Above-normal pre-monsoon rainfall recorded in four weeks

Kathmandu, Mar. 28: The country received no winter rainfall this year. However, in the first 27 days of the pre-monsoon period, most of the areas received rainfall exceeding the normal pre-monsoon precipitation.

In the winter season, spanning from December to February, Nepal received only 12.1 mm of rainfall, which was below the average, typically, the average winter rainfall should be 60.1 mm, according to the Department of Hydrology and Meteorology (DHM). Most of the Tarai region remained dry throughout winter in a lack of rainfall for almost six months.

However, during the pre-monsoon season, the country has already received 43.1 mm of the total expected 226.3 mm of rainfall for the entire pre-monsoon season in the first 27 days. 

 According to Sudarshan Humagain, a meteorologist at DHM,  the pre-monsoon season spans from March to May in Nepal. Humagain said the country has already received 19 per cent of the total rainfall, which exceeds more than 60 per cent of the rainfall compared to the corresponding period of the previous year.

Among the 20 rainfall monitoring stations of the DHM, 12 stations have recorded above-normal rainfall in the last 27 days of pre-monsoon. 

The rainfall measuring stations with above-normal rainfall include Taplejung, which recorded 76.8 mm of rainfall, Biratnagar with 52.3 mm of rainfall, Dhankuta with 84.7 mm of rainfall, Dharan with 64.2 mm of rainfall, Okhaldhunga with 36.1 mm of rainfall, Janakpur with 69.7 mm rainfall, Jiri with 56 mm of rainfall, Kathmandu with 39.5 mm rainfall, Simara with 23.3 mm, Pokhara with 55.2 mm, Danga with 19.8 mm, and Dhangadhi with 38.6 mm of rainfall within the four weeks of pre-monsoon.

However, three stations ---Surkhet, Bhairahawa and Jomson received below-normal rainfall within this period. Humagain said, “The global models also show that the pre-monsoon season this year will have above-normal rainfall.”

Madhukar Upadhyay, a climate change expert, said that despite the country receiving rainfall during this pre-monsoon season, the rainfall pattern resembles that of winter rain because the traditional occurrence of rainfall with lightning and thunderstorms is not happening as expected. He added, “There might be a delay in the winter rain this time,” he added.

“Whatever the case may be, the rainfall has come like an elixir for many after a prolonged dry spell, as it benefits summer crops like maize and Chaite Dhan (paddy),” Upadhyay said. 

He added that the precipitation might harm winter crops like wheat and mustard at some point, but it may not be as detrimental as the dry spell.

It is still too early to say whether the country will receive enough rainfall for the remaining pre-monsoon season and summer season. If there is a dry spell again, the maize and paddy crops will dry up, impacting the entire production, he added.

Meanwhile, the country witnessed hundreds of forest fires with the onset of the pre-monsoon season. The dry spell during the winter season led to the spread of forest fires over larger areas. The country also incurred significant losses due to the forest fires. However, the continuous rainfall in the last two weeks has helped to control the forest fires, said Sundar Sharma, an expert on forest fires and under-secretary at the National Disaster Risk Reduction and Management Authority (NDRRMA).

He said, “We cannot be confident that there will not be more forest fires in the coming days as forest fires are often high also in April and May. If the rainfall ceases for another four to five days, there will be chances of forest fires again. But for now, we are relieved due to the continuous rainfall.”

“If the components of the fire triangle—fuel, oxygen and fire—are active at once, forest fires can occur. Currently, the fuel is wet, and even if someone intends to start a fire, it cannot blaze. However, if there are sunny days and the fuel in the forest dries out again, forest fires, primarily caused by human error, may occur,” Sharma added.