The National Center for Hydro-Meteorological Forecasting said that the hot low pressure area in the West is tending to develop and expand, gradually replacing the humid air mass of recent days.
On May 22, hot weather began to cover the Northern Delta and southern Phu Tho province. The highest temperature jumped to 35-36 degrees Celsius, in some places above 36 degrees Celsius; air humidity decreased to 50-55%.
By May 23, the affected area will spread throughout the North and the heat intensity will also increase. The highest temperature will fluctuate from 35-37 degrees Celsius, with some places above 37 degrees Celsius.
Humidity continues to drop deeply to 45-50%, causing a feeling of stuffiness and dryness. It is forecasted that this heat wave will continue continuously until the end of May 27, before the area welcomes a cooling thunderstorm, causing the temperature to drop sharply.
Located in the center of the hot low pressure trough, the Northwest provinces, especially Son La, will experience the most extreme weather days.
According to Son La Provincial Hydrometeorological Station, in the two days of May 22-23, this area will experience hot sun and locally intense heat. The highest temperature can reach 36-38 degrees Celsius, with some places exceeding 38 degrees Celsius.
Along with high temperatures, the relative humidity during the day in Son La dropped extremely low, only 30-35%. The hottest hours last from 11 am to 4 pm, concentrated in the areas of Muong La, Phu Yen, Song Ma, Sop Cop and Yen Chau.
From May 24, Son La is likely to face a widespread and prolonged heat wave for many days to come.
In Lao Cai, on May 22, the sun was 34 degrees Celsius during the day, but in the late afternoon and night, mountainous areas still have potential risks of showers and thunderstorms.
In Cao Bang, on May 22, the weather still maintained a cloudy state, with showers and thunderstorms in some places at night and in the morning, intermittent sunshine in the afternoon; temperature from 31-34 degrees C.
From May 23 to May 25, Cao Bang completely stopped raining, starting a series of hot sunny days with the highest common temperature from 34-36 degrees Celsius.
Meteorological experts especially note that on hot sunny days, people need to be wary of the phenomenon of "storm heat" appearing suddenly in the late afternoon.
These thunderstorms form very quickly (only can be predicted 45-60 minutes in advance), but often shed heavy rain, accompanied by thunderstorms, hail and strong gusts of wind that are extremely dangerous.
In addition, hot weather combined with low air humidity increases the risk of fires and explosions in residential areas due to a sharp increase in electricity demand, along with a high risk of forest fires.
Health authorities recommend that people limit prolonged exposure to high outdoor temperatures to prevent dehydration, exhaustion or heat stroke.
