The northern region is currently undergoing an unprecedented cold spell with temperatures hitting a 40-year low.

According to meteorological experts, the current cold spell in the northern region has the lowest temperatures for this period in over 40 years.

1. The northern region is experiencing its coldest spell in nearly 40 years.

The northern region is enduring a series of bitterly cold days, causing significant damage. Many highland areas in the north have seen the formation of ice. Is this cold spell setting a 'record' compared to historical ones, and how long will it last?

Regarding the above content, reporters from Dân trí have had a discussion with Mr. Nguyễn Văn Hưởng, Director of the Climate Forecast Department (National Center for Meteorological and Hydrological Forecasting).

Over the weekend, the northern region experienced an intense and damaging cold spell, considered the most severe cold spell since the beginning of the winter season until now. By now, can you provide a general overview of how this cold spell has affected various regions?

- Starting from the night of 18/2, provinces in the Northern Delta have been affected by a strong cold air mass combined with the activity of the high-level western wind trough, resulting in light rain, heavy rain, and thunderstorms in some areas.From early morning on 19/2, thunderstorms also began to occur in the North Central region.

Based on recorded observations, on 19/2, the Northern Delta experienced a severe and damaging cold spell, and on 20 and 21/2, the situation of harmful cold weather occurred in both the Northern Delta and the North Central region.

Compared to past cold spells during the same period, is this spell considered a 'record'?

According to the forecast from the National Meteorological Center, the average weekly temperature deviation (from 21-28/2/2022) in the Northern and North Central regions is expected to be lower than the multi-year average by about 4-6°C. Therefore, comparing with the 5 years with the lowest deviation during the same period, the upcoming severe and damaging cold spell may have an average temperature value equivalent to the values in those 5 years.

The lowest recorded temperature in this cold spell at the Láng meteorological station (Hanoi) is 8.4°C on 20/2/2022. However, the temperature here in the last week of February 1996 was recorded at 6.2°C on 21/2/1996. Thus, this temperature is not the lowest value in history.

However, it can be preliminarily forecasted that the average temperature in the last week of February 2022 will be one of the 5 years with the lowest values in the observational dataset for the same period in over 40 years.

As predicted, in recent days, temperatures have dropped significantly, bringing intense cold and freezing rain and ice in highland areas. However, the phenomenon of snow, which tourists are interested in, has not occurred yet. So, can you explain under what weather conditions snow and ice occur?

- Ice forms when there is rain under conditions close to the freezing point (0°C). Rainwater collecting on rooftops, branches, etc., will freeze, creating ice.Snow is a form of precipitation of crystalline ice particles under the atmospheric pressure of the Earth. At low temperatures, these crystals precipitate into snowflakes and fall from the clouds.

Thus, ice forms when there is rain under conditions close to the freezing point (0°C). Rainwater collecting on rooftops, branches, etc., will freeze, creating ice.

The phenomenon of snowfall or snow rain is a natural occurrence similar to rain but with precipitation of small ice crystals or a mixture of ice crystals. Snowfall occurs if the near-surface air layer has a temperature close to 0°C, thick enough for ice crystals and snowflakes from clouds to fall without melting into water, forming snowflakes that remain in that state when close to the ground. If the near-surface air layer has a higher temperature, the ice and snow crystals will melt into water vapor before reaching the ground, creating rain.

How long will this cold spell in the North last, and are there any more cold spells in the North from now until the end of February 2022, sir?

- According to assessments, the severe and damaging cold spell is likely to last until the end of 24/2/2022. After that, the temperature tends to warm up, especially during the day, with no likelihood of severe and damaging cold weather from after 24/2 until the end of February 2022.

Thank you, sir!

According to Dân trí