Weather in Guangzhou in September

A hard month. September is a hard month in Guangzhou, and worth planning around. The heat itself is manageable at 30.9 °C, but 84% humidity is what you will actually feel.

September ranks 9 of 12 in Guangzhou: past the worst of the year but short of December, which is the month to book if the dates are open.

This is wet-season rain: 16 wet days and 6 genuinely heavy ones, which in this climate means concentrated downpours rather than all-day grey. The pattern is usually a clear morning and a loud afternoon, so front-load the day and stop fighting the 3pm hour. Natural fibres and a second shirt for the day. At 84% nothing dries, including you.

What the averages hide

Averages flatten a month, and this one hides a few things: 21 days top 30 °C, making the heat continuous rather than occasional. Across the twenty years measured, the hottest September day reached 34.6 °C and the coldest night fell to 16.5 °C, and the wettest single day dropped 86 mm — roughly 48% of the month's rain in one day.

September is moderately variable: 83 mm in the driest year against 389 mm in the wettest, around an average of 178 mm. Roughly two Septembers in three land near that average, and the third does something else entirely.

Wind is light at 7 km/h, so the temperature on the page is close to the temperature on your skin, and humidity runs at 84%, high enough to notice on the warm days without dominating them.

How September sits in the year

Temperatures hold steady either side: 31.8 °C in August, 30.9 here, 29 in October. Nothing about the timing within the month matters much. Rain is the thing that moves: October brings 10 days less of it, so pushing the dates later buys drier weather.

Daylight in September

12.3 hours of daylight, losing 0.7 hours across the month. That is between Guangzhou's extremes of 13.5 and 10.7 hours, so days are long enough not to constrain the plan.

An inland climate

Despite being inland, the year stays fairly even: 23 °C between the year's warmest afternoons and coldest nights.

How busy it gets

Off season. The genuine off season: cheapest by a distance, with the caveat that some tours and restaurants close entirely.

Crowd levels are estimated from climate desirability and school-holiday calendars, not from visitor numbers.

September in Guangzhou versus nearby

If Guangzhou is one option among several, the nearby comparison is worth making. Shenzhen is close enough to be a coin toss — within a degree on temperature, the same number of rain days. Haiphong is close enough to be a coin toss — within a degree on temperature, 3 days more rain.

So: September is a compromise. December is 46 points better and is what Guangzhou is actually like at its best — worth moving the trip for if that is possible, and worth adjusting expectations for if it is not.

Every month in Guangzhou

See all twelve months in Guangzhou, or where else to go in September.