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<br />I' <br /> <br />c. WEATHER SURVEILLANCE - SATELLITE, TV, VISUAL AND RADAR <br /> <br />Watching the skies and observing radar is a nearly continuous <br />effort in summer, irrespective of the daily forecast.. In 1992 the <br />im:roduction of a satellite receiver system expanded our capability <br />to observe changing cloud developments in 15-minute intervals. It <br />has since provided us a means to see beyond our radar range, often <br />in real-time. <br /> <br />I <br />I <br /> <br />Earlier in Section B it was mentioned that a TV set in the <br />radar site is used to obtain weather alerts and advisories as the <br />networks make them available to the public. Presented with their <br />advisory and analysis, the networks frequently show a time-looped <br />radar display of storm movements over large areas. This is <br />particularly useful to us in that it gives us a "big picture" in <br />~eal-time to compare against what is seen on our own radar system. <br />Although time-looping can be performed by us on our cloud imagery <br />system, it consumes time to produce it and, generally, it is not as <br />good quality as is the networks'. If our radar system is being <br />attenuated by intervening severe storms, network radar displays can <br />help fill in those blank areas of information. The main problem we <br />encounter is that we are usually very busy during operations and <br />sometimes miss the network station's broadcast when it could be <br />important. <br /> <br />In order to reduce hail effectively, it is extremely important <br />to be able to identify a severe storm early in its growth stage and <br />to begin seeding it as quickly as possible. Recognition of non- <br />severe storms as opposed to potentially destructive ones requires <br />certain expertise. WKWM pilots and meteorologists all soon acquire <br />the ability to be able to visually distinguish between the two <br />types of clouds with a generally high level of reliability which <br />helps get flights launched early. We prefer not waiting to see <br />high radar reflectivities on radar before launching aircraft. Radar <br />lags what actually occurs in rapidly growing clouds because cloud <br />droplet sizes are not large enough to be "seen" until relatively <br />late in the lifetime of such clouds. WKm"1 personnel watch for <br />early development of storms so as to be able to deploy quickly. <br /> <br />Radar becomes an indispensable tool in the identification and <br />tracking of severe storms once such storms are formed. Groundwater <br />Management District #1 owns all the equipment used on the vlKW11 <br />Program including the 5-centimeter wavelength weather radar system <br />and 5 aircraft. The WKWM radar system is similar to some still in <br />use by the National Weather Service. Our normal operational range <br />is 100 n.m. for both the range-height indicator (RHI), when making <br />vertical cloud height measurements, and the plan-position indicator <br />(PHI) for horizontal viewing. Computer hardware, software and <br />radar were all integrated into a complete system upgrade in 1991. <br />'rhe total system allows us to quickly analyze cloud intensity <br />characteristics for hail potential using 45 dBZ heights to compute <br />a proprietary "hail threshold". The computer board and software <br /> <br />16 <br />