The Meteorological Forecasting Division has officially declared the onset of monsoon in Nepal, two days ahead of the official date of the beginning of monsoon.

The monsoon season in Nepal normally begins on June 10 and ends on September 23. However, after statistically analysing the rainfall data of the past 30 years, the Meteorological Forecasting Division and South Asian Climate Outlook Forum have set a new date for the onset and end of monsoon in the country from this year onwards. As per the revised analysis, June 13 is the day of onset of monsoon and that ends on October 2. The average duration of monsoon in Nepal is 105 days.

Average rainfall is projected across the country during the monsoon this year around, according to the MFD and SACOF.

They have also said that flooding, a natural calamity common in monsoon, is less likely to occur in Province 2 compared to previous years. Province 2, which comprises shallow land in the Tarai belt, is one of the worst-hit areas in the monsoon. However, the Tarai and hilly region in the western part of the country is likely to receive more rainfall this year.

MFD, issuing a special bulletin, said that the onset of monsoon has begun in Nepal as eastern parts of the country, including provinces 1, 2 and Bagmati Province, have welcomed the arrival of the season from yesterday. Today, the monsoon reached as far as Lumbini Province and will cover Nepal by tomorrow evening.

Meanwhile, the Flood Forecasting Section of the MFD has issued a notice asking all to remain alert as the monsoon will gradually become more and more active in the upcoming days. Most parts of the country will experience mild to moderate rainfall while few areas will witness heavy downpour.

No severe damages are forecast during the early monsoon.

It has also asked people residing in urban areas to remain alert as sewages that are normally blocked in the summer might be clogged with waste materials.

"The waste materials that have accumulated inside the sewers in urban areas like Kathmandu valley might trigger unwanted flooding.

Everyone is advised to be extra cautious during the time of monsoon," meteorologist Barun Poudyal of MFD told THT.

In Nepal, monsoon enters with the South-eastern wind through the Bay of Bengal that carries cooler moisture-laden air.

A version of this article appears in the print on June 13, 2021, of The Himalayan Times.