The study presented in this paper examines the relationship between satellite‐derived Himalayan snow cover extent in the winter season (December to March) and the amount of summer monsoon rainfall for the period 1971 to 1980. Himalayan snow cover area has been derived from satellite images and northern hemisphere snow cover charts produced by the National Oceanic and Atmospheric Administration‐National Environmental Satellite Service. Indian summer monsoon rainfall was the area‐weighted mean of all meteorological subdivisions of India for the months June through September. The variations of Indian summer monsoon rainfall were compared with the variation of the Himalayan winter snow cover area. There is an inverse relationship (negative correlation) between these two variables, which indicates that more than mean Himalayan winter snow cover area is to be followed by less than normal (India Meteorological Department (IMD)) summer monsoon rainfall over India. The inverse relationships hold true for 8 out of 10 years of the study period. The coefficients of correlation between the Himalayan snow cover area departures from the 10‐year mean and the rainfall departures from IMD normals for all the meteorological subdivisions of India were computed. The negative correlations were found to be maximum in the region between 18°N latitude and the foothills of the Himalayas.

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The northeast monsoon (NEM) over south India plays a vital role in producing light and moderate rainfall events during October through December. Excess NEM rainfall is mainly due to the intensified tropical cyclones and easterly waves from the Pacific east-west troughs over the Bay of Bengal. The main heat source and sink regions of this monsoon season are the western Pacific high and the Siberian high, respectively. Relative variations in the areal extent and intensity of these source and sink regions influence the NEM season by excess or deficient rainfall. Hence, the aim of the present study was to observe the impact of the Siberian high and the western Pacific high on the NEM rainfall in excess and deficient years. For this purpose, dynamic and thermodynamic parameters, the zonal and meridional winds, the velocity potential, the sea surface temperature and the relative humidity of the National Centers for Environmental Prediction and the National Center for Atmospheric Research (NCEP/NCAR) reanalysis data were used for the period 1951-2014. Analysis of these variables revealed the importance of the source and sink regions for the enhancement/reduction of NEM rainfall during excess/deficient years.