Climate averages 1991–2020
Iwamizawa weather
in April.
A cool, moderately wet month: the 7th warmest and the 5th driest of the year.
Long-term climate patterns, not a forecast for a particular trip.
April is a cool month in Iwamizawa: daytime highs average 9.5°C and nights cool to about 0.1°C. By daytime temperature it is the 7th warmest of the 12 months.
Expect about 67 mm of rain on roughly 12 days, which makes April a moderately wet month (the 5th driest of the 12 months). Daylight, from sunrise to sunset, lasts about 13 h 23 min on an average April day.
The nearest other city in this atlas is Ebetsu (20 km away). In April its highs average 9.4°C, about as warm as Iwamizawa, with 66 mm of rain.
Among the 303 cities listed in Japan, Iwamizawa ranks 291st of 303 for the warmest April highs and 4th of 303 for the driest April (rainfall, lowest first). The mean April high of those 303 cities is 16.7°C; Iwamizawa is 7.2°C cooler than that mean.
From April to May, average highs rise by 6.7°C to 16.2°C, and monthly rainfall rises from 67 mm to 83 mm.
The annual picture
April 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
Iwamizawa climate table
| Month | Average highHigh / low | Average low | Precipitation mm/month | Wet days ≥1 mm/day | Daylight hours/dayDaylight h/day |
|---|---|---|---|---|---|
| January | -3.5°C-10.8°C | -10.8°C | 49 | 12.9 | 9.49 h |
| February | -2.5°C-10.0°C | -10.0°C | 43 | 10.8 | 10.510 h |
| March | 1.9°C-5.9°C | -5.9°C | 57 | 11.6 | 11.912 h |
| April, selected | 9.5°C0.1°C | 0.1°C | 67 | 11.8 | 13.413 h |
| May | 16.2°C6.8°C | 6.8°C | 83 | 11.4 | 14.615 h |
| June | 20.1°C11.8°C | 11.8°C | 64 | 9.6 | 15.315 h |
| July | 23.7°C16.3°C | 16.3°C | 113 | 11.5 | 15.015 h |
| August | 24.4°C17.5°C | 17.5°C | 161 | 12.5 | 14.014 h |
| September | 20.8°C13.1°C | 13.1°C | 126 | 13.2 | 12.513 h |
| October | 14.4°C6.3°C | 6.3°C | 92 | 13.6 | 11.111 h |
| November | 6.7°C-0.5°C | -0.5°C | 87 | 16.1 | 9.810 h |
| December | -0.8°C-8.0°C | -8.0°C | 69 | 15.3 | 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
April in nearby cities
- Ebetsu in AprilJapan · 20 kmHigh 9.4°C · Low -0.1°C · 66 mm rain
- Sapporo in AprilJapan · 36 kmHigh 9.2°C · Low -0.1°C · 73 mm rain
- Eniwa in AprilJapan · 37 kmHigh 9.1°C · Low 0.0°C · 66 mm rain
- Chitose in AprilJapan · 43 kmHigh 8.8°C · Low 0.6°C · 70 mm rain
- Otaru in AprilJapan · 61 kmHigh 7.3°C · Low 1.4°C · 66 mm rain
- Tomakomai in AprilJapan · 64 kmHigh 7.5°C · Low 1.0°C · 78 mm rain
- Asahikawa in AprilJapan · 80 kmHigh 7.7°C · Low -1.3°C · 76 mm rain
- Muroran in AprilJapan · 117 kmHigh 7.5°C · Low 1.3°C · 76 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 Iwamizawa) is explained once on the Iwamizawa year overview and on the Sources, method and limits page.