the target area
along -106.0 W longitude. The figure includes the topography. temperatures above
the terrain in 5'C intervals, vertical motion or velocity (w). and the N-S (v)
component of the wind flow. The areas of positive (upward) vertical motion just
above the terrain would be the likely areas for cloud and perhaps precipitation
development. The animation feature allows the user to easily view forecast
changes over time in the vertical motion and temperature aloft out to 48 hours.

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