AI-generatedKaruizawa at a glance
- Best time
- Apr – May, Sep – Oct
- Warmest month
- Aug · 28°
- Sunshine a year
- 1,960 h
- Rain a year
- 1,473 mm
- Climate
- Continental
- Time zone
- UTC+9
- Elevation
- 952 m
Climate in Karuizawa
Karuizawa has warm to hot summers and cold winters with occasional snow. August is the warmest month with average highs of 28 °C, while January is the coolest at 3 °C. With around 1,960 hours of sunshine a year, Karuizawa is moderately sunny; May is the sunniest month with 6.6 hours a day.
Holiday weather through the year
Best time to visit Karuizawa
The best time to visit Karuizawa is from April to May and from September to October. In September and October, though, the typhoon season is at its peak: check the forecast before you go. Rain is frequent from June to August and from December to March; the wettest month is July with 213 mm.
Karuizawa through the seasons
How the weather changes over the seasons, with averages for each.
Karuizawa in spring
Mar – May
Fair
- 9–21 °C by day
- 6.4 h of sun a day
- 42 rainy days in all
Karuizawa in summer
Jun – Aug
Fair
- 24–28 °C by day
- 5.2 h of sun a day
- 61 rainy days in all
Karuizawa in autumn
Sep – Nov
Fair
- 12–24 °C by day
- 4.7 h of sun a day
- 39 rainy days in all
Karuizawa in winter
Dec – Feb
Poor
- 3–6 °C by day
- 5.2 h of sun a day
- 41 rainy days in all
Which month for what?
Beach & swimming
No sea nearby
Sea from 21 °C, warm and mostly dry
Sightseeing & hiking
No month
15–28 °C and not too much rain
Rainy months
Jun – Aug, Dec – Mar
Rainy season or more than 12 rainy days
Snow
Nov – Apr
Snow on 2 or more days
Find your perfect month
Tell us what you like and we rate every month in Karuizawa for you.
Your best months: May – June, September
Based on the climate averages; tap a month to see its details.
Weather in October
Weather in October
Holiday weather in October
Good
Best time to visit: April – May, September – October
October is the peak of the typhoon season Hurricane season
Keep in mindStorm season
A typical day in October
- Morning, 08:00: about 13°
- Midday, 13:00: about 18°
- Afternoon, 16:00: about 17°
- Evening, 20:00: about 13°
- Night, 23:00: about 11°
05:5117:11
Cool evenings: pack a jumper or a jacket.
Estimated from the average high and low: coolest around sunrise, warmest in mid-afternoon.
Light for photos in October
- Golden hour
- Morning 05:35–06:26 · evening 16:36–17:27
- Blue hour
- Morning 05:25–05:35 · evening 17:27–17:37
Golden hour: the sun between 4° below and 6° above the horizon; blue hour: 6° to 4° below it. Times for the 15th of the month; mountains and clouds shift the light.
October in Karuizawa compared with home
Loading the climate at home …
Early or late October?
In October, daytime highs fall from about 21° at the start of the month to 15° at the end. The days get 1.1 h shorter.
| October | 1 Oct | 31 Oct |
|---|---|---|
| Daytime high | 21° | 15° |
| Night-time low | 12° | 6° |
| Daylight | 11.9 h | 10.8 h |
What is the weather like in Karuizawa in October?
In October, Karuizawa is mild: daytime highs average 18 °C, and nights cool down to about 9 °C. Expect around 4.7 hours of sunshine a day. Rain is frequent, with about 12 rainy days and 140 mm in total. All in all, October is a good month for a holiday in Karuizawa.
More details for October
- Daylight
- 11 h 20 min05:51 – 17:11
- UV index
- 5 · moderateclear sky, noon (estimate)All months
- Muggy days
- 0 daysdew point 18 °C or moreAll months
- Wind
- 9 km/haverage daily peakAll months
- Cloud cover
- 68 %on averageAll months
- Hot days
- 0 days30 °C or moreAll months
- Snow days
- 0 days1 cm or more of fresh snowAll months
- Time zone
- UTC+9offset from UTC
How the score comes together
- Temperatureweight 50 %100 %
- Sunshineweight 20 %28 %
- Few rainy daysweight 30 %41 %
Each factor is rated from 0 to 100 % and weighted for the travel style “City break”.
What to pack in October
- Sunscreen
- A jumper for the evenings
- Rain jacket or umbrella
Compare two months in Karuizawa
Pick two months to see how the weather differs. A tick marks the clearly better value; for temperatures it depends on your plans.
October and May bring similar holiday weather to Karuizawa (score 68 and 70). In May, days are 3 °C warmer than in October. May has 2 more rainy days. The sun shines 2 hours longer a day in May.
| Month | October | May |
|---|---|---|
| Holiday weather score | 68 | 70 |
| Daytime high | 18° | 21° |
| Night-time low | 9° | 10° |
| Sunshine | 4.7 h | 6.6 hbetter |
| Rainy days | 12better | 14 |
| Rainfall | 140 mm | 131 mm |
Based on the climate averages 1996–2025.
Karuizawa month by month
The typical weather for every month at a glance.
14January3° · 5.1 h
In January, Karuizawa is cold: daytime highs average 3 °C, and nights often drop below freezing (−5 °C). Expect around 5.1 hours of sunshine a day. Precipitation falls on about 15 days, totalling 73 mm; on about 13 of them it snows. All in all, January is not an ideal month for a holiday in Karuizawa.
Karuizawa in January19February4° · 5.6 h
In February, Karuizawa is cold: daytime highs average 4 °C, and nights often drop below freezing (−5 °C). Expect around 5.6 hours of sunshine a day. Rain is frequent, with about 13 rainy days and 73 mm in total. Snow falls on about 11 days. All in all, February is not an ideal month for a holiday in Karuizawa.
Karuizawa in February22March9° · 6.0 h
In March, Karuizawa is cold: daytime highs average 9 °C, and nights often drop below freezing (−2 °C). Expect around 6.0 hours of sunshine a day. It rains often – on about 14 days, adding up to 106 mm. Snow falls on about 9 days. All in all, March is not an ideal month for a holiday in Karuizawa.
Karuizawa in March60April16° · 6.5 h
In April, Karuizawa is cool: daytime highs average 16 °C, and nights cool down to about 4 °C. The sun shines for around 6.5 hours a day. Rain is frequent, with about 13 rainy days and 106 mm in total. Snow falls on about 3 days. All in all, April is a good month for a holiday in Karuizawa.
Karuizawa in April70May21° · 6.6 h
In May, Karuizawa is mild: daytime highs average 21 °C, and nights cool down to about 10 °C. The sun shines for around 6.6 hours a day. It rains often – on about 14 days, adding up to 131 mm. All in all, May is a good month for a holiday in Karuizawa.
Karuizawa in May56June24° · 4.9 h
In June, Karuizawa is warm: daytime highs average 24 °C, and nights cool down to about 14 °C. Expect around 4.9 hours of sunshine a day. It rains often – on about 18 days, adding up to 169 mm. All in all, June is a so-so month for a holiday in Karuizawa.
Karuizawa in June54July28° · 5.0 h
In July, Karuizawa is hot: daytime highs average 28 °C, and nights cool down to about 19 °C. Expect around 5.0 hours of sunshine a day. It rains often – on about 22 days, adding up to 213 mm. On about 7 days the thermometer climbs to 30 °C or more. The air is often humid and muggy. All in all, July is a so-so month for a holiday in Karuizawa.
Karuizawa in July51August28° · 5.8 h
In August, Karuizawa is hot: daytime highs average 28 °C, and nights cool down to about 19 °C. Expect around 5.8 hours of sunshine a day. It rains often – on about 20 days, adding up to 159 mm. On about 9 days the thermometer climbs to 30 °C or more. The air is often humid and muggy. All in all, August is a so-so month for a holiday in Karuizawa.
Karuizawa in August60September24° · 4.5 h
In September, Karuizawa is warm: daytime highs average 24 °C, and nights cool down to about 16 °C. Expect around 4.5 hours of sunshine a day. It rains often – on about 16 days, adding up to 160 mm. All in all, September is a good month for a holiday in Karuizawa.
Karuizawa in September68October18° · 4.7 h
In October, Karuizawa is mild: daytime highs average 18 °C, and nights cool down to about 9 °C. Expect around 4.7 hours of sunshine a day. Rain is frequent, with about 12 rainy days and 140 mm in total. All in all, October is a good month for a holiday in Karuizawa.
Karuizawa in October42November12° · 4.8 h
In November, Karuizawa is cool: daytime highs average 12 °C, and nights cool down to about 3 °C. Expect around 4.8 hours of sunshine a day. Rain is frequent, with about 11 rainy days and 75 mm in total. Snow falls on about 2 days. All in all, November is a so-so month for a holiday in Karuizawa.
Karuizawa in November17December6° · 5.0 h
In December, Karuizawa is cold: daytime highs average 6 °C, and nights often drop below freezing (−2 °C). Expect around 5.0 hours of sunshine a day. Rain is frequent, with about 13 rainy days and 69 mm in total. Snow falls on about 10 days. All in all, December is not an ideal month for a holiday in Karuizawa.
Karuizawa in DecemberClimate in detail
Year & climate table
Climate through the year
Long-term monthly averages. Tap a month to see its details.
Nights and sleep in Karuizawa
How warm the nights get in each month, from the mean night-time low. Tap a month for details.
- Frost below 0°
- Cold 0–8°
- Cool 8–15°
- Pleasant 15–20°
- muggy month (15+ muggy days)
CoolOctober: nights around 9°. A duvet at night and a jumper for the evening.
The coolest nights are in January (−5°), the warmest in August (19°). Nights are pleasant for sleeping (15 to 20 °C) from July to September. Nights fall below 8 °C on average from November to April, so the room should be heated. It is muggy (dew point 18 °C or more) on about 52 days a year, mostly from July to August.
Temperatures through the year
Average daytime high, night-time low and sea temperature per month.
| Month | Score | Day | Night | Sun | Rain days | Rain mm |
|---|---|---|---|---|---|---|
| JanuaryJan | 14 | 3° | −5° | 5.1 h | 15 | 73 |
| FebruaryFeb | 19 | 4° | −5° | 5.6 h | 13 | 73 |
| MarchMar | 22 | 9° | −2° | 6.0 h | 14 | 106 |
| AprilApr | 60 | 16° | 4° | 6.5 h | 13 | 106 |
| MayMay | 70 | 21° | 10° | 6.6 h | 14 | 131 |
| JuneJun | 56 | 24° | 14° | 4.9 h | 18 | 169 |
| JulyJul | 54 | 28° | 19° | 5.0 h | 22 | 213 |
| AugustAug | 51 | 28° | 19° | 5.8 h | 20 | 159 |
| SeptemberSep | 60 | 24° | 16° | 4.5 h | 16 | 160 |
| OctoberOct | 68 | 18° | 9° | 4.7 h | 12 | 140 |
| NovemberNov | 42 | 12° | 3° | 4.8 h | 11 | 75 |
| DecemberDec | 17 | 6° | −2° | 5.0 h | 13 | 69 |
Climate averages 1996–2025 (sunshine partly WMO station normals 1991–2020), not a forecast. Data: Copernicus ERA5 / ERA5-Land via Open-Meteo.com (CC BY 4.0), NOAA OISST, WMO 1991–2020 (NOAA NCEI), GeoNames (CC BY 4.0). Sources & licences
36.35° N, 138.63° E · 952 m · Asia/Tokyo
Sunshine
Sunshine hours in Karuizawa
Average hours of bright sunshine per day, next to the length of the day. Tap a month to select it.
In October, the sun shines for about 4.7 of 11.3 hours of daylight in Karuizawa, 42 % of the daylight hours.
Sunshine hours: estimated from radiation data (ERA5, 1996–2025) and calibrated against measured station values; no weather station is close enough here. Daylight is the time from sunrise to sunset on the 15th of the month.
Rain
Rain in Karuizawa: rainy days and rainfall
A rainy day is a day with at least 1 mm of rain or snow; the amount is what falls in the whole month. Tap a month to select it.
In October, Karuizawa has about 12 rainy days with 140 mm of rain in total.
UV index
UV index in Karuizawa
How strong the sun is at noon, month by month, and how quickly unprotected skin burns.
- Clear-sky UV in October
- 5 · moderateAround midday seek shade; use sunscreen, a hat and sunglasses.
The sun is strongest in June (UV 11).
Minutes until sunburn in October
- Very fair skin
- about 25 min
- Fair skin
- about 30 min
- Light brown skin
- about 45 min
- Olive skin
- about 60 min
Rough guide for unprotected skin at noon under a clear sky; clouds lengthen the time, water, sand and snow shorten it. Sunscreen extends the time only partly.
Monthly values: clear-sky noon estimate from the sun's angle, ozone and altitude. UV today: Open-Meteo forecast.
Wind & clouds
Wind and clouds in Karuizawa
How breezy and how cloudy Karuizawa is through the year. Tap a month to select it on the whole page.
Wind
Typical daily peak of the wind in km/h: what the afternoon breeze usually reaches, not the gusts.
In October, the wind in Karuizawa typically peaks at 9 km/h during the day: Beaufort 2, light breeze or less.
Clouds
Average share of the sky covered by cloud, day and night.
In October, cloud covers on average 68 % of the sky over Karuizawa: mostly cloudy, with about 4.7 hours of sunshine a day.
Wind: mean daily maximum of the hourly wind 10 m above ground (ERA5, 1996–2025). Gusts are stronger, and the model grid of about 28 km smooths out local effects such as capes and valley winds. Clouds: mean total cloud cover of all layers over day and night (ERA5, 1996–2025). Thin high cloud counts as cover even when the sun still shines through.
Heat & humidity
Heat and humidity in Karuizawa
How often the day gets hot in Karuizawa (30 °C and more), and in which months heat and humidity come together. Tap a month to select it.
Heat calendar
- pleasant
- some hot or muggy days
- often muggy
- often hot
- hot and muggy
In October, Karuizawa has about 0 hot days, with an average daytime high of 18 °C: pleasant. Heat plays no part this month.
Hot days reach at least 30 °C; a month counts as muggy when the mean dew point reaches 18 °C on at least 15 days. Averages from ERA5 and ERA5-Land, 1996–2025. Muggy nights through the year
Snow
Snow in Karuizawa
When Karuizawa is likely to be white: the chance of seeing snow during a week's stay, the days with fresh snow and how much falls. Tap a month to select it.
Snow calendar
- hardly any
- possible
- likely
- very likely
In October, it hardly ever snows in Karuizawa.
Snow days bring at least 1 cm of fresh snow. Fresh snow comes from ERA5 snowfall (1996–2025) at the height of the place, not on the slopes above it; the snow chance also weighs whether the snow settles. An estimate from climate averages, not a snow report.
Planning a trip to Karuizawa
Weather for your travel dates
Pick your arrival and length of stay, and we sum up the weather to expect.
Karuizawa in the school holidays
How the weather suits the usual holiday periods. Dates vary by school and region, so each holiday uses the months it usually falls in.
Karuizawa has its best school-holiday weather during October half-term (score 68) and its weakest during the Christmas holidays (score 16).
- 49
Easter holidays
Mar – Apr
Fair
- 14 °C by day
- 6.4 h of sun a day
- 14 rainy days a month
Keep in mind: Frequent rain, Snow
- 67
May half-term
May – Jun
Good
- 21 °C by day
- 6.3 h of sun a day
- 15 rainy days a month
- 52
Summer holidays
Jul – Aug
Fair
- 28 °C by day
- 5.5 h of sun a day
- 21 rainy days a month
Keep in mind: Frequent rain, Storm season
- 68
October half-term
Oct
GoodBest holidays
- 18 °C by day
- 4.7 h of sun a day
- 12 rainy days a month
Keep in mind: Storm season
- 16
Christmas holidays
Dec – Jan
Poor
- 5 °C by day
- 5.1 h of sun a day
- 14 rainy days a month
Keep in mind: Frequent rain, Snow
Based on the climate averages 1996–2025.
Getting there
Flying from
- Nonstop flight
- about 11 h 55 min
- Distance
- 9,470 km
- Time zone
- UTC+9
- Jet lag
- About 8 days (8 h east)
Rule of thumb for flying east: for a few days before, go to bed and get up a little earlier, and get plenty of morning light at your destination.
Most routes need a change of planes, which adds time.
Estimated from the straight-line distance: 30 minutes for take-off and landing plus 830 km/h cruising speed.
Good to know: Japan
- Currency
- Japanese Yen (JPY)
- Language
- Japanese
- Sockets
- Type A, B · 100 V
- Traffic
- Drives on the left
- Dialling code
- +81
UK plugs need a travel adapter
Only 100 V: chargers marked 100–240 V work, other devices need a voltage converter.
Sources: GeoNames (CC BY 4.0) and Wikidata (CC0). Please check details before you travel.
Storm season
Karuizawa lies in an area that Pacific typhoons can reach. The typhoon season runs from June to November, with most storms from August to October. A direct hit on any one place is rare, but if you travel then, keep an eye on weather warnings and book flexibly.
- January
- February
- March
- April
- May
- June: Season
- July: Season
- August: Peak
- September: Peak
- October: Peak
- November: Season
- December
Official season dates of the regional warning centres (NOAA, JMA, IMD, Météo-France, BoM, Fiji Meteorological Service); not a forecast.
Compare & alternatives
Compare with another place
Karuizawa compared
Put Karuizawa side by side with another destination.
Karuizawa vs Takasaki
In October the holiday weather in Karuizawa and Takasaki is about equally good (score 68 vs 68). During the day Takasaki is 4 °C warmer than Karuizawa.
| in October | Karuizawa | Takasaki |
|---|---|---|
| Holiday weather score | 68 | 68 |
| Daytime high | 18° | 22° |
| Sunshine | 5 h | 5 h |
| Rainy days | 12 | 13 |
| Best time | Apr – May, Sep – Oct | Apr – May, Oct – Nov |
Through the year
Best places in the country
Japan in October: the best places
In October, Karuizawa ranks 1 among the 31 nearest destinations in this country.
- KaruizawaThis page18°68
- 2Takasaki22°68
- 3Maebashi22°68
- 4Sano22°68
- 5Kawagoe22°67
- 6Tokyo22°22°65
- 7Minato22°22°65
- 8Fuji23°23°65
Places nearby
Near Karuizawa
Other destinations close by.
Places with a similar climate
Places with a climate like Karuizawa
Destinations whose weather through the year is closest to Karuizawa's – good alternatives.
Frequently asked questions about Karuizawa
When is the best time to visit Karuizawa?
The best time to visit Karuizawa is from April to May and from September to October. That is when the holiday weather score, which combines temperature, sea, sunshine and rain, is highest.
What is the warmest month in Karuizawa?
August is the warmest month, with average highs of 28 °C and nights around 19 °C. January is the coolest month at 3 °C.
When does it rain most in Karuizawa?
Rain is frequent from June to August and from December to March; the wettest month is July with 213 mm. The driest month is December with 69 mm.
How many hours of sunshine does Karuizawa get?
Karuizawa gets around 1,960 hours of sunshine a year. The sunniest month is May with 6.6 hours a day; in September there are 4.5 hours a day.
What time zone is Karuizawa in?
Karuizawa is on UTC+9 all year.
How long is the flight from London to Karuizawa?
A nonstop flight from London to Karuizawa takes about 11 h 55 min, for a straight-line distance of about 9,470 km. Most routes need a change of planes, which adds time.
When is typhoon season in Karuizawa?
Karuizawa lies in an area that Pacific typhoons can reach. The typhoon season runs from June to November, with most storms from August to October. A direct hit on any one place is rare, but if you travel then, keep an eye on weather warnings and book flexibly.
Which school holidays are best for Karuizawa?
Karuizawa has its best school-holiday weather during October half-term (score 68) and its weakest during the Christmas holidays (score 16). Holiday ratings (0–100): Easter holidays 49, May half-term 67, summer holidays 52, October half-term 68, Christmas holidays 16.