Marek Kučera 
Record-Breaking Heatwave Scorches Southeast Asia: Vietnam Ties June Temperature Record
In early June 2025, Southeast Asia is experiencing an unprecedented heatwave, with numerous regions recording temperatures that challenge historical highs. On June 1st, Phu Lien in northern Vietnam reached a sweltering 39.5°C, tying its highest June temperature ever recorded. This event is part of a broader pattern of extreme heat affecting tropical regions from Oceania to Africa and the Caribbean.
Nighttime Heat Offers No Respite
The oppressive heat extends into the night, particularly in Vietnam, where temperatures have remained above 30°C in several areas. Notably, Vinh recorded a nighttime low of 31.7°C, while Quy Nhon reported 30.8°C. Such elevated nighttime temperatures exacerbate health risks, as the human body relies on cooler nights to recover from daytime heat stress.
In Hanoi, the capital city, temperatures climbed to between 38°C and 40°C /https://e.vnexpress.net/news/news/environment/northern-central-vietnam-swelter-under-widespread-heat-waves-4893097.html/. The heat intensified on Sunday, with clear skies and strong sunlight recorded as early as 8 a.m., causing temperatures to rise steadily at a rate of 1–1.5°C per hour. By midday, many areas in the north surpassed 37°C. The National Center for Hydro-Meteorological Forecasting attributed this heat wave to a low-pressure area in the west, which triggered the widespread heat across the region.
In the central region, the heat wave began a day earlier than in the north. The combined effects of the western low-pressure zone and hot, dry foehn winds led to temperatures hovering around 35–36°C, with some areas recording higher figures, including places in Thanh Hoa, Nghe An, and Ha Tinh provinces. These conditions were forecasted to persist across provinces from Thanh Hoa to Binh Thuan, with temperatures ranging from 36 to 38°C, and some locations exceeding 39°C.
The heat wave in northern Vietnam was expected to last until Tuesday, with widespread thunderstorms anticipated to bring some relief, especially in the midlands and mountainous regions. In contrast, the central region continued to endure the oppressive heat.
The persistent high temperatures, coupled with elevated humidity levels, have led to dangerously hot and humid nights, particularly in Vietnam, where nighttime temperatures have remained above 30°C in several areas. Such conditions pose significant health risks and strain on infrastructure.
As Vietnam and its neighbors grapple with these extreme conditions, authorities are issuing heat advisories and urging citizens to take precautions to mitigate health risks. The current heatwave serves as a stark reminder of the challenges posed by a warming planet.
Illustration picture. Source: https://en.sggp.org.vn/central-vietnam-gripped-by-intense-heatwave-post110657.html
