WanderWhen

Hanoi weather in September

September is a challenging month to visit Hanoi — consider November–December instead. Expect highs around 31°C, lows near 25°C, and about 21.7 days with rain.

3.4 · Poortravel score for September
Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
Avg high
31°C
Avg low
25°C
Rainfall
400 mm
Rain days
21.7
Sunshine
7.8 h/day
Daylight
12.1 h

What to pack for Hanoi in September

  • light, breathable clothing
  • sun protection (hat, SPF 50)
  • a compact umbrella or rain shell — rain is frequent
  • expect humid, sticky conditions

Humidity averages 85%; max daily wind around 14 km/h.

How September compares

January: 8.0/10 JFebruary: 8.0/10 FMarch: 7.6/10 MApril: 5.6/10 AMay: 2.9/10 MJune: 1.8/10 JJuly: 1.8/10 JAugust: 2.5/10 ASeptember: 3.4/10 SOctober: 6.7/10 ONovember: 9.6/10 NDecember: 9.8/10 D

Best months in Hanoi: November–December. See the full best time to visit Hanoi guide.

Hanoi in September: the details

In September, Hanoi sees average daytime highs of 31°C (87°F) and overnight lows of 25°C (77°F). Rainfall totals roughly 400 mm across 21.7 rainy days, and the sun shines about 7.8 hours per day with 12.1 hours of daylight mid-month. Relative humidity averages 85%.

These figures are climate normals computed from the ERA5 weather reanalysis (2019–2024) for Hanoi, Vietnam (21.02, 105.84) — see our methodology. Actual conditions vary year to year.

Where should you go next month?

Get one email a month with the destinations at their seasonal best. Double opt-in, unsubscribe anytime.