Japan will be under the influence of a spring weather pattern this coming weekend leading to above average temperatures and heavy rainfall by the end of the weekend.
The culprit for this incoming burst of warmth is a large ridge in the jet stream combined with strong southerly winds flowing in from the tropics. All this warm is also helping to fuel a storm system rolling in out of Eastern China and by Saturday night it will start to bring rainfall for the Korean Penisula and Western Japan.
Heading in to Sunday the low will gradually work east across central and Northern Japan.
For skiers and snowboards it is a sad case of enough moisture but to much warm air. If temperatures were colder with this low we would see a massive amount of snowfall. BUT, it looks like it will be warm enough to have a decent impact on the snow pack in lower elevations.
Further more the change in temperature following the heavy snowfall earlier this week will lead to a avalanche threat. The higher threat areas being off piste on steeper slopes. Those should pretty much just be avoided this weekend.
By Monday the rain should start to taper off in to the afternoon hours leaving above average temperatures and clearning skies through mid-week for most of Japan. If you enjoy the spring weather you will be extremely happy. Good news is despite the warm temps the snow pack is still in place so do not think the ski season is over with just yet.
Do also note with winds coming in from the west behind the weekends low the air quality will drop as yellow sand moves in to the picture.