Met department to use radiosonde data to predict lightning

Kathmandu, July 1

The Department of Hydrology and Meteorology will soon be able to predict lightning by using radiosonde data, which is expected to improve the existing weather forecasting system.

The DHM informed that three balloons carrying radiosonde will be flown every day, one each from Dharan, Kathmandu and Surkhet at 00:00 GMT (05:45 am Nepal time) to collect data on atmospheric pressure, temperature, and humidity.

“Through the balloons, we will obtain the data required to make forecasts of lightning strikes at least 10 minutes ahead so people can go to safer places,” Risi Ram Sharma, director general at DHM, told The Himalayan Times.

In the last five years, lightning strikes have killed 612 people and injured 1,266.

From April 13 to June 29 this year, 109 lightning strike accidents have been recorded, with 59 people killed, 134 injured, and a loss of property worth Rs 2,435,000. The Department of Hydrology and Meteorology is preparing to use radiosonde to be able to predict lightning strikes 10 minutes to a few hours ahead, giving people enough time to move to a safer place.

Sharma said the DHM would start operating the balloons by next monsoon. DHM has selected three places as radiosonde stations that would receive atmospheric pressure, temperature, and humidity data of the Nepali sky.

Each flight of balloons carrying radiosonde costs 150 to 200 USD. After regular operation the balloons, DHM will form a lightning detection network to conduct a detailed study of lightning strikes and collect data throughout the country in the next phase.

Meteorologist Mani Ratna Sakya said scientists can predict thunder strikes up to one hour ahead by studying cumulonimbus clouds through use radiosonde. He said the increased incident of lightning strikes is a result of climate change.

“With the help of radiosonde, predicting lightning will become easier and more effective, saving hundreds of lives,” he said, adding, “Climate change has caused land surface temperature and air moisture to increase faster, making cumulonimbus clouds hotter, which increases incidents of lightning.”

Sakya suggested to the public to stay indoors during lightning strikes to stay safe. “Lightning bolts are electric currents with a temperature of more than 10,000 degrees, and can easily spread in wet and metallic objects, so people need to stay safe,” he added, “The best way to survive from thunderbolts is to put metal bars from roofs to underground in every household.”

The DHM informed that it has been preparing to install weather radars in three different places throughout the country to predict precipitation from cloud, calculate its motion, and estimate its rain, snow, and hail types.

Ratanagla hill of Surkhet at an altitude of 2,200 m, Ripdikot of Palpa at an altitude of 1800 m, and Nametar Chitre of Udayapur at 2400 m have been selected for installation of weather radars by the start of 2018. Each radar costs at least Rs 300,000,000.