According to the National Center for Hydro-Meteorological Forecasting, on May 12, in the Southern region there will be hot sun, in some places intense hot sun with the highest temperature commonly 35 - 36 degrees C, in some places above 37 degrees C as observed at the following monitoring station: Ta Lai (Dong Nai) 38 degrees C. Relatively low humidity commonly 50 - 55%.
The heat wave in the North lasts for about 3 days
The North Central and Central Central regions from May 13 - 14, are forecast to have hot weather with the highest common temperature of 35 - 37 degrees C, especially the western mountainous areas have hot and intense hot weather with the highest common temperature of 36 - 38 degrees C, in some places above 38 degrees C. The lowest relative humidity is commonly from 45 - 50%. Hot weather time from 11 - 16 hours.
The Southern region is hot, the East has places with intense heat with the highest temperature commonly 35 - 37 degrees C, in some places above 37 degrees C. The relative lowest humidity is commonly from 50 - 55%. The hot time is from 12 - 16 hours.
The Northern region on May 13th will have localized hot weather with the highest temperature in some places above 35 degrees Celsius.
On May 14, the North will be hot, with intense heat in some places with the highest temperature commonly 35 - 37 degrees C, in some places above 37 degrees C. The relative lowest humidity is commonly from 50 - 55%. The hot time is from 12 - 16 hours.
The meteorological agency predicts that hot weather in the North is likely to last until around May 15, in the Central region until around May 17 and in the South until around May 15 - 16.
Warning level of natural disaster risk due to hot weather is level 1. Due to the impact of hot and intense heat combined with low humidity in the air, there is a high risk of fires and explosions in residential areas due to increased electricity demand. Hot weather can also cause dehydration for the human body when exposed to high temperatures for a long time.
Note that the forecast temperature in hot weather bulletins and the actual perceived temperature outside can differ from 2 - 4 degrees Celsius, or even higher depending on the condition of the buffer surface such as concrete and asphalt roads.
Summer 2026 is hotter than average
According to Mr. Nguyen Van Huong - Head of Weather Forecast Department, National Center for Hydro-Meteorological Forecasting, Department of Hydro-Meteorological Forecasting, regarding the climate trend in the coming time, it is very likely that El Nino will appear with a probability of about 80 - 90% from mid-2026. El Nino may reach very strong intensity at the end of the year (with a probability of about 20 - 25%) and last until 2027.
This year, hot weather is forecast to be more frequent and intense than the average of many years" - Mr. Huong warned.
A representative of the Weather Forecasting Department said that in the context of global temperatures still maintaining at record highs, according to the World Meteorological Organization's warning, 2026 is likely to continue to be in the group of hottest years since the observation data was available.
From the end of May 2026, hot weather will gradually expand to the entire Northern and Central regions, intensity will increase sharply and maintain peak periods in June - August 2026. From around September 2026, hot weather will tend to gradually decrease but there may still be unusually late hot spells" - Mr. Huong said.
Mr. Huong said that, overall, extreme heat is no longer a strange phenomenon but is becoming an increasingly clear characteristic in the context of climate change and ENSO shifting to a hot phase.
