Updated Rainfall Outlook Forecasts Below-Average Winter Precipitation in Nepal

The Department of Hydrology and Meteorology has forecast that rainfall in Nepal is likely to remain below average for the next few months, according to its latest outlook.

The department said that rainfall is expected to remain below normal from January 1 to February 28, based on its updated assessment. Information officer Dinkar Kayastha said Nepal also recorded below-average rainfall in December, and similar conditions are likely to persist in the coming months.

According to the outlook, most parts of the country are likely to receive below-average rainfall during the two-month period. However, northern parts of Sudurpaschim and Karnali provinces, as well as north-western areas of Gandaki Province, may experience a mix of below-average, average and above-average rainfall.

Kayastha said there is a 55–65 percent probability of below-average rainfall in the central parts of Sudurpaschim Province; southern parts of Karnali, Lumbini and Gandaki provinces; most areas of Bagamati Province; central parts of Madhes Province; and western areas of Koshi Province.

Similarly, a 45–55 percent probability of below-average rainfall has been forecast for south-western Sudurpaschim; central Karnali; northern Lumbini; central Gandaki; central Bagamati; eastern and western Madhes; and central and southern parts of Koshi Province.

For the remaining parts of the country, the probability of below-average rainfall stands at 35–45 percent, according to the department’s climate outlook. Preliminary data show that the country as a whole recorded below-average rainfall in December.

Basis of the Outlook

The department said the assessment was prepared based on climate model outputs produced by global and regional climate centres operating under the World Meteorological Organization.

Kayastha said the outlook also takes into account the current status of large-scale climate drivers that influence Nepal’s winter climate, including El Niño–Southern Oscillation (ENSO) conditions in the eastern Pacific Ocean and the Indian Ocean Dipole (IOD).

According to global climate models, the Pacific Ocean is currently in a La Niña phase, which is expected to shift towards neutral conditions by the end of the winter season. The IOD is currently in a neutral phase and is likely to remain neutral throughout the winter.

Kayastha noted that seasonal climate patterns depend on various oceanic and atmospheric systems as well as land-use conditions, and that climate models cannot provide fully reliable forecasts, particularly during seasonal transition periods. -- RSS