KATHMANDU, Aug 5: While rainfall activity has increased across the country in recent days, average monsoon rainfall has still not been recorded as of Monday.
According to meteorologist David Dhakal from the Department of Hydrology and Meteorology (DHM), by now—more than halfway through the monsoon season—around 60 percent of the total seasonal rainfall should have occurred. If that threshold were met, it would be considered average. However, as of Monday evening, only 42.9 percent of the expected rainfall has been recorded. “So, rainfall is still below average, even though activities have increased nationwide in recent days,” said Dhakal.
Dhakal noted that rainfall is currently occurring in the Terai-Madhesh region, but added, “From Tuesday onward, there is little chance of heavy rainfall in Madhesh. However, some rainfall activity may continue for another two to three days.”
WEATHER ALERT: Monsoon to become active again, rain forecast fo...
Even during the peak of this year's monsoon, the actual rainfall has remained below forecast levels. However, the season is not over yet. In Nepal, the highest rainfall usually occurs during July and October. According to meteorologists, less-than-expected monsoon activity over the Bay of Bengal, along with a weaker-than-expected monsoon system, has contributed to the below-average rainfall.
The positioning of the low-pressure trough significantly influences rainfall activity. Although earlier this year meteorologists had predicted above-average rainfall for the season, that forecast has so far not come true. If the rainfall remains below average by the end of the monsoon season, a detailed study will be needed, said Dhakal.
Generally, Nepal’s monsoon enters around June 13 and retreats by October 2. This year, however, meteorologists expect it to retreat earlier than usual. The average rainfall is typically calculated based on a 30-year dataset. Last year, Nepal experienced above-average rainfall during the monsoon. Usually, about 80 percent of annual rainfall occurs during the monsoon season. Most of the monsoon enters Nepal from the Bay of Bengal via India.
In fact, last year’s rainfall even broke records. According to the DHM, on July 8, 2024, Dodhara Chandani in Kanchanpur witnessed the heaviest 24-hour rainfall in the country’s history, recording 624 mm. Previously, the highest 24-hour rainfall occurred in Hetauda on August 13, 2017, with 516.2 mm. A team of meteorologists was dispatched to Dodhara Chandani to study the phenomenon and submitted a report to the DHM.
Meteorologists described the Dodhara Chandani event as cloud burst—a term used for rainfall of 100 mm or more in a single hour. Not just Dodhara Chandani, but two other stations—Hanuman Nagar and Sundarpur in Kanchanpur—also recorded the highest rainfall levels in 2024.
