July 24, 2020
Rainfall over a 24-hour period in Tehran February 25-26 came to a total of 55.5 millimeters (2.2 inches), the largest volume ever to inundate the capital since such records were first kept in 1951. It was just the latest in a series of what have been heavy rain storms, at least heavy for a dry area like Tehran.
Since September 23, when the current precipitation year began, the capital has seen 147.7 millimeters of rain (5.8 inches.) That compares with 186.4 millimeters (7.3 inches) for all of the previous year and 137.9 millimeters (5.4 inches) for the average full year in Tehran.
Rainfall has been abnormally high this year in the country as a whole. Floods have been quite frequent since just before last Now Ruz. The latest flooding came following the heavy rains that hit not just Tehran but many areas of the west, north and southwest. The rain was so heavy in Hamedan province that the Kalan Dam overflowed.