Some further results of investigations on Quantitative Precipitation Forecasting over selected area in north India

Abstract

The present paper gives results on Quantitative Precipitation Forecasting involving application Lat. 30°N would of the forecasting model to each of the days of two monsoon months, viz., July and September 1962, Further, in order ions, In this to simplify these computations and reduce the computational time, partial divergence tables have been prepared for the triangular grid comprising of Allahabad, Calcutta and Gauhati, which covers the area under investigation. In addition a nomogram has been prepared to facilitate further reduction in computational time in estimating precipitation rates from a knowledge of vertical velocities and moisture content in the vertical. The computation of rainfall made at intervals of twelve-hour period for the two months has then been compared with the actuals which have been evaluated as the arithmetic mean of rainfall recorded by a. representative number of raingauges within this grid.

            The results of this comparison show that the computed amounts are in general, an over estimate over the observed amounts, Although it has not been possible to assess the reasons for such variation, to be of any theoretical importance, the computed values have shown that they account for almost all the actual heavy rainfall situations, this in itself forming an interesting result of the investigations.