A total of 98 weather stations reported record-high monthly temperatures.
Vietnam experienced record October heat (Photo: Thanh Dong).
According to the National Centre for Hydro-Meteorological Forecasting, temperatures across most of the country were significantly higher than the long-term average for October.
Average temperatures in most regions were one to two degrees Celsius above normal. The increase reached two to three degrees Celsius in the north, while parts of the south recorded temperatures 0.5 to one degree higher.
The nationwide average of 26.30 degrees Celsius was the highest October figure in the country's 65-year observation record, dating back to 1961.
During the month, 61 weather stations recorded daily maximum temperatures that equalled or exceeded previous records for the same period.
Meanwhile, 98 stations reported monthly average temperatures matching or surpassing historical records. Of these, 87 were in northern Vietnam, highlighting the exceptional warmth in the region.
From September 28 to October 2, northern Vietnam experienced a widespread heatwave, with maximum temperatures commonly reaching 35-37 degrees Celsius and exceeding 37 degrees in some areas.
It was the first widespread October heatwave in the region since 1991.
What caused the unusual heat?
Meteorological experts attributed the unusually high temperatures partly to a very strong El Nino event.
Meanwhile, cold air activity in October was not strong enough to sustain a prolonged drop in temperatures.
The National Centre for Hydro-Meteorological Forecasting said El Nino was expected to remain very strong from November 2026 to January 2027, with a 96 per cent probability.
In November, average temperatures nationwide are forecast to be one to two degrees Celsius above the long-term average.
Cold air outbreaks are also expected to be weaker than usual. Severe and particularly severe cold spells in northern Vietnam and the north-central region are forecast to arrive later than normal, with fewer cold days overall. However, intense cold spells remain possible, although they are not expected to last long.
