Dry-day rate calendar for January
Period: observations for 1996–2025 (30 years)
This is the month when the difference between the Pacific side and the Sea of Japan side shows most clearly. In the 1996–2025 records, the Pacific side from Kanto to Kyushu has many days without rain or snow, while the Sea of Japan side has many snowy days, and that gap shows directly in the colors of the map.
The "dry-day rate" is the share of years in which a given day had no precipitation (rain or snow) of 1 mm or more (daily rainfall under 1 mm, smoothed over the 4 days before and after).
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.
January at a glance
The station with the highest monthly average dry-day rate in Japan, the national median, and the station with the lowest. The most comfortable stations this month: Chichijima Island / Takanabe / Miyazaki (details in the comfort section below).
Dry-day rates across Japan (January average)
Each dot is 1 station. The highest and lowest stations are labeled on the map, and the top and bottom lists are below.
Daily calendar for major stations
The deeper the amber, the more years that day stayed dry (the colors match the legend above). The table below (averages for the early, middle, and late parts of the month) has the same values.
| Station | Early | Mid | Late | Monthly avg. | 2 days in a row | 3 days in a row | Windy days | Sunshine (avg.) |
|---|---|---|---|---|---|---|---|---|
| Sapporo | 41.1% | 41.9% | 42.3% | 41.8% | 21.0% | 10.4% | 10.5% | 3.0 hours |
| Sendai | 79.8% | 85.0% | 83.5% | 82.8% | 71.3% | 60.9% | 12.1% | 4.9 hours |
| Niigata | 30.5% | 31.2% | 34.7% | 32.2% | 12.3% | 4.9% | 25.9% | 1.8 hours |
| Kanazawa | 21.5% | 29.1% | 25.0% | 25.2% | 8.9% | 3.2% | 35.3% | 2.1 hours |
| Tokyo | 89.8% | 85.9% | 84.6% | 86.7% | 77.7% | 69.6% | 4.8% | 6.3 hours |
| Nagoya | 86.7% | 81.8% | 81.7% | 83.3% | 71.8% | 61.3% | 7.1% | 5.7 hours |
| Osaka | 87.3% | 80.0% | 79.2% | 82.1% | 69.7% | 58.9% | 7.4% | 4.9 hours |
| Hiroshima | 87.8% | 81.2% | 78.5% | 82.4% | 70.5% | 60.2% | 6.1% | 4.7 hours |
| Takamatsu | 87.2% | 79.9% | 77.6% | 81.4% | 68.7% | 57.5% | 10.3% | 4.8 hours |
| Fukuoka | 75.6% | 67.7% | 66.9% | 70.0% | 52.3% | 39.0% | 7.4% | 3.5 hours |
| Kagoshima | 77.7% | 73.0% | 69.4% | 73.2% | 56.6% | 44.0% | 7.2% | 4.4 hours |
| Naha | 67.8% | 67.4% | 66.3% | 67.1% | 46.1% | 31.5% | 50.5% | 3.1 hours |
"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 / 3 days starting that day (counted from the actual consecutive records, not by multiplying each day's share). They are a guide for multi-night trips and outdoor plans. "Windy days" is the share of days with a daily mean wind speed of 5 m/s or more. The sunshine averages include estimates from March 2021 onward at some stations.
Stations with the highest and lowest dry-day rates (January average)
Highest
Maebashi / Kumagaya / Isesaki / Chichibu / Yorii / Kami-Satomi / Kiryu / Sano / Tatebayashi / Kanna
Comfort in January (5 levels)
Based on observations of dry-day rate, sunshine, wind, and temperature for 1996–2025 (30 years), each station is rated on 5 levels of comfort for January. The tables also show the values behind each rating and the factor that lowered it most (the main factor). Some stations with short sunshine records are not rated.
Each dot is 1 station. The colors match the levels in the legend. The top and bottom lists are below.
Most comfortable stations (top)
| Station | Level | Main factor | Dry-day rate | Sunshine (avg.) | Windy days | High (avg.) | Low (avg.) |
|---|---|---|---|---|---|---|---|
| Chichijima Island | Comfortable | None | 72.1% | 4.2 hours | 9.9% | 20.7°C | 15.8°C |
| Takanabe | Good | Cold | 81.9% | 6.3 hours | 1.1% | 12.9°C | 2.1°C |
| Miyazaki | Good | Cold | 81.7% | 6.2 hours | 15.5% | 13.2°C | 3.1°C |
| Hyuga | Good | Cold | 82.5% | 6.0 hours | 0.0% | 12.9°C | 1.6°C |
| Kushima | Good | Cold | 78.6% | 5.7 hours | 1.0% | 13.2°C | 2.6°C |
| Saito | Good | Cold | 81.6% | 6.1 hours | 1.8% | 13.1°C | 1.0°C |
| Aki | Good | Cold | 81.2% | 6.2 hours | 0.0% | 12.0°C | 3.3°C |
| Shimizu | Good | Cold | 80.7% | 5.9 hours | 5.7% | 12.5°C | 5.4°C |
| Hiwasa | Good | Cold | 82.7% | 6.0 hours | 0.7% | 11.9°C | 2.9°C |
| Kochi | Good | Cold | 82.9% | 6.3 hours | 0.1% | 12.2°C | 2.1°C |
Harshest stations (bottom)
| Station | Level | Main factor | Dry-day rate | Sunshine (avg.) | Windy days | High (avg.) | Low (avg.) |
|---|---|---|---|---|---|---|---|
| Rumoi | Harsh | Cold | 34.9% | 1.6 hours | 69.9% | -1.1°C | -7.5°C |
| Karikawa | Harsh | Cold | 22.6% | 1.0 hours | 38.0% | 2.9°C | -1.7°C |
| Noshiro | Harsh | Cold | 32.8% | 1.2 hours | 53.1% | 2.8°C | -2.3°C |
| Esashi | Harsh | Cold | 40.1% | 1.2 hours | 70.1% | 1.8°C | -3.4°C |
| Haboro | Harsh | Cold | 27.6% | 1.7 hours | 42.9% | -1.3°C | -8.4°C |
| Sakata | Harsh | Cold | 21.9% | 1.2 hours | 57.4% | 4.6°C | -0.6°C |
| Akita | Harsh | Cold | 32.7% | 1.3 hours | 46.0% | 3.2°C | -2.1°C |
| Wakkanai | Harsh | Cold | 35.4% | 1.3 hours | 43.0% | -2.5°C | -6.6°C |
| Suttsu | Harsh | Cold | 28.8% | 0.9 hours | 28.8% | -0.2°C | -4.7°C |
| Aomori | Harsh | Cold | 28.6% | 1.6 hours | 26.4% | 1.8°C | -3.5°C |
Stations are ordered by their rating from the observations. "Windy days" is the share of days with a daily mean wind speed of 5 m/s or more, and "Sunshine (avg.)" is the monthly average of daily sunshine hours (including estimates from March 2021 onward at some stations).
Typhoon approaches in January (5 broad areas)
In the confirmed records for 1951–2025, no typhoon approached any area in January.
The 5 areas are Hokkaido, Honshu, Shikoku, Kyushu, and Okinawa and Amami. The Izu and Ogasawara Islands are not included in Honshu (listed separately).
Typhoon approach calendar / Look up past typhoons by date range
What makes January distinctive
When planning a trip, the "share of consecutive days without precipitation" is a better guide than the dry-day rate for each day. In measurements over the 30 years 1996–2025, the January dry-day rate averaged 66.3% nationwide, but the share of 3 straight days without precipitation fell to 40.7%. How much it shrinks differs completely from place to place: Tokyo barely dropped, from 86.7% to 69.6%, while Niigata thinned from 32.2% to 4.9% and Kanazawa from 25.2% to 3.2%. For a multi-night stay, using the 3-day figure as your guide comes closer to what you will actually experience.
The north–south temperature spread also captures the character of this month. Average highs ranged from 21.5°C at Ishigakijima Island to -4.3°C at Nayoro / Wassamu, and Etanbetsu had an average low of -16.2°C. If you are counting on dry winter skies, inland Kanto places such as Maebashi with a dry-day rate of 91.5% or Kumagaya with 91.1% fit; if snowy scenery is the goal, the snowy side such as Takada with 19.9% or Kutchan with 20.5% fits, so the basic assumptions for packing differ entirely. Days with a daily mean wind speed of 5 m/s or more were frequent at Yonagunijima Island (82.9%) / Cape Muroto (78.1%), and southern islands and capes lived side by side with the wind.
The record values in this commentary are as compiled in September 2026, and the normals are based on 1996–2025 (30 years).
Other months and calendars
December calendar February calendar
When to travel calendar (holidays, long weekends, and comfort levels for 12 months at once)
Each station's page also has a 12-month calendar for that station.