Japan · 1991–2020 normal
Iiyama in
December.
Typical December weather in Iiyama: 7°C by day, -2°C at night, 56 mm of rain over 10.5 wet days. These are measured 1991–2020 station normals, not a forecast.
Typical high7°C
Typical low-2°C
Rain56 mm
Wet days10.5
Comfort score 5 this month (May leads the year at 78). Daylight is calculated as 9 h 39 from latitude 36.85°. Open-water sea temperature is 15.4°C (37 km from the place centre).
Event window
Frost-level nights in December
The measured night-time normal is -2°C, so frost is typical rather than exceptional this month.
The evidence behind this page
One month,
from the same station.
- Place identity
- GeoNames 1861838
- NOAA station
- JA000047610 · NAGANO
- Station distance
- 25.2 km from the place centre
- Coverage
- Good coverage · 20 usable years
- Important limit
- Historical climate is not a forecast. Nearby stations can miss mountains, coasts, and local microclimates.