Shankar Sharma^{1, 2}, Nitesh Khadka^{2, 3,}, Kalpana Hamal^{2, 4}, Binod Baniya⁵, Nirajan Luintel^{1, 6}, Bharat Badayar Joshi^{1, 6}

Understanding the spatial and temporal variation of precipitation is important to identify its driving potential of extreme events that impact on the socio-economic conditions at national and provincial scales. This study presents the spatial and temporal variation of precipitation and the related extreme events in provincial scale using 143 rain-gauge stations across Nepal during 2001–2016. The results show the provincial differences in the precipitation distribution, with the highest precipitation in Province 4 (Bagmati) and lowest in Province 6 (Karnali). The precipitation is in decreasing trend at the national and provincial scale, expect for Province 6. The spatial distribution of precipitation shows the wettest (Lumle) and driest (Manang and Mustang) areas of the country located within the same Province 4. The seasonal cycle reveals the longer period of monsoon in Provinces 1 and 4; meanwhile, a shorter monsoon period was observed in Provinces 6 and 7 (Farwestern). Heavy (R10mm) and extreme precipitation (R25mm) events were higher in those provinces with a more extended monsoon period and vice-versa. The result further shows that the number of Consecutive Dry Day (CCD) spells in all the provinces was higher than the number of Consecutive Wet Day (CWD) spells. The time-series of extreme events (R10mm, R25mm, CDD and CWD) show an inter-annual variation in seven provinces during 2001-2016. The spatial variation of the number of wet and dry spells was reversed for the provinces lying in the eastern and western parts of the country. This study helps to update and upgrade our understanding of precipitation variability and related extremities over different provinces of Nepal, which can further assist the provincial government in disaster management.

monsoon, extreme events, dry day, wet day, province