Itako climate — normals and trends
Itako (Japan) has a humid subtropical climate (Cfa) under the Köppen-Geiger classification. Its mean annual temperature is 15.4 °C and it receives 1,442 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 (25.8 °C on average) and the coldest is January (5.6 °C). Rainfall peaks in October.
Itako averages 5 frost days, 12 hot days (≥ 30 °C) and 143 rainy days per year.
Itako has warmed by +1.7 °C between 1940 and 2025, or +0.21 °C per decade. This trend is statistically significant.
The number of frost days there went from about 11 to 0 per year over the period.
The hottest day of the period reached 35.0 °C (on 9 August 2016) and the coldest -6.0 °C (on 5 February 1952).
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
ItakoIbaraki
- coords
- 35.93°, 140.55°
- period
- 1940–2025 · 86 yrs
Mean daily temperature
15.4°C
Average daily high
17.9°C
Average daily low
13.1°C
Annual rainfall
1,442mm
Sunshine / day
8.4h
Mean relative humidity
74%
Average peak wind
21.5km/h
Seasonal range
20.2°C
Frost days (< 0 °C)
5 d/yr
Hot days (≥ 30 °C)
12 d/yr
Rainy days (≥ 1 mm)
143 d/yr
Annual snowfall
6.2 cm
Average feels-like high
17.4 °C
Average feels-like low
11.4 °C
Average peak gust
36.0 km/h
Tropical nights (≥ 20 °C)
87 d/yr
Solar radiation
14.4 MJ/m²
Has the climate changed?
One stripe per year, 1940 to 2025
+1.7 °C
since 1940
+0.2 °C per decade · r² = 0.51 · 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
35.0 °C
9 August 2016
Coldest day
-6.0 °C
5 February 1952
Wettest day
175 mm
26 September 1958
Windiest day
76.8 km/h
5 December 2004
Strongest gust
141.8 km/h
1 October 2018
Hottest feels-like
42.2 °C
16 August 2007
Coldest feels-like
-11.9 °C
5 February 1952
Snowiest day
13.9 cm
15 February 1951
Sunniest day
14.0 h
23 June 1940
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 | 10.3 °C | +1.8 °C | 46 mm | -17 mm |
| Feb | 9.9 °C | +1.0 °C | 15 mm | -59 mm |
| Mar | 13.9 °C | +2.1 °C | 172 mm | +57 mm |
| Apr | 17.9 °C | +1.6 °C | 123 mm | +2 mm |
| May | 20.7 °C | +0.6 °C | 215 mm | +82 mm |
| Jun | 25.8 °C | +3.1 °C | 148 mm | -11 mm |
| Jul | 29.6 °C | +3.3 °C | 59 mm | -77 mm |
| Aug | 30.8 °C | +2.7 °C | 43 mm | -68 mm |
| Sep | 28.3 °C | +3.2 °C | 121 mm | -47 mm |
| Oct | 21.0 °C | +0.7 °C | 143 mm | -49 mm |
| Nov | 16.1 °C | +0.3 °C | 63 mm | -42 mm |
| Dec | 12.1 °C | +1.1 °C | 91 mm | +24 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 Itako?
Itako has a humid subtropical climate (Köppen Cfa). Over 1940-2025, the average annual temperature is 15.4 °C and it receives 1,442 mm of precipitation per year.
What is the hottest day ever recorded in Itako?
The hottest day measured in Itako between 1940 and 2025 was 9 August 2016, reaching 35.0 °C.
What is the coldest day in Itako?
The coldest day measured in Itako between 1940 and 2025 was 5 February 1952, at -6.0 °C.
Does it snow in Itako?
Yes. Itako gets on average 6.2 cm of snow per year and has around 5 frost days.
Has the climate of Itako warmed?
Yes: Itako warmed by +1.7 °C between 1940 and 2025, a statistically significant trend.
What is the wettest day in Itako?
The wettest day measured in Itako between 1940 and 2025 was 26 September 1958, with 175 mm of rain in 24 hours.
What was the windiest day in Itako?
The windiest day measured in Itako between 1940 and 2025 was 5 December 2004, with winds reaching 76.8 km/h.
What is the warmest month in Itako?
The warmest month in Itako is August (25.8 °C on average); the coldest is January (5.6 °C).
How much does it rain in Itako?
Itako receives on average 1,442 mm of precipitation per year, spread over about 143 rainy days.
Is it sunny in Itako?
Itako gets on average 8.4 hours of sunshine per day, roughly 3,066 hours per year over 1940-2025.
What is the biggest single-day snowfall in Itako?
The heaviest 24-hour snowfall measured in Itako between 1940 and 2025 was 15 February 1951, with 13.9 cm.
Are there tropical nights in Itako?
Yes: Itako has on average 87 tropical nights per year (temperature staying above 20 °C), over 1940-2025.
What was the most extreme apparent temperature in Itako?
In Itako, between 1940 and 2025, the highest apparent temperature reached 42.2 °C on 16 August 2007, and the lowest was -11.9 °C on 5 February 1952.
Compare Itako with another city
Pick a second city: its normals will be set against these, indicator by indicator.
Nearby cities
The climate around Itako