מזג האוויר בגואנגג'ואו בספטמבר

Regulars quantify the typhoon risk rather than leaving it vague: the chance of one hitting during a specific one-week stay is under 10 percent, even though this month sits inside the peak August-September window for the strongest, signal-8 storms that shut down ferries, schools and casinos. Our row backs the wet, humid reality behind that risk, a striking 286.5mm of rain across 20.3 days, alongside intense heat, 31.5C reading as a hot 37C at 84 percent humidity, over 25.5C nights. Regulars are candid the year-to-year swing is real - some years bring three signal-8 closures in a season, others none at all - with one regular's most recent September described as warm and clear skies on most days despite sitting in typhoon season. The sea holds a very warm 29.8C. The record: 9.3 hours of sun, a 16.7 kph wind and AQI 78.

Regulars describe a real split within the month, early March still cool and prone to fog and pollution haze on the worst days, warming steadily toward a pleasant, neither-hot-nor-cool feel by late March as spring properly arrives. Our row backs that warming, humid read, 24.1C over 16.4C nights feeling 17C, with a wet 119.3mm of rain across 13.9 days and humidity already climbing to 78 percent. Regulars are clear the rain here tends to be occasional spring showers rather than a settled downpour, so a light rain jacket covers most days without ruining plans. Air quality is the other regular caveat, with foggy days in particular flagged as the times pollution reads worst. The record: 6.1 hours of sun, a 15.9 kph wind and AQI 113.

April here is two problems at once. It is the wet heart of the year - our row carries 173.7mm across 15.6 days with only 6.7 hours of sun a day, and regulars describe thunderstorms arriving about three or four in the afternoon, huge and noisy, sometimes over in an hour and sometimes running all night. And from the fifteenth the trade fair starts, which lifts hotel prices sharply and holds them into May, so the date you book around is fixed even though the rain is not. Temperature is mild at 27.3C but reads as 30C on 80 percent humidity. Carry the small umbrella; rain here is daily life rather than an event. The record: 20C nights and AQI 99.

November is the month regulars pick here: dry, mild, mid-twenties, with mornings and evenings cool enough for a light jacket if you are staying more than a few days. Our row agrees on all of that - 24.7C over 17.3C with 36.8mm across 6.1 days against a March and April that are properly wet. Where we cannot follow them is the air. The board's reasoning is that the north wind blows the pollution away in autumn; our AQI column reads 111 this month against 84 in July, so the cleanest air here belongs to the wet season, not the dry one. The record: humidity 70 percent, 7.4 hours of sun - low for a dry month - and a 15.1 kph wind.

December in Guangzhou is the mild end of a Chinese winter: regulars describe 18 to 20C with little difference between day and night, and the whole thing holding steady unless a cold front pushes down from the north, which drops it for a few days. It is also the driest stretch of the year - our row gives 12.8mm across 2.3 days. The clothing advice is unusually precise: locals rarely bother with sweaters, a jacket or a thin one is enough, nobody needs a coat, and this is the one month of the year you can wear a suit here comfortably. For anyone who feels it, layering beats bulk - two T-shirts are warmer than one. Our row's AQI 126 is the season's other cost. The record: 20.3C days that feel like 19C, 12.2C nights and 7.5 hours of sun.