But if blue = rain, white = snow, what does dark grey, light grey, light orange and dark orange mean? It looks more like precipitation chart, since it will be a cold NW wind.. e.g. Blue = most, dark orange meaning least.
Strictly speaking, Hikage is 95m higher than the "base level", which is 565m at Karasawa. It's nice that is snowing at Hikage though!!!!
Looks like the perfect winter setup, with all that "lake effect" cloud streaming off the Sea of Japan.
A couple of cm for Central Honshu for the next 7 days, a heap of snow for Hokkaido. (GFS) More on EC...
Standard in the 'fringe' seasons up there. Last year while it was lean pickings for many of the usual snow magnets further south, it was house burials as per normal up in the North West Diamond.
Every year I have been here, except last year, it has dumped on 1st December. So definitely unconcerned until it gets past that date and there is no snow. The small fall the other day was unusually early.
IMO Looks more like hoar frost rather an a dusting of snow as there's no drift accumulation in trees etc. More precisely there is an overly defined line of frost which leads me to believe it's dew point rather than freeze line halfway up that hill.
I had not really thought about and had assumed it was snow. Earlier that day, when I was outside there were snow flakes floating around but they melted when they settled where I was. I had assumed they had settled and not melted higher up the mountain. This was not there when I arrived that morning but was there later in the afternoon. And it was raining earlier. So not from overnight temperature drop. To be honest I was a bit surprised when I saw this at just after 4pm.
I reckon there is a good chance of snow in Nozawa and surrounds from the 23rd onwards, off and on through to 2nd. Freezing level down to 600 on the 23rd, winds look right for lake effect but not a strong one. Then staying cold for the following few days with the freezing level possibly staying down as the lows sweep through. A possible change to winter perhaps, but still way out in the models. Maybe that 26th opening will happen???
"Lows sweeping through" do not keep freezing levels down... They introduce warm air from the south on the eastern flank. The best scenario, particularly for central Japan, is to have no low pressure troughs all winter. The full winter change doesn't happen until we get long persisting high pressure over Siberia (>1040hPa)
Ahh but that is not what I said. The freezing level looks to be is staying down lower, despite some smaller lows sweeping through. The warm air did not look to be pushing the ridge of freezing back up north, so.... it might snow. You are quite right about the highs, not there yet.
Can see big highs over Siberia and Mongolia on the JMA forecast, 1045hPa 1056hPa, 1055hPa. And once it comes across the Sea of Japan where it picks up moisture, it snows! I would think lows have tropical influences unlike massive highs, that might make it warmer?
Highs don't move across the Sea of Japan and pick up moisture.The huge highs need to be further to the northeast, and, rotating clockwise, direct a northerly across Japan on the eastern flank, which picks up moisture. Deep lows rotate anticlockwise, dragging warm from the south on the eastern flank. See here: https://www.ski.com.au/xf/threads/weather-tutorial-for-japan.63512/
Looking at JMA... after a few days of warmth, there is some cold weather setting in from early next week in Hokkaido & mid next week for Honshu They are predicting a top temp in Tokyo next Thursday of just 11..
It's variable right now... it only got to 11.8 last Tue or Wed in Tokyo, so it's not necessarily an indication that winter is just around the corner.
Looks like winter may well be settling in for Hokkaido next week. Those predicted daytime temp's for Asahikawa are -4 & -5 next Wed/Thurs...
Yeah, that's looking a lot better. In really good season, full winter can start in Hoikkaido as early as late November. On rare occasions, central Japan can go early winter mode as early as the end of the first 7 days in December.