Nantong is warmest in August, averaging 33° by day and 25° at night. The wettest month is July with 316 mm, and the year brings about 1371 mm in total.
Month by month
| Month | High | Low | Rain | Sea | Daylight | Good for |
|---|---|---|---|---|---|---|
| January | 9° | -1° | 50 mm | 6° | 10.1 h | Cool |
| February | 11° | 0° | 70 mm | 6° | 10.8 h | Cool |
| March | 17° | 4° | 99 mm | 10° | 11.8 h | Sightseeing |
| April | 22° | 9° | 75 mm | 15° | 12.8 h | Sightseeing |
| May | 27° | 15° | 87 mm | 20° | 13.6 h | Beach weather |
| June | 31° | 20° | 207 mm | 24° | 14.1 h | Rainy season |
| July | 32° | 25° | 316 mm | 28° | 13.9 h | Rainy season |
| August | 33° | 25° | 136 mm | 30° | 13.2 h | Mild |
| September | 29° | 19° | 153 mm | 27° | 12.2 h | Mild |
| October | 23° | 13° | 87 mm | 22° | 11.2 h | Sightseeing |
| November | 18° | 8° | 69 mm | 16° | 10.3 h | Sightseeing |
| December | 10° | 1° | 22 mm | 9° | 9.9 h | Cool |
High and low are average daily maximum and minimum, rain is typical monthly total, sea is the average surface temperature, daylight is the hours between sunrise and sunset mid-month. Climate normals from NASA POWER and NOAA MUR — averages, not promises.
When to go
Beach weather: May — highs around 27°, nights no colder than 15°, and at most 87 mm of rain in a month. The sea sits at 20–20° then.
Walking the city: March, April, October and November — highs of 17–23° and no more than 99 mm of rain a month.
Wet season: June and July — up to 316 mm in a single month.