Otaru, Japan experiences average highs of 12°C (54°F) and lows of 7°C (45°F) throughout the year. Rainfall is frequent, averaging about 16 rainy days per month. Average highs have warmed by 1.8°C (3.2°F) across the available records.
Otaru, Japan Weather & Climate 2026
Monthly climate averages for Otaru, Japan. Based on 10-year ERA5 reanalysis data.
Climate Overview
Drier season: Mar–Sep 
Wetter season: Jan–Dec At-a-Glance Climate Summary
Live Weather & Air Quality
Key figures
Climate Score
4.5/10
Best: May, June, July, August, September
UV Index
4
Low
Temperature 12°C / 7°C
Feels Like 10°C / 4°C
Rainy Days 16
Rainfall 111 mm
Sunshine 8 h
Humidity 81%
Wind Speed 22 km/h
Dew Point 6°C
Snow Days 17 days
Frost Days 19 days
Hottest Month
25°C
August
Avg Low20°C
Rain15days
Coldest Month
-5°C
January
Avg High-2°C
Rain21days
Driest Month
11days
April
Avg High9°C
Avg Low3°C
Windiest Month
27 km/h
November (Gusts 49)
Sea Temperature
5°C – 25°C
Warmest water: August (
24.9°C
)
Worst Time to Visit
Consider avoiding January, February, November, December due to very cold temperatures, heavy rainfall.
Sun Position
Sunrise 03:57
Daylight 15.4h
Sunset 19:18
Live conditions—
Otaru on the map · live conditions
Otaru, Japan
- Continent
- Asia
- Country
- Japan
- City
- Otaru
- Population
- 115.3K
- Coordinates
- 43.19°, 141.00°
Seasonal Breakdown
Spring
Mar–May
Avg High 10°C
Avg Low 4°C
Rain 12 days/mo
1/3 best months
Summer
Jun–Aug
Avg High 24°C
Avg Low 18°C
Rain 13 days/mo
3/3 best months
Autumn
Sep–Nov
Avg High 15°C
Avg Low 10°C
Rain 15 days/mo
1/3 best months
Winter
Dec–Feb
Avg High -1°C
Avg Low -4°C
Rain 22 days/mo
Climate Charts
Based on historical averages (2016–2025)
Monthly Temperatures
HighLowShaded bands show the typical range across the available yearly records.
Line chart showing monthly temperatures. Jan: -2°C / -5°C . Feb: -1°C / -5°C . Mar: 3°C / -1°C . Apr: 9°C / 3°C . May: 17°C / 9°C . Jun: 20°C / 14°C . Jul: 25°C / 19°C . Aug: 25°C / 20°C . Sep: 22°C / 16°C . Oct: 15°C / 10°C . Nov: 8°C / 3°C . Dec: 1°C / -2°C .
Monthly Rainfall
Rainfall
Bar chart showing monthly rainfall. Jan: 90 mm. Feb: 80 mm. Mar: 69 mm. Apr: 72 mm. May: 82 mm. Jun: 112 mm. Jul: 112 mm. Aug: 208 mm. Sep: 111 mm. Oct: 125 mm. Nov: 146 mm. Dec: 125 mm.
Monthly Humidity
Humidity
Line chart showing monthly humidity. Jan: 80%. Feb: 78%. Mar: 80%. Apr: 78%. May: 77%. Jun: 84%. Jul: 86%. Aug: 86%. Sep: 82%. Oct: 78%. Nov: 78%. Dec: 80%.
Monthly Wind Speed
Wind SpeedGusts
Bar chart showing monthly wind speed. Jan: 24 km/h . Feb: 24 km/h . Mar: 22 km/h . Apr: 23 km/h . May: 21 km/h . Jun: 19 km/h . Jul: 17 km/h . Aug: 19 km/h . Sep: 20 km/h . Oct: 24 km/h . Nov: 27 km/h . Dec: 27 km/h .
Sunshine
Sunshine
Sunshine: Jan: 7h. Feb: 8h. Mar: 9h. Apr: 10h. May: 10h. Jun: 10h. Jul: 10h. Aug: 9h. Sep: 9h. Oct: 8h. Nov: 7h. Dec: 6h.
Sea Temperature
Sea Temperatureswim
Line chart showing monthly sea temperature. Jan: 6°C . Feb: 5°C . Mar: 5°C . Apr: 8°C . May: 11°C . Jun: 17°C . Jul: 22°C . Aug: 25°C . Sep: 23°C . Oct: 18°C . Nov: 13°C . Dec: 8°C .
UV Index
UV Index
Bar chart showing monthly UV index. Jan: UV 2. Feb: UV 3. Mar: UV 4. Apr: UV 5. May: UV 6. Jun: UV 6. Jul: UV 6. Aug: UV 6. Sep: UV 5. Oct: UV 3. Nov: UV 2. Dec: UV 2.
Monthly Daylight Hours
Daylight12h reference
Monthly Dew Point & Comfort
Dew Point Dry Comfortable Humid Muggy Oppressive
Snow Days
Snow DaysSnowfall
Snow Days: Jan: 27 days. Feb: 24 days. Mar: 14 days. Apr: 2 days. May: 0 days. Jun: 0 days. Jul: 0 days. Aug: 0 days. Sep: 0 days. Oct: 0 days. Nov: 10 days. Dec: 25 days.
Climate Trends
Average highs have warmed by 1.8°C (3.2°F) across the available records. Average rainfall is trending drier by about 10 mm.
2016 to 2025
Avg high Avg rainfall
Climate summary
| Last 12 months | All years | |
|---|---|---|
| Hottest month | Jul 2025 · 28°C | Aug · 25°C |
| Coldest month | Jan 2025 · -3°C | Jan · -5°C |
| Wettest month | Sep 2025 · 201 mm | Aug · 208 mm |
| Windiest month | Dec 2025 · 30 km/h | Nov · 27 km/h |
Month-by-Month Weather Table
January
Wet 
February
Wet March
Poor April
Poor May best
Good June best
Excellent July best
Excellent August best
Excellent September best
Excellent October
Fair November
Wet December
Wet | Month | Temp | Feels Like | Rain | Sun | Humidity | UV | Status | Details |
|---|---|---|---|---|---|---|---|---|
| January | -2°C / -5°C | -6°C / -11°C | 21days (90 mm) Wet | 6.5h Fair | 80% Humid | 1.8 Low | Wet | View Details |
| February | -1°C / -5°C | -6°C / -10°C | 19days (80 mm) Wet | 7.9h Good | 78% Humid | 2.8 Moderate | Wet | View Details |
| March | 3°C / -1°C | -1°C / -6°C | 14days (69 mm) Wet | 8.9h Good | 80% Humid | 3.9 Moderate | Poor | View Details |
| April | 9°C / 3°C | 6°C / -1°C | 11days (72 mm) Wet | 9.7h Good | 78% Humid | 4.9 Moderate | Poor | View Details |
| May best | 17°C / 9°C | 16°C / 6°C | 12days (82 mm) Wet | 10.2h Excellent | 77% Humid | 5.8 High | Good | View Details |
| June best | 20°C / 14°C | 21°C / 13°C | 12days (112 mm) Wet | 9.9h Good | 84% Humid | 6.4 High | Excellent | View Details |
| July best | 25°C / 19°C | 28°C / 20°C | 11days (112 mm) Wet | 10.1h Excellent | 86% Very Muggy | 6.2 High | Excellent | View Details |
| August best | 25°C / 20°C | 28°C / 22°C | 15days (208 mm) Wet | 8.9h Good | 86% Very Muggy | 5.7 High | Excellent | View Details |
| September best | 22°C / 16°C | 22°C / 16°C | 11days (111 mm) Wet | 8.8h Good | 82% Humid | 4.8 Moderate | Excellent | View Details |
| October | 15°C / 10°C | 13°C / 7°C | 15days (125 mm) Wet | 7.9h Good | 78% Humid | 3.1 Moderate | Fair | View Details |
| November | 8°C / 3°C | 4°C / -2°C | 20days (146 mm) Wet | 6.7h Fair | 78% Humid | 2 Low | Wet | View Details |
| December | 1°C / -2°C | -4°C / -8°C | 25days (125 mm) Wet | 5.8h Fair | 80% Humid | 1.6 Low | Wet | View Details |
Compare Nearby City Climates
Frequently Asked Questions
The best months to visit Otaru are May, June, July, August, September, when temperatures are comfortable and rainfall is at its lowest. This is based on 10-year climate averages for Otaru, scoring temperature, rainfall, humidity, and sunshine hours.
The hottest month in Otaru is August, with average daytime highs of 25°C (78°F). Plan outdoor activities for early morning or late afternoon if visiting during this period.
The coldest month in Otaru is January, with average overnight lows of -5°C (23°F). Pack warm layers and expect shorter daylight hours during this period.
The wettest month in Otaru is August, averaging 208mm of precipitation across 15 rainy days. An umbrella or waterproof jacket is essential.
The rainy season in Otaru runs through December, January, November, February, with the heaviest rainfall in December. Based on 10-year averages for Otaru.
Otaru receives approximately 101 sunshine hours per year. The sunniest month is May with around 10 hours. Based on climate data for Otaru.
The least favorable months to visit Otaru are January, February, November, December, primarily due to very cold temperatures, heavy rainfall. For the best conditions, consider May, June, July, August, September instead.
The annual average UV index in Otaru is 4, classified as moderate. Standard sun protection (sunscreen, hat) is recommended during prolonged outdoor exposure.
Average humidity in Otaru is 81%, classified as humid. High humidity makes warm temperatures feel significantly hotter — lightweight, breathable clothing is recommended.
Yes — sea temperatures in July, August, September average 23°C (73°F), which is warm and comfortable for swimming and water activities.
Yes, Otaru receives snow. Months with snowfall average 17 snow days and 41 cm (16 in) of accumulation, with about 19 frost days during winter.
Average wind speeds in Otaru are 22 km/h (14 mph). The windiest month is November with peak winds reaching 27 km/h (17 mph) (gusts up to 49 km/h / 30 mph).
Otaru averages 2 clear-sky days per month with overall cloud cover around 64%. The clearest skies occur in April.
The annual average dew point in Otaru is 6°C (43°F), which feels dry and comfortable. Outdoor activities are comfortable year-round from a humidity standpoint.
Otaru has a Hot-Summer Continental climate, classified as Dfa under the Köppen system. Continental climates experience extreme temperature ranges — hot summers and cold, snowy winters.
The 'feels like' temperature in Otaru ranges from 4°C (39°F) to 10°C (50°F) on average. Wind chill makes winters feel noticeably colder than the actual temperature — layered clothing is recommended.
Yes, June is a great time to visit Otaru. It earns a climate score of 7.7/10 with Excellent.
For June in Otaru, pack Umbrella, Waterproof jacket, Sunscreen (SPF 30+), Sunglasses, Comfortable walking shoes. With average highs of 20°C (69°F) and 12 rainy days, these essentials will keep you comfortable.
Data Source
Climate data derived from ERA5 reanalysis (ECMWF), averaged over 2016–2025. Sea surface temperature from marine reanalysis data. Climate scores and seasonal estimates are computed by WorldStats.
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