Karuizawa 7-Day Snow Forecast

Karuizawa Long-Range Snow Forecast Updated today

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Updated 11 August 2026 14:43 PDT

Long-Range Snow Forecast for Karuizawa

Long-range (14 to 45 days) from 12 August.

For Forecast detail, see below.

Karuizawa Snow Forecast Highlights

When will there be fresh snow in Karuizawa?

Karuizawa Snow Forecast Highlights - JMA
Snowfall prediction at mid-mountain (3,437ft)
Next Snow?
There is no snow currently in the forecast for Karuizawa.

Long-range Snow Outlook for Karuizawa

Snowfall

Snow Line

Max 84°F
Min 58°F

Snow unlikely

Karuizawa Long-Range (2 weeks+) Snow Forecast Outlook

Note :- Mountain weather is extremely dynamic; the forecast below will change. Any forecast snow may move forward or back in the forecast, and predicted snowfall depths will be revised in subsequent updates.

16 Day Weather and Snow Forecast for Karuizawa from OpenMeteo(JMA)
	Snow and Weather	Temp Town
Wed 12	Rain.	Max 66°F Min 63°F
Thu 13	Light rain.	Max 69°F Min 65°F
Fri 14	Light rain.	Max 69°F Min 66°F
Sat 15	Light drizzle.	Max 68°F Min 63°F
Sun 16	Light drizzle.	Max 76°F Min 59°F
Mon 17	Clear sky.	Max 84°F Min 58°F
Tue 18	Clear spells.	Max 81°F Min 64°F

No significant snowfall is forecast for this period.

This Snow Forecast for Karuizawa, Japan gives the predicted Snowfall and Freezing Levels for the next week.

The forecast snowfall depths given are the likely average accumulations for the Lower and Upper slopes. The actual snow depth in Karuizawa, on any given trail or itinerary, may be dramatically different, particularly if the snowfall is accompanied by high winds and/or varying air temperatures.

Snow Forecasts beyond two days ahead are subject to significant change and variable reliability.

Karuizawa Snow Forecast updated at 14:43 PDT, next update expected imminently.

Ensemble forecast for Karuizawa, Japan at 3,084ft

Daily Mean Temperature (yellow line is control)

Daily Total Precipitation (blue line is control)

What are Forecast Ensembles ? Multiple forecasts from running the same weather model with slightly different inputs. The prominent line (the 'control') is the model output from standard inputs, the thinner lines are the variations. Plotted together, they show a range of possible outcomes; the closer they are, the higher the confidence.

How to read Long Range Ensemble Forecasts

These forecasts are from ECMWF EC46, a long-range, low-resolution (area) model. They may not accurately reflect local conditions and should be read as area forecasts, indicating whether the coming weeks are likely to be warmer, colder, wetter, or drier than average.

What to look for?

Temperatures trending downward at the same time as precipitation spikes upward... means snow!

Lines close together indicate a high confidence, while wider spreads signal uncertainty.

Snow Reliability

Karuizawa typically enjoys reliable snow conditions with an average snow depth of 100 cm during peak season. For the latest snow information, including current conditions and snowfall, check J2Ski for updates.

Off-Piste Safety in Karuizawa

Before skiing or snowboarding off-piste in Karuizawa, you must assess the local snow conditions. Always check the local Avalanche Risk Level and ski with appropriate safety equipment.