From the beginning of the year to now, the weather has developed in an unpredictable direction. Hot weather came earlier than the multi-year average. The first widespread intense heat wave started from the end of March - about 10-15 days earlier than usual. Also from the end of March to now, many icy rains have continuously appeared in the Northern and Central provinces and cities. Notably, the nature of icy rain tends to be more extreme than the multi-year average.
According to Mr. Nguyen Van Huong - Head of Weather Forecast Department, National Center for Hydro-Meteorological Forecasting, Department of Hydro-Meteorological Forecasting, thunderstorms and lightning storms usually appear during the interseasonal period (April and May and the period of October-October) in the northern provinces, which is not unusual and not uncommon.
With the period in early May 2026, according to preliminary assessments, the phenomenon of hail rain appearing concentratedly in both mountainous, midland and delta areas is a rare occurrence" - Mr. Huong said.
Commenting on the climate trend in the coming time, according to Mr. Huong, 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. Rain and storms tend to be less frequent, but thunderstorms, tornadoes, and hail in the transitional season and localized heavy rains may also appear more often. Localized heavy rain, high intensity in a short period of time may cause flash floods, landslides and urban flooding, especially in mountainous and steep terrain areas" - 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.
Regarding the temperature trend, in May, the temperature across the country is generally 0.5 - 1 degree Celsius higher than the multi-year average, in some places higher.
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.
