New Delhi, Aug. 30 -- A death toll in the dozens, floodwater gushing through highways, and the strain on the reservoir capacity of dams make it clear that the past week was unusually rainy in India's northern states and UTs. How unusual was this rain? An HT analysis of India Meteorological Department's (IMD) gridded dataset shows that the past week was around twice as rainy as the rainiest week on the long period average (LPA) chart of India's most northern regions, although there are differences across states. Himachal Pradesh, Uttarakhand, Punjab, and the UT of Jammu and Kashmir have been the worst affected by rain-related disasters in the past week. Therefore, HT checked how unusual the rain was in the week. The conventional way of checking this is by ranking rain across years. This confirms that rain in the four regions was far from usual last week. Rain in the week ending August 29 is ranked the highest for the week since 1901 (earliest available data) in Himachal Pradesh and Punjab, and seventh and eighth highest in Jammu and Kashmir and Uttarakhand. Another conventional way of checking rain's unusual (or usual) nature is by comparing rain in a period one is studying with the average for the same period in the past (called the LPA). IMD currently uses the 1971-2020 average as the LPA for such comparisons. This also shows that the rain in the past week is a big departure from the past. The rain in the week ending August 29 this year is 2-4 times the LPA for the week in the four states and UTs. Clearly, the rain in the past week was unusual for this time of the year in India's northern regions. However, a big departure from the past is also possible without an exceptional amount of rain in absolute terms. This is because conventional methods only compare the weather of a period with the past climate of the same period. If the past climate of a period is dry, a big departure is possible even with relatively less rain in absolute terms. For example, the week ending August 29 is not the rainiest week of the year in any of the four regions. The rainiest week of the year on the LPA chart is the week ending August 7 in Jammu and Kashmir and Punjab and the weeks ending August 14 and August 19 in Himachal Pradesh and Uttarakhand....