Temperature records for Nagano
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Nagano, ―
Stations in Nagano
All-time records in Nagano
Records among the stations on this page (statistics as of November 1, 2026).
| Record | Station | Value | Date |
|---|---|---|---|
| Highest temperature | Ueda | 39.0°C | Aug 3, 2025 |
| Lowest temperature | Sugadaira | -29.2°C | Feb 19, 2012 |
| Heaviest daily rainfall | Iida | 325.3 mm | Jun 27, 1961 |
Range of records by station
Each bar is one station: the left dot is its record low and the right dot its record high. The statistical period differs by station, depending on when observations began or the station moved. The dates are on each station's page.
The climate of Nagano
Nagano Prefecture is, first of all, a prefecture known for how severe its cold gets. The record low among the stations covered here is -24.8°C at Matsumoto on January 27, 1900, which ranks 14th from the bottom among all the stations covered on this site. Suwa's -23.1°C on February 18, 1947, ranks 20th, Karuizawa's -21°C on March 1, 1936, 27th, the city of Nagano's -17°C on January 24, 1934, 37th, and Iida's -16.5°C on January 27, 1954, 40th, so every station in the prefecture lines up on the cold end of the national ranking.
Summer records, by contrast, are spread across the decades. The record high among the stations covered here is 38.7°C in the city of Nagano on August 16, 1994, and Matsumoto's 38.5°C dates back to August 2, 1942, while at Iida in the Ina Valley the top 3 highs on record, 38.2°C, 37.7°C, and 38.4°C, were set within a few days, from July 21 to 23, 2026. Karuizawa alone, at an elevation of 999 m, has a record high of 34.2°C, set on July 16, 1946, and as of August 2026 its statistics have no day that reached 35°C.
Differences in elevation matter in normal values too. On the 30-year average for 1996–2025, the August maximum is 31.8°C at Iida and 26.4°C at Karuizawa, a difference of 5.4°C, and the average January minimum at Karuizawa is -8.1°C, 16th from the bottom among all the stations covered on this site. For the share of days with less than 1 mm of precipitation, Matsumoto leads the stations covered here at 75.1% for the year, while Iida has only 68.1%, and the wettest month is July at every station.
Record values in this description are based on data collected as of September 2026, and the normal statistics on the 30 years 1996–2025.
Monthly normals for Nagano (Nagano)
The normals for Nagano represent the stations in Nagano. Normals for the other stations are on each station's page.
Temperature (monthly normals)
The lines show monthly normals: the upper line is the monthly mean of the daily high and the lower line the monthly mean of the daily low, and the middle line is the monthly mean temperature. Touch the point for a month to read its values. Normals are the 1991–2020 average.
Precipitation (monthly normals, mm)
Table of monthly normals
| Month | Mean | High | Low | Precipitation |
|---|---|---|---|---|
| Jan | -0.4 | 3.8 | -3.9 | 54.6 |
| Feb | 0.4 | 5.3 | -3.7 | 49.1 |
| Mar | 4.3 | 10.3 | -0.5 | 60.1 |
| Apr | 10.6 | 17.4 | 4.9 | 56.9 |
| May | 16.4 | 23.2 | 10.9 | 69.3 |
| Jun | 20.4 | 26.1 | 16.1 | 106.1 |
| Jul | 24.3 | 29.7 | 20.5 | 137.7 |
| Aug | 25.4 | 31.1 | 21.5 | 111.8 |
| Sep | 21.0 | 26.2 | 17.2 | 125.5 |
| Oct | 14.4 | 19.7 | 10.3 | 100.3 |
| Nov | 7.9 | 13.4 | 3.4 | 44.4 |
| Dec | 2.3 | 6.9 | -1.5 | 49.4 |
Temperatures are in degrees Celsius (°C) and precipitation in mm. Blank cells have no normal.
Annual mean temperature (1996–2025)
The yearly average of the daily mean temperature (the line is broken in years with many missing values). Observing conditions at Nagano changed on December 4, 2007; June 25, 2008 (for example, a relocation or new instruments), so the statistics may not be continuous across those dates.
The normals listed here are averages over the 30 years from 1991 to 2020. They are fixed values that stay the same until the next revision of the normals, and they show how warm or cold that month usually is in that area.