Hello all, welcome to another Japan on the long term update. We are in the middle of peak season, so I am going to look out towards the end of the peak season. We will look into the models and the drivers as well, reviewing the whole weather system around Japan.
EC Monthly shows a system coming over Honshu late on the 6th, with heavy snow for Hokkaido, and a snow/rain mix for Central Honshu. NW winds beginning on the 7th, bringing moderate-heavy snow for Honshu and Hokkaido, until later on the 9th. Long range GFS shows light snow showers over this period for the Japanese Alps.
EC Monthly shows NW-W winds developing over Northern Honshu and Hokkaido on the 11th, bringing moderate snowfall to these areas. The system clears early on the 12th. CFS shows moderate-heavy snowfall for Honshu and Hokkaido during this period, particularly the 12th.
EC Monthly shows a low coming over Central Honshu, bringing moderate-heavy snowfall at times over the 13th and 14th period, albeit a little warmer than lake/sea effect wind systems. CFS shows more moderate snowfall on the 14th, but shows weakening winds on the 15th, stopping most of the snowfall.
EC Monthly shows a huge low approaching Japan. On the 15th, rain(snow up high) affects Northern and Central Honshu. On the 16th and 17th, the low brings very heavy snow to Hokkaido, and brings NW winds to rake the Honshu Coast, with moderate-heavy snowfall for the ranges. By the 18th and early on the 19th, the snowfall in Hokkaido has weakened and so has the NW winds bringing snow to Honshu. The system fades away early on the 19th, but another low looks to come over towards Japan for the next couple of days, looking a little colder, than the previous low. CFS shows the 15-17th, as the best period for NW winds, bringing moderate snowfall to Honshu and Hokkaido. The 18th and 19th brings lows to the south, but they won’t bring much rain (or snow).
MJO is currently in Phase 4, and is expected to maintain it’s orbit into Phases 5,6&7, as shown by this collection of MJO forecasts from TIGGE. The most important EC, shows a movement to Phase 7, which correlates with more snowfall for the Japanese Alps.
The Stratospheric Polar Vortex is forecast(by EC) to strengthen, and then develop a weakening in the Day 6-10 period. This could signal a -AO tendency, which favours Japanese Alps snowfall. EPS Control continues this trend into the Day 10-15 period.
EC Monthly forecasts the AO to be negative in the medium term, however it neutralises in line with other factors by Mid February. A negative AO favours Japanese Alps snowfall. CFS shows a -AO, until Mid March however, which is potentially good news.
So the AO looks negative in the medium term, and neutral in the longer term, thanks to the Strat and other factors. MJO looks good, so there is plenty to smile about if you are skiing in Japan in February.
Thanks so much for reading. I hoped you enjoyed reading it.
Disclaimer: There is low skill asssociated with using long range model forecasts to find snow systems. All systems you see here will change, as the date gets closer and may not eventuate all together. I don’t give much accuracy to these forecasts, but you can give these a bit of your time and your dreams might come true 😉 I find the chase of these long range snow systems awesome, so come and join me! The climate driver forecasts tend to have a bit more skill than the model forecasts, but certainly don’t put all your money on them. However, climate drivers are an awesome tool to explain the weather around us.
Thanks again for reading this Japanese long range snow forecast, follow me on Twitter @longrangesnow and subscribe to my email list by clicking on the tab on the main header above.