Climate averages 1991–2020
Tomakomai weather
in May.
A cool, wet month: the 6th warmest and the 8th driest of the year.
Long-term climate patterns, not a forecast for a particular trip.
May is a cool month in Tomakomai: daytime highs average 12.7°C and nights cool to about 6.7°C. By daytime temperature it is the 6th warmest of the 12 months.
Expect about 109 mm of rain on roughly 12 days, which makes May a wet month (the 8th driest of the 12 months). Daylight, from sunrise to sunset, lasts about 14 h 36 min on an average May day.
The nearest other city in this atlas is Chitose (21 km away). In May its highs average 14.1°C, 1.4°C warmer than Tomakomai, with 95 mm of rain.
Among the 303 cities listed in Japan, Tomakomai ranks 302nd of 303 for the warmest May highs and joint 28th of 303 for the driest May (rainfall, lowest first). The mean May high of those 303 cities is 21.3°C; Tomakomai is 8.7°C cooler than that mean.
From May to June, average highs rise by 4.0°C to 16.7°C, and monthly rainfall falls from 109 mm to 100 mm.
The annual picture
May in context
Monthly precipitation
Average total · mmAverages from hourly ERA5 reanalysis data. Actual weather varies from year to year. How these numbers are calculated
Every month, side by side
Tomakomai climate table
| Month | Average highHigh / low | Average low | Precipitation mm/month | Wet days ≥1 mm/day | Daylight hours/dayDaylight h/day |
|---|---|---|---|---|---|
| January | -2.0°C-7.5°C | -7.5°C | 44 | 7.1 | 9.49 h |
| February | -1.3°C-7.4°C | -7.4°C | 44 | 7.4 | 10.511 h |
| March | 2.2°C-4.0°C | -4.0°C | 63 | 10.3 | 11.912 h |
| April | 7.5°C1.0°C | 1.0°C | 78 | 11.5 | 13.413 h |
| May, selected | 12.7°C6.7°C | 6.7°C | 109 | 11.8 | 14.615 h |
| June | 16.7°C11.6°C | 11.6°C | 100 | 11.3 | 15.315 h |
| July | 20.6°C16.1°C | 16.1°C | 138 | 13.7 | 15.015 h |
| August | 22.5°C18.2°C | 18.2°C | 197 | 14.5 | 13.914 h |
| September | 20.1°C15.1°C | 15.1°C | 177 | 15.0 | 12.513 h |
| October | 14.3°C8.8°C | 8.8°C | 110 | 11.8 | 11.111 h |
| November | 7.3°C2.0°C | 2.0°C | 78 | 10.8 | 9.810 h |
| December | 0.7°C-4.2°C | -4.2°C | 63 | 8.7 | 9.19 h |
Precipitation (rain or snow, as water) is the average of the 30 separate monthly totals. A wet day is a local calendar day with at least 1 mm of precipitation. Daylight is the calculated sunrise-to-sunset length, not measured sunshine.
Compare places
May in nearby cities
- Chitose in MayJapan · 21 kmHigh 14.1°C · Low 6.5°C · 95 mm rain
- Eniwa in MayJapan · 29 kmHigh 15.0°C · Low 6.2°C · 84 mm rain
- Sapporo in MayJapan · 52 kmHigh 16.1°C · Low 6.7°C · 93 mm rain
- Ebetsu in MayJapan · 53 kmHigh 15.8°C · Low 6.5°C · 84 mm rain
- Muroran in MayJapan · 62 kmHigh 13.2°C · Low 7.0°C · 112 mm rain
- Iwamizawa in MayJapan · 64 kmHigh 16.2°C · Low 6.8°C · 83 mm rain
- Otaru in MayJapan · 79 kmHigh 15.1°C · Low 7.0°C · 84 mm rain
- Hakodate in MayJapan · 119 kmHigh 13.9°C · Low 7.7°C · 119 mm rain
Read the numbers correctly
Climate, not a promise.
These patterns help compare months. They cannot tell you the weather on a specific day of your trip.
Sources, method and limitsHow these numbers are made (what the highs, lows and rain days mean, the sources and the model cell used for Tomakomai) is explained once on the Tomakomai year overview and on the Sources, method and limits page.