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<br />Model analyses of convective potential
<br />and cloud-top heights generally agreed with
<br />the observed radar echoes shown in Fig, 8.
<br />The model was able to discriminate among the
<br />different sites; however, all soundings were
<br />unstable and supported convective clouds above
<br />10 km. MESOCU model analyses of 1800 GMT
<br />soundings predicted moderate CPI ranging from
<br />15 to 40 km at all but one site.
<br />
<br />6. SUMMARY AND CONCLUSIONS
<br />
<br />A fast, economical system of objective
<br />analysis and numerical cloud model software
<br />used in weather modification programs to analyze
<br />and predict mesoscale triggering have been
<br />described. The example of the jet streak
<br />triggering of deep convective lines in west
<br />Texas clearly shows the value of mesoscale
<br />rawinsonde observations and the need for high
<br />resolution numerical analysis techniques to
<br />detect and predict the effects of mesoscale
<br />lifting on the development of convective clouds
<br />and precipitation.
<br />
<br />Band pass objective analysis methods
<br />capable of resolving phenomena with wavelengths
<br />of 200 km appear to be successful in detecting
<br />mesoscale vertical motion fields responsible for
<br />triggering relatively small, meso-p scale lines
<br />of convective clouds which are below the reso-
<br />lution of conventional synoptic observations.
<br />These types of anal ys is tools and dense obser-
<br />vation networks are re.quired for more accurate
<br />short-term forecasting and nowcasting and the
<br />evaluation of natural versus seeding effects in
<br />weather modification programs.
<br />
<br />~--- 'c-~
<br />
<br />7. REFERENCES.
<br />
<br />Barnes. S. L.. 1973: Mesoscale objective map analysis using weighted
<br />time series observations. NOAA Tech. Memo. ERL N,SL-62, 60 pp.
<br />[NTIS COM-73-107BI].
<br />
<br />
<br />Byers, H. R., and R. R. Braham, Jr.. 1949: The Thunderstorm,
<br />Washington, D.C., U.S. Government Printing Df~pp.
<br />
<br />Doswell, C. A. Ill, 1977: Cbtainin9 meterologically significant surface
<br />divergence flel ds through the fi ltering property of objective
<br />analysis. Mon. Wea. Rev., 105, BB5-B92.
<br />
<br />Fujita, T., 1963: Analytical mesometerology: A review, severe local
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<br />
<br />Houze. R. A., 1977: Structure and dynll1lics of a tropical squall 1 ine
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<br />Kreitzberg, C. W., and O. J. Perkey. 1976: Release of potential insta-
<br />bil ity, Part I. A sequential pllllle model within a hydrostatic
<br />primitive equation model. J. Atmos. ScL, n, 456-475.
<br />
<br />Maddox, R. A., 1980: An objective technique for separating macroscale
<br />and mesoscale features in meterological data. Mon. Wea. Rev., lOB,
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<br />,19Bl: The structure and life cycle of midlatitude meso-
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<br />Matthews, O. A.. 1980: SuOlnary of clouds and mesoscale forcing observed
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<br />
<br />, and B. A. Silverman, 1980: Sensitivity of convective
<br />cloud 9rowth to mesoscale lifting: A nllllerical simulation of
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<br />
<br />. and J. Henz, 1975: Verification of nllllerleal model
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<br />Riggio. R.. H. Grubb, W. Alexander, et. aI, 1982: Texas HIPLEX slIlI1Iary
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<br />Ucci11 ini, L., 1980: On the role of upper tropospheric jet streaks and
<br />lees ide cyclogenesis in the developnent of low-level jets in the
<br />Great Plains. Mon. Wea. Rev., lOB, 1689-1696.
<br />
<br />Zi pser, E. J., 1969: The role of unsaturated convect ive downdrafts in
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<br />~_Meteor., 8, 799-814.
<br />
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