Study of Southwest Monsoon Rainfall over Uttar Pradesh during last two decades (2001-2020)

Rainfall is a function of space and time and highly variable in space and time. It is important to study these changes for planning purpose and for improvement in operational weather forecasting. It is therefore necessary to make a planning and proper management of total rainfall amount for the welfare of common men. Accordingly, in this paper, the daily rainfall during June-September (JJAS) of Uttar Pradesh (U. P.) during last two decades (2001-2020) is analyzed.   
            Analysis shows that, east U. P. experienced negative departure during 2001 to 2020 except 2003 (20%), 2008 (17%) and 2019 (02%) and highest negative percentage departure (-47%) in the year 2015 and West U.P. also experienced negative departure 2001 to 2020 except 2003 (32%), 2008 (03%), 2010 (0%) and 2018 (01%) and highest negative percentage departure (-56%) in the year 2014. As regards, whole U.P., it received negative percentage departure from the normal for years 2001 to 2020 except during 2003 (24%), 2008 (12%) and highest negative percentage departure (-47%) in the year 2014. Hence, it may be concluded that during most of the years, Uttar Pradesh witnessed negative percentage departures during last two decades excluding only couple of years as mentioned above. 
The rainfall variability in respect of west U.P., east U.P. and state as whole for the months of July and August is least and for the months for June and September is highest. Overall, for the whole season, rainfall variability is less than 30 percent.  Rainy days during southwest Monsoon over U.P. are around 59-68 days and average intensity of rainfall is about 10mm per day.