Ōmiya climate — normals and trends
Ōmiya (Japan) has a humid subtropical climate (Cfa) under the Köppen-Geiger classification. Its mean annual temperature is 14.1 °C and it receives 1,476 mm of precipitation per year.
These figures are normals computed over 86 complete calendar years, from 1940 to 2025, using ERA5 reanalysis data from the Copernicus programme.
The warmest month is August (25.2 °C on average) and the coldest is January (3.9 °C). Rainfall peaks in September.
Ōmiya averages 21 frost days, 12 hot days (≥ 30 °C) and 147 rainy days per year.
Ōmiya has warmed by +2.1 °C between 1940 and 2025, or +0.25 °C per decade. This trend is statistically significant.
The number of frost days there went from about 39 to 3 per year over the period.
The hottest day of the period reached 35.5 °C (on 2 August 2022) and the coldest -9.2 °C (on 14 February 1967).
Data from ERA5 reanalysis (Copernicus Climate Change Service), redistributed under a CC-BY 4.0 licence. Normals are recomputed whenever the archive is updated.
Climate normals · ERA5
ŌmiyaIbaraki
- coords
- 36.55°, 140.42°
- period
- 1940–2025 · 86 yrs
Mean daily temperature
14.1°C
Average daily high
17.1°C
Average daily low
11.4°C
Annual rainfall
1,476mm
Sunshine / day
8.5h
Mean relative humidity
74%
Average peak wind
16.6km/h
Seasonal range
21.3°C
Frost days (< 0 °C)
21 d/yr
Hot days (≥ 30 °C)
12 d/yr
Rainy days (≥ 1 mm)
147 d/yr
Annual snowfall
19.0 cm
Average feels-like high
16.7 °C
Average feels-like low
10.1 °C
Average peak gust
35.1 km/h
Tropical nights (≥ 20 °C)
72 d/yr
Solar radiation
14.1 MJ/m²
Has the climate changed?
One stripe per year, 1940 to 2025
+2.1 °C
since 1940
+0.3 °C per decade · r² = 0.59 · p = < 0.001
Trend fitted by linear regression (ordinary least squares) on annual means. A trend is shown only when it is statistically significant (p < 0.05).
A climograph overlays rainfall (bars) and temperature (line): the standard reading in climatology, where you can see at a glance whether the warm season is also the dry one.
Records for the period
Hottest day
35.5 °C
2 August 2022
Coldest day
-9.2 °C
14 February 1967
Wettest day
172 mm
26 September 1958
Windiest day
60.8 km/h
1 October 2018
Strongest gust
141.8 km/h
1 October 2018
Hottest feels-like
43.1 °C
2 August 2022
Coldest feels-like
-14.9 °C
5 February 1952
Snowiest day
32.1 cm
8 February 2014
Sunniest day
14.1 h
20 June 1962
Normals computed over complete calendar years 1940–2025.
A specific year
Pick a year and see how it compares to normal — warmer, drier or more extreme than usual?
Across the whole year
Month by month
| High | vs. normal | Precipitation | vs. normal | |
|---|---|---|---|---|
| Jan | 9.1 °C | +1.9 °C | 43 mm | -9 mm |
| Feb | 8.5 °C | +0.9 °C | 6 mm | -56 mm |
| Mar | 12.8 °C | +2.2 °C | 161 mm | +53 mm |
| Apr | 17.0 °C | +1.7 °C | 130 mm | +9 mm |
| May | 20.1 °C | +0.6 °C | 227 mm | +89 mm |
| Jun | 25.7 °C | +3.2 °C | 160 mm | -2 mm |
| Jul | 29.3 °C | +3.1 °C | 82 mm | -89 mm |
| Aug | 30.4 °C | +2.5 °C | 78 mm | -70 mm |
| Sep | 27.7 °C | +3.1 °C | 119 mm | -70 mm |
| Oct | 20.3 °C | +0.8 °C | 135 mm | -38 mm |
| Nov | 15.7 °C | +1.1 °C | 49 mm | -45 mm |
| Dec | 10.9 °C | +1.2 °C | 85 mm | +25 mm |
The year's extremes
What was the weather like that day?
Your birthday, a wedding, a memorable trip: discover the actual weather for any date since 1940.
Frequently asked questions
What is the climate of Ōmiya?
Ōmiya has a humid subtropical climate (Köppen Cfa). Over 1940-2025, the average annual temperature is 14.1 °C and it receives 1,476 mm of precipitation per year.
What is the hottest day ever recorded in Ōmiya?
The hottest day measured in Ōmiya between 1940 and 2025 was 2 August 2022, reaching 35.5 °C.
What is the coldest day in Ōmiya?
The coldest day measured in Ōmiya between 1940 and 2025 was 14 February 1967, at -9.2 °C.
Does it snow in Ōmiya?
Yes. Ōmiya gets on average 19.0 cm of snow per year and has around 21 frost days.
Has the climate of Ōmiya warmed?
Yes: Ōmiya warmed by +2.1 °C between 1940 and 2025, a statistically significant trend.
What is the wettest day in Ōmiya?
The wettest day measured in Ōmiya between 1940 and 2025 was 26 September 1958, with 172 mm of rain in 24 hours.
What was the windiest day in Ōmiya?
The windiest day measured in Ōmiya between 1940 and 2025 was 1 October 2018, with winds reaching 60.8 km/h.
What is the warmest month in Ōmiya?
The warmest month in Ōmiya is August (25.2 °C on average); the coldest is January (3.9 °C).
How much does it rain in Ōmiya?
Ōmiya receives on average 1,476 mm of precipitation per year, spread over about 147 rainy days.
Is it sunny in Ōmiya?
Ōmiya gets on average 8.5 hours of sunshine per day, roughly 3,103 hours per year over 1940-2025.
What is the biggest single-day snowfall in Ōmiya?
The heaviest 24-hour snowfall measured in Ōmiya between 1940 and 2025 was 8 February 2014, with 32.1 cm.
Are there tropical nights in Ōmiya?
Yes: Ōmiya has on average 72 tropical nights per year (temperature staying above 20 °C), over 1940-2025.
What was the most extreme apparent temperature in Ōmiya?
In Ōmiya, between 1940 and 2025, the highest apparent temperature reached 43.1 °C on 2 August 2022, and the lowest was -14.9 °C on 5 February 1952.
Compare Ōmiya with another city
Pick a second city: its normals will be set against these, indicator by indicator.
Nearby cities
The climate around Ōmiya