Department Predicts Below-Average Rainfall This Monsoon

Kathmandu. The Department of Hydrology and Meteorology has estimated that rainfall in most parts of the country will be below average during the upcoming monsoon season. The Climate Science Division of the department, while releasing the climate outlook for the four-month monsoon season from Jestha 18 to Ashoj 14, has forecast less rainfall and higher maximum and minimum temperatures across the country, meaning it will get hotter.

According to the rainfall forecast, there is a 55 to 65 percent chance of below-average rainfall in the southern parts of Karnali Province, most of Lumbini Province, the eastern parts of Madhesh Province, and the southern parts of Koshi Province. There is also a 45 to 55 percent chance of below-average rainfall in most of Sudurpashchim Province, the western parts of Madhesh Province, and the central parts of Koshi Province.

In the northern parts of Karnali and Koshi provinces, there is a 35 to 45 percent chance of average rainfall, while the department has stated that there is a 35 to 45 percent chance of below-average rainfall in the remaining parts of the country.

Regarding maximum temperatures, the department states that there is a possibility of above-average temperatures across the country. There is a 55 to 65 percent chance of maximum temperatures being above average in the north-eastern parts of Sudurpashchim Province, the northern parts of Karnali, the western parts of Lumbini, the north-eastern and southern parts of Gandaki, the western parts of Bagmati, the eastern and western parts of Madhesh, and the eastern and southern parts of Koshi. There is a 35 to 45 percent chance of maximum temperatures being above average in the central parts of Koshi and the eastern parts of Sudurpashchim, while the possibility is 45 to 55 percent above average in the remaining areas.

Similarly, there is also a possibility of minimum temperatures being above average across the country. There is a 55 to 65 percent chance of minimum temperatures being above average in the northern parts of Sudurpashchim, Karnali, and Bagmati provinces, the eastern parts of Madhesh, and the southern parts of Koshi. In the southern parts of Karnali, Lumbini, and Gandaki provinces, the central parts of Madhesh, and the central and northern parts of Koshi, minimum temperatures will be above average with a 35 to 45 percent chance. In the remaining parts of the country, this possibility is 45 to 55 percent.

The department has prepared this forecast based on the climate models of global and regional climate information production centers of the World Meteorological Organization and the outlook of the South Asian Seasonal Climate Outlook Forum (SASCOF). The conditions of El Niño-Southern Oscillation (ENSO) developing in the eastern Pacific Ocean and Indian Ocean Dipole (IOD) developing in the Indian Ocean, which affect Nepal's monsoon, have also been taken as a basis. The amount of snow that fell in Europe and Asia during the past winter and pre-monsoon, as well as inter-seasonal variability, have also been considered.

Currently, ENSO is in a neutral state in the Pacific Ocean and is moving towards an El Niño state, and the IOD developing in the Indian Ocean is currently in a neutral state but is expected to reach a positive state by the end of the upcoming monsoon season, according to global model forecasts. Regarding the limitations of the forecast, the department stated, 'It should be noted that seasonal climate depends on various oceanic and atmospheric systems, land use, and other factors, and it is difficult for climate models to predict such systems with 100 percent accuracy during seasonal transitions.'

Reviewing the forecast for the 2082 monsoon last year, the department stated that while the rainfall forecast did not fully match, the temperature forecast was accurate. Last year, although above-average rainfall was forecast in most places, below-average to average rainfall was measured in most centers.

However, regarding temperatures, the department noted that maximum and minimum temperatures were measured above average in most places, as predicted.