Temperature records for Tomakomai (Hokkaido)
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Temperatures over the 3 months before and after
The gray bands show the range that the high (upper band) and the low (lower band) fell within on each day over the 30 years 1996–2025 (between the 10th and 90th percentiles, so about 80% of the 30 years fall within it). The shading between the solid and dashed lines marks days when the high was above normal (warm colors) or below normal (cool colors).
Show the values by date
| Date | Observed high | Observed low | Normal high | Normal low | Range of highs | Range of lows |
|---|---|---|---|---|---|---|
| Aug 1 | 17.8°C | 15.7°C | 23.0°C | 18.1°C | ||
| Sep 1 | 22.1°C | 16.8°C | 23.3°C | 16.8°C | ||
| Oct 1 | 21.2°C | 9.0°C | 19.2°C | 10.0°C | ||
| ― | ||||||
| Dec 1 | 5.4°C | -2.9°C | 0.2–10.6°C | -6.9–0.4°C | ||
| Jan 1 | 1.3°C | -6.9°C | -3.0–4.0°C | -11.0–-2.2°C | ||
| Jan 31 | 0.1°C | -8.6°C | -3.6–3.8°C | -13.4–-3.1°C |
These are statistics compiled from observations for 1996–2025 (30 years), not a weather forecast for any particular day. For the latest forecasts, see the JMA website.
― on the normal curve
Monthly normals for Tomakomai
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 | -3.6 | 0.5 | -8.1 | 38.7 |
| Feb | -3.2 | 0.9 | -7.9 | 37.5 |
| Mar | 0.5 | 4.4 | -3.7 | 53.5 |
| Apr | 5.3 | 9.6 | 1.3 | 75.7 |
| May | 10.0 | 14.1 | 6.6 | 130.8 |
| Jun | 14.0 | 17.3 | 11.5 | 111.6 |
| Jul | 18.2 | 21.0 | 16.1 | 163.5 |
| Aug | 20.4 | 23.4 | 18.0 | 197.5 |
| Sep | 17.8 | 21.7 | 13.8 | 174.9 |
| Oct | 11.5 | 16.2 | 6.4 | 113.2 |
| Nov | 4.9 | 9.2 | 0.2 | 85.7 |
| Dec | -1.2 | 2.8 | -5.4 | 56.6 |
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). This station's observing conditions changed on September 22, 2004; 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.
All-time records
Records are statistics as of November 1, 2026. The statistical period differs by element, depending on when observations began or the station moved.
| Record | Value | Date | Records began |
|---|---|---|---|
| Highest temperature | 35.5°C | Aug 15, 2007 | Apr 1942 |
| Lowest temperature | -21.3°C | Jan 18, 1945 | Apr 1942 |
| Highest daily minimum | 26.0°C | Aug 26, 2023 | Apr 1942 |
| Lowest daily maximum | -10.0°C | Jan 19, 1966 | Apr 1942 |
| Heaviest daily rainfall | 447.9 mm | Aug 1, 1950 | Apr 1942 |
Top 5 highest temperatures
| Rank | Value | Date |
|---|---|---|
| 1 | 35.5°C | Aug 15, 2007 |
| 2 | 33.8°C | Jul 31, 2022 |
| 3 | 33.8°C | Aug 1, 2021 |
| 4 | 33.3°C | Jul 20, 2021 |
| 5 | 33.3°C | Aug 4, 1994 |
12-month dry-day calendar
The dry-day rate is the share of years with no precipitation (rain or snow) of 1 mm or more on that day (daily precipitation under 1 mm, smoothed over 4 days either side). It is based on observations for 1996–2025 (30 years).
The deeper the amber, the more years that day stayed dry (the legend above shows the colors). Each row ends with the monthly average; detailed values are in the monthly table below.
Monthly averages through the year
How the monthly average dry-day rate changes over the 12 months (the axis fits the range of values). The values match the monthly table below.
Monthly table of dry-day rates and climate
| Month | Dry-day rate | 2 days in a row | 3 days in a row | Windy days | Sunshine (avg.) | High (avg.) | Low (avg.) | Comfort |
|---|---|---|---|---|---|---|---|---|
| Jan | 75.8% | 60.0% | 47.4% | 9.3% | 4.7 h | 0.4°C | -8.2°C | Harsh |
| Feb | 74.4% | 59.4% | 47.9% | 8.3% | 5.2 h | 1.1°C | -7.9°C | Harsh |
| Mar | 72.0% | 54.5% | 41.6% | 10.0% | 5.4 h | 4.7°C | -3.5°C | Harsh |
| Apr | 70.7% | 52.7% | 38.5% | 9.4% | 5.9 h | 9.9°C | 1.6°C | Fair |
| May | 67.7% | 49.2% | 35.0% | 6.0% | 5.6 h | 14.4°C | 6.8°C | Good |
| Jun | 70.8% | 54.7% | 41.9% | 4.2% | 4.3 h | 17.7°C | 11.8°C | Comfortable |
| Jul | 65.5% | 48.5% | 36.3% | 3.1% | 3.6 h | 21.7°C | 16.6°C | Good |
| Aug | 61.2% | 42.8% | 30.0% | 6.9% | 3.9 h | 23.9°C | 18.4°C | Good |
| Sep | 65.9% | 48.0% | 34.5% | 11.6% | 5.2 h | 22.1°C | 14.2°C | Comfortable |
| Oct | 69.0% | 49.7% | 35.1% | 11.8% | 5.1 h | 16.3°C | 6.5°C | Good |
| Nov | 69.9% | 51.1% | 36.7% | 9.8% | 4.3 h | 9.4°C | 0.4°C | Tough |
| Dec | 73.5% | 56.8% | 43.7% | 8.1% | 4.2 h | 2.8°C | -5.5°C | Harsh |
"2 days in a row" and "3 days in a row" are the monthly averages of the share of years in which it stayed dry for 2 or 3 days from that day (counted from the actual consecutive records). "Windy days" is the share of days with a daily mean wind speed of 5 m/s or more. Sunshine averages include estimates from March 2021 onward at some stations. The month names link to monthly pages that compare stations across Japan.
Comfort over the 12 months
A guide that rates the comfort of each month on 5 levels from observations of dry-day rate, sunshine, wind, and temperature for 1996–2025 (30 years). The levels are also in the monthly table above.
This station's observing conditions changed on September 22, 2004; December 4, 2007; June 25, 2008 (for example, a relocation or new instruments), so the statistics may not be continuous across those dates.
These are statistics compiled from observations for 1996–2025 (30 years), not a weather forecast for any particular day. For the latest forecasts, see the JMA website.
About the Tomakomai station
This station, at an elevation of 6 m, faces the Pacific Ocean. The 447.9 mm of August 1, 1950, is the highest daily rainfall at any station in Hokkaido, followed by 442.0 mm at Shiraoi and 417.0 mm at Noboribetsu, both in the same Iburi region.
In summer, cool air from the sea flows in easily, and in the normals, even in early August, the warmest time of year, the maximum is 23.5°C, while the maximum in late January is 0.1°C, a gap of only 23.4°C. Even so, it reached 35.5°C on August 15, 2007, the highest record in the Iburi region. The record low is -21.3°C on January 18, 1945, and statistics run from April 1942.
Record values in this description are based on data collected as of September 2026.
Compare and explore
Nearby stations: Sapporo (about 52 km) / Muroran (about 58 km) / Iwamizawa (about 68 km)
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Stations in Hokkaido / Today's national rankings / Trip planning calendar / Pressure changes at Tomakomai