While northern parts of China felt their first autumnal chill under persistent heavy rain this week, large areas farther south have continued to swelter in summer-like heat. In south-east China, temperatures have climbed steadily since late September under the influence of higher than average pressure to the north-east, reaching the mid-to-high 30Cs during a period when conditions would normally be cooling from about 30C to the mid-20s. Inland areas have neared 40C (104F), with Xiushui, in Jiangxi province, recording 38.9C on Wednesday, about 13C above average for early October.
Overnight warmth has also persisted. In Hong Kong, further heat on Wednesday brought October’s tally of “very hot days” – defined by temperatures remaining above 28C throughout the day – to four, the highest ever recorded for the month. Models suggest the unusual heat across south-east China will last for another eight to 10 days, before colder air pushes in from the north.
In northern China, a much colder air mass clashed with the warmth to produce stubborn, heavy rain. There had been at least 36 hours of continuous rainfall in Beijing as of Thursday afternoon, averaging 68.8mm (2.71in) across the city, with one Daxing district station recording 140.4mm since Wednesday. The persistent rain kept temperatures unusually low; Thursday was Beijing’s coldest early October day since 1951, with a maximum of just 10.6C – about 10-15C below average.
China has experienced numerous extreme rainfall events this year, an increase that can be linked to a warming global climate. For every 1C increase in global temperature, the atmosphere can hold 7% more moisture.
Meanwhile, typhoon activity continues over the Pacific. Tropical Storm Nakri, which formed on Wednesday, has tracked north-east towards Japan over the last few days. However, it is expected to veer east, following a similar path to Typhoon Halong, which is now travelling out into the northern Pacific.
Nakri is forecast to reach typhoon strength as it moves parallel to the southern Japanese coasts this weekend, with gusts up to 105mph (169km/h), before becoming extratropical as it moves into an area of increased vertical wind shear. While Japan’s mainland should avoid the worst of the storm, the Izu Islands south of Tokyo are again likely to face strong winds and heavy rain, compounding damage left by Halong, which tore off roofs, downed power lines and blocked roads.
