Verdict: Excellent month
Hiroshima Weather in September
September runs warm in Hiroshima, with daily highs around 28°C (82°F) and nights near 21°C (70°F). Expect showers on roughly 12 days of the month — rarely trip-ruining, worth planning around. Overall, September is one of the best months of the year to be in Hiroshima.
Average high
28°C / 82°F
Average low
21°C / 70°F
Rain days
~12
Precipitation
161 mm
What to pack for Hiroshima in September
- Summer clothes, plus one light layer for air-con and evenings
- High-SPF sunscreen, sunglasses, and a refillable water bottle
- Rain gear is non-negotiable — expect rain on roughly 12 days
- Comfortable walking shoes — every guide on this site assumes you'll use them
September against the rest of the year
Warmest in Hiroshima: Aug (31°C / 88°F) · Coolest: Jan (9°C / 48°F) · Wettest: Jul (~17 rain days)
9°
1°
Jan
10°
1°
Feb
14°
4°
Mar
18°
8°
Apr
22°
13°
May
25°
18°
Jun
29°
23°
Jul
31°
24°
Aug
28°
21°
Sep
22°
13°
Oct
17°
8°
Nov
11°
2°
Dec
Daily highs / lows in °C · bars show rain days per month · ERA5 climate normals (2020–2024)