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clouds and a failure to develop a significant congests stage until late in the afternoon underthe latter conditions. Drying of the internal boundary layer by free tropospheric entrainmentwas always underway competing with the enhancement occurring at the surface throughmoisture fluxes. This process is described later. Strong convergence associated with seabreeze “collisions” eventually overcame unfavorable conditions resulting in thunderstormdevelopment on such days.We have tried to examine the accuracy of the so-called non-coalescence – nonbreakup(N-N) melting layer model by fitting the model predictions to the L-band windprofiler data taken in Gadanki. Examples for stratified events are shown in Figures 2. Upperplot [Fig.2 (a)] shows the reflectivity data and the middle plot [Fig.2 (b)] shows the Dopplervelocity. In the stratiform region, the ‘bright-band’ in the radar reflectivity seen between 4km- 5 km height represents the melting layer and the height of it depends on the zero degreeisotherm. Almost of the data taken during stratification, show the melting -layer height to bein this region. The melting process could also be visible in the Doppler velocity (along thevertical), which was characterized by a sharp increase in the mean-fall speed of thehydrometeors during the snow-to-rain - transition process. The surface-disdrometer derivedrainfall integral parameters are shown in Fig.2(c). The input to the N-N melting layer modelis either the rain rate or the equivalent radar reflectivity in the rain region just below themelting layer. Assuming a Marshall-Palmer drop size distribution, the measured radarreflectivity just below the melting layer was used to derive N R (D R ) and, using a simple powerlaw formula for the relationship between the velocity and the drop diameter, the model wasevaluated in terms of the radar reflectivity and the Doppler mean velocity. Figure 2(d) showsthe comparisons for 18 May 1999 (2-hr averaged radar reflectivity profiles are compared interms of dBZ/10 in order to use the same x-axis scale as the mean velocity). Such averagingwas considered to be necessary in order to reduce the effect of vertical wind component onthe fall velocity spectra. The spectra so computed are compared with the measurements inFigure 2(e). The same air-density corrections and the same velocity-diameter relationshipswere applied as before. The comparisons are shown for three cases (i) the top of the meltinglayer, (ii) the bright-band peak region and (iii) the rain region just below the melting layer. Inall three cases, the N-N model derived spectra agree well with the measurements. Thisindicates that the velocity dependence on the diameter of melting snowflakes as well as theempirical elements of the model, namely the height variations of the form factor and thewater content is sufficiently accurate to represent the melting layer characteristics inGadanki, at least at L-band. A previous study conducted in the tropics used long-termmeasurements from an S-band vertically pointing Doppler radar to examine the accuracy ofthe N-N model (Thurai et al 2003). A similar conclusion was drawn from the S-band datataken in Singapore, although the analyses were conducted only in terms of the height profilesof dBZ, Doppler mean and the spectrum width. The current results give further evidence forthe validity of the N-N model for retrieval algorithms for climates affected by monsoonseasons, at least at Rayleigh scattering frequencies.ReferencesAwaka, J., Furuhama,Y., Hoshiyama, M., and Nishitsuji, A., Model calculations of scatteringproperties of spherical bright-band particles made of composite dielectrics. J. Radio Res.Lab., 32, 73-87, 1985.Olson, W. S., P.Bauer, N.F.Viltard, D.E. Johnson, W.K. Tao, R. Meneghini, and L.Liao, AMelting-Layer Model for Passive/Active Microwave Remote Sensing Applications. Part I:Model Formulation and Comparison with Observations,J. Appl. Meteor.,40,1145-1163, 2001.Reddy, K.K., Diagnostic study on vertical structure of monsoon Precipitating cloud systems,Indian Journal of Radio & Space Physics , 32, 198-208, 2003.284