Spatio-temporal variability of binary weather patterns and precipitation amounts of short time intervals during winter period over the north-west Himalaya (NWH)

Spatio-temporal variability of binary weather patterns (precipitation event/no-precipitation event) and precipitation amounts of short time intervals of 15, 24, 48 and 72 hours (h) are examined by analysing data on the observed precipitation amount of 3377 common days of different winters (winter 1993–winter 2015) at 12 stations in the north-west Himalaya (NWH). Surface meteorological variables over the NWH are collected daily at 0300 and 1200 UTC and data on the precipitation amount collected daily at 0300 UTC are taken to conduct this study. Data on the precipitation amount collected at 0300 UTC daily represent the cumulative precipitation amount of a short time interval of the previous 15 h (1200–0300 UTC) hence the precipitation amount of the 15 h time interval is considered in addition to the precipitation amounts of 24, 48 and 72 h time intervals to examine the Spatio-temporal variability of the precipitation amounts at 12 stations over the NWH. The spatio-temporal variability in the binary weather patterns of short time intervals is examined by computing the normalised percentage differences in the observed precipitation events of short time intervals at 11 stations from corresponding observed precipitation events at a reference station and Spatio-temporal variability in the precipitation amount of short time interval at 12 stations is examined by computing Mean Absolute Differences (MADs) and Root Mean Square Differences (RMSDs) of observed precipitation amounts of short time intervals at each station from corresponding observed precipitation amounts at a reference station. Normalised percentage difference in precipitation events and MAD (RMSD) of the precipitation amount of 24 h time intervals at 11 stations from a reference station fall in the range (−) 50.0%–(+) 20.7% and 4.2–7.2 mm (12.2–18.5 mm), respectively. The maximum difference in binary weather patterns is found for 24 h time interval and simultaneous precipitation events are not found up to 72 h time interval at 12 stations over the NWH. The spatial variability of binary weather patterns is found to decrease and the spatial variability of the precipitation amount is found to increase with the increasing length of short time intervals, i.e., 15–72 h. These findings show that binary weather patterns and precipitation amounts of short time intervals exhibit large Spatio-temporal variability over the NWH. Results of this study can be useful for various applications directly (or indirectly) influenced by weather and/or precipitation amounts of short time intervals over the NWH during the winter period.