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When determining the suitability of a cloud for seeding, the NDCMP has three criteria <br />that a cloud must pass before it can be seeded. First, the cloud top must be colder than <br />about -5°C. Cloud tops warmer than this will not develop much ice. Second the cloud <br />must have a steady updraft in order to provide a continuing supply of the moist air that <br />allows the ice particles to keep growing. Finally, the cloud must not have much natural ice. <br />If the cloud has already developed ice, it does not need to be seeded because nature is <br />already being efficient. So the cloud must have vertical structure above the freezing level, <br />be relatively ice-free, and have an updraft, to be a suitable cloud for seeding (NDCMP <br />2001). <br /> In this study, the C-band radar located in District II at the airport in Stanley, ND <br />(Stanley radar), is compared to a NEXRAD WSR-88D located in Minot, ND (KMBX). <br />The two radars are located approximately 120 km apart from each other. The KMBX radar <br />is a S-band radar, which has a wavelength of 10 cm. The Stanley radar is operates at C- <br />band, which corresponds to a wavelength of 5 cm. Because of the design and modern <br />technology advancements, the KMBX radar is the more sensitive is able to detect weaker <br />intensity echoes associated with new convective growth. Figure 1 shows the location of the <br />Stanley and KMBX radar with respect to each other, and where their coverage overlaps. <br /> Weather radars send out short pulses of energy and then wait for the signal to travel out <br />at the speed of light, hit a target, and then return back to the antenna of the radar. The radar <br />waits an appropriate amount of time and then sends at another pulse. While these pulses <br />are being sent out the radar is rotating about a vertical axis. The pulse travels much faster <br />than the radar rotates, so the pulses can be sent and received essentially at the same location <br />(Rinehart 1997). <br />7 <br />