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Japanese Super Hot and Humid Summer 2020 thread

Discussion in 'Daily & Chat' started by Asama, Jun 29, 2020.

  1. Asama

    Asama Addicted

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    Disclaimer: Not my thread title idea!

    2020 so far for me: warmest ever winter → so-so spring → hot summer???

    Stealing the JMA stats from Karuizawa observatory which is the closest and probably most relevant "proper" observatory to me...

    Monthly average temperatures:


    So far every month except April (which was randomly quite cold) has made the top 10 warmest for the respective month. Records go back to 1925 for this location, so just shy of 100 years...

    Jan: warmest ever (beating previous record by 0.5C)
    Feb: 3rd warmest
    Mar: 4th warmest
    Apr: Actually not warm!!
    May: 8th warmest
    Jun: currently 3rd warmest - may end up 2nd depending on how today and tomorrow pan out...

    The JMA long range forecast is for the warm trend to continue... would love to see a return to "normal" temperatures, ie months not in the top 10th percentile! The trend seems pretty clear though :'(

    Nights in particular have struggled to cool down - here are June's temperatures against the 30 year average. You can see it barely dips below average all month:


    Also look at the plot for the last 8(?) years for july... daily lows consistently sticking above average. Not sure what has fundamentally changed to create this effect - maybe higher humidity than in the past?

    On a positive note, over the last week the rainy season has retreated a couple of times to give lovely spring-like days with cool (even chilly) evenings and early mornings. Making the most of them before summer proper kicks in.

    *I'm not a weather expert in any way, shape, or form, although I would like to be... just addicted to the stats.
    Here's where I get them: JMA site
    http://www.data.jma.go.jp/obd/stats...hp?prec_no=&block_no=&year=&month=&day=&view=

    That whole site is a treasure trove... don't know if any other countries publish their data so generously??
     
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  2. Ramenman

    Ramenman One of Us Ski Pass: Gold

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    It's a weird "farming season" for me so far. April was cold, it was nearly 2 C colder in our farm. And it was rainy too. Cold rain killed a lot of young summer vegetables at our garden / mini-farm. May was nicely warm (significantly warmer than average May). June is also warmer and it's super rainy too. Yes, I know it's rainy season now, but rainning on 6 days out of 7 days (= a week) is a bit too much. Japan's abundant rain is "basically" good for farming but this month's too frequent rain is a bit too much. It's actually making our vegetables and fruits a bit sick. As you said, this May and June are (were) warmer / hotter, but hot May and June are okay in that they are just "early summer" and they are actually not that hot. Hot July and August, I'm very scared of them:eek: and I envy you because you are living in a village of 1,000m asl;)
     
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  3. Asama

    Asama Addicted

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    I remember last year (2019) rainy season being extremely wet with barely any let-up, so this year feels OK in comparison, even though it's obviously been raining a lot. I haven't really looked to see how it compares to the average. I think our local geography gives us a lot of precipitation (maybe orographic lift as clouds move over from the west and south are pushed over the Asama chain?) so if it's going to rain anywhere, we get some here.

    PS although nothing to do with summer, in winter we catch the very edge of the lake effect snow when the wind is in the right direction, but it normally doesn't persist all day. Often it is possible to look across the valley and see heavy snow falling around Kusatsu/Sugadaira direction whilst it is sunny here. Interesting how the specific mountains affect how rain/snow falls.
     
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  4. Ramenman

    Ramenman One of Us Ski Pass: Gold

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    This is from JMA. In a lot of weather stations, the last 30 days (between this May 30th and June 28th) were 2 C warmer / hotter than average year. The image below is automatically updated everyday, so if you see it tomorrow the data will be between May 31th and June 29th.
    [​IMG]
     
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  5. Ramenman

    Ramenman One of Us Ski Pass: Gold

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    In Kanto region (Kanto = Tokyo area), the rainy season started about 20 days ago (around June 10th). This is the precipitation comparison of the past 20 days (between June 9th and 28th). As you can see, a lot of weather stations have had 150 - 200% precipitation (or even more) compared to average year. This data is also automatically updated everyday (and if you see it tomorrow, it'll be between June 10th and June 29th). It's a nicely sunny day here today, but it had been raining 8 or 9 out of 10 days or so till yesterday.
    [​IMG]
     
  6. Asama

    Asama Addicted

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    I haven't seen those charts before, would you mind sharing the link where I can find them? And is it possible to show them for historical periods? That would be amazing...
     
  7. Billy_Buttons

    Billy_Buttons Que Sera, Sera Ski Pass: Gold

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  8. Ramenman

    Ramenman One of Us Ski Pass: Gold

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    You can see it here(You can compare the last 5 days, 10 days, 20 days, 30 days, 60 days and 90 days with average year).
    https://www.data.jma.go.jp/obd/stats/data/mdrr/tenkou/indexTenkouTem5dhi.html

    If you click "地点別データ一覧表", you can see more detailed data of each weather station.

    Not only that, JMA make all historical data available. For example, the website of JMA tells you how the weather was when your wife was born(You only need to choose the nearest weather station, date, etc).
    https://www.data.jma.go.jp/obd/stats/etrn/index.php

    According to JMA's data, Karuizawa has had a lot more hot days in the past(the highest temperature of Karuizawa of June was recorded in 1987, and 8 out of 10 hottest days of June were recorded before 2010 and one of them was 1936!). You can see it here.
    https://www.data.jma.go.jp/obd/stat...=48&block_no=47622&year=&month=6&day=&view=h0
     
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  9. Asama

    Asama Addicted

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    Thanks for that. Yes, I love the JMA site...
    Not just weather, but also earthquake and volcano data, etc etc.
    But the searchable weather history in particular is amazing. Have spent many hours of my life on there.
    Seems very generous to provide this as a free service to the public, actually.
    The UK just offers a miserable selection of monthly data in a format that is hard to read. If you want more than that, they make you pay for it... don't know about other countries.


    Yes, but outliers are less indicative of a trend than the averages (I'm not a mathematician but I know that much!) That's why I'm interested in the monthly averages.
    This month hasn't had any especially hot days (sort moderately hot at the beginning), but still going to be 2nd/3rd warmest on record. My guess is that the lows not getting down to what they "should" be is contributing a lot to pushing up the averages.

    Interestingly (is it? to me at least), this seems to happen a lot more consistently in the summer months when the humidity is high:


    Compare to the winter months where the temp seems to jump around a lot more and shows less of a trend (ignoring the line for the appalling 2019-2020 winter)


    If any weather experts have a theory to explain this, would be interested to hear.
     

    Attached Files:

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  10. Asama

    Asama Addicted

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    Surprise surprise!
    JMA says July gonna be hot as well

     
  11. Ramenman

    Ramenman One of Us Ski Pass: Gold

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    Your village's cabbage farmers might earn a lot due to a hotter summer. Cabbages don't grow (they get sick) in hot & humid climate and hotter summer = cabbages become expensive (your place is cooler than most other Japanese cities;))
     
  12. Asama

    Asama Addicted

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    Yeah, fingers crossed it will be a good year for them. Think there have been problems due to lack of wholesale demand for vegetables (downturn in catering industry). A farmer I know says he was making a loss on lettuce so was forced to plough tens of thousands of lettuces back into the ground. Seems every year there there is some new disaster for farming :p

    Weather is good = wholesale price goes down.
    Weather is bad = crops destroyed and nothing to sell.
    and sometimes, they get lucky (i.e somewhere else's crops get destroyed and price goes up!)

    Seems an unsteady life!
     
  13. Ramenman

    Ramenman One of Us Ski Pass: Gold

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    It seems some rivers are flooding now. In Japan, mountains are very close to the oceans, which means, rivers tend to be steep. Steep narrow winding rivers + big precipitation = Japan is very flood prone.
    [​IMG]
    [​IMG]

    This explain how steep Japanese rivers are. All of the left most rivers are Japanese rivers.
    [​IMG]
     
    #13 Ramenman, Jul 4, 2020
    Last edited: Jul 4, 2020
  14. Ramenman

    Ramenman One of Us Ski Pass: Gold

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  15. David-eTO

    David-eTO Early Days

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    If you don't mind me asking, how will the rainy season impact on the coming winter?
     
  16. Ramenman

    Ramenman One of Us Ski Pass: Gold

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    I think you should ask weather experts such as @Sandy-san about it, not me:rolleyes:. I assume summer weather won't affect the coming winter, though:)
     
  17. Ramenman

    Ramenman One of Us Ski Pass: Gold

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    Special flood warnings have been issued to some regions of Nagano and Gifu. It seems some rivers in Nagano and Gifu are flooding now. This rainy season is too rainy. Leaves of our fruits and vegetables have been always wet (because it has been raining everyday since 3 - 4 weeks ago) and it has made our vegetables and fruits sick:crap:
     
  18. PMG

    PMG One of Us Ski Pass: Gold

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    Kyushu is taking a hammering this summer - again.
     
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  19. Asama

    Asama Addicted

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    Yes, third summer in a row, or at least third out of the last four.
     
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  20. Asama

    Asama Addicted

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    As I understand it, there's no direct connection. Winter is more affected by strength of the siberian high (which starts developing from late summer), arctic oscillation, jet stream position, etc.
    Anecdotally I think the autumn weather often gives clues as to how winter will turn out, but sure meteorologists would disagree.
     
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  21. Ramenman

    Ramenman One of Us Ski Pass: Gold

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    Great!, we've got a new Tenki-sensei(Tenki = weather):cool:. You are Asama-sensei;).

    Come to think of it, I remember a heavy rain hit Tsumagoi, causing landslide last year. Why I remember it is because a road to a ski resort was closed due to the land slide. Do you remember it?. You are interested in geology?. I'm a bit interested in geology, so whenever I drive on a mountain road, I enjoy estimating the risk of landslide, flooding, etc:p
     
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  22. Asama

    Asama Addicted

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    Yes, we were hit badly by Typhoon 19 (along with many other places). The photo below is 国道406 (aka 144) between Ozasa and Tashiro. I took this pic in January 2020, 3 months after typhoon, and no sign of any repairs. Still not reopened and not sure when it will be.

    I think the landslide you remember may have been on the road to Kazawa snow area/Kyukamura? People were left stranded for several days at Kyukamura...



    PS, I don't claim to be a weather expert, I just find it very interesting (hence being on this forum at all, as a non-skier)
     
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  23. Ramenman

    Ramenman One of Us Ski Pass: Gold

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    Reportedly, 84 rivers have flooded and 179 landslides have been confirmed this week (as of this morning)
     
  24. fennekeg

    fennekeg One of Us Ski Pass: Silver

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    Hey, another non-skier! :wave: Hi :) I'm on here because just like a lot of others I like Japan in the snow. No skiing for me, but I do enjoy walking/hiking in the snow, with or without snowshoes.
     
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  25. Ramenman

    Ramenman One of Us Ski Pass: Gold

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    Asama-san is from Mt.Asama region as the name shows. Mt.Asama (2568m) might be a very good mountain for someone like you. A lot of Japanese mountains can be too snowy to walk in winter. At the same time, when warm days hit, it can rain, not snow on low altitude mountains even in winter. In my opinion, the best for you to hike on snow is, cold but "not too snowy". In that sense, Mt.Asama might be one of the best because Mt.Asama is less snowy if compared to major Japanese ski resort mountains but the altitude is higher, so the snow condition is stable (precipitation in winter always mean snow there). There are onsen Ryokans and hotels at about 2000m asl there (in and around Asama 2000 ski resort). 2000m asl = higher than the top lift stations of 99% Japanese ski resorts (most mountains are lower than 2000m, and even if they are higher than 2000m, they are too snowy to access to 2000m or higher). So, Mt.Asama is a rare mountain in that there are ryokans and hotels open in winter around 2000m asl.

    This is one of Onsen Ryokans around 2000m asl there.
    https://www.takamine-onsen-hitou.com/


     
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  26. fennekeg

    fennekeg One of Us Ski Pass: Silver

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    Oh that's good to know, thanks! Yes those are exactly the conditions I'm always on the lookout for :)
     
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  27. Asama

    Asama Addicted

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    Hello!:wave:
    Yes, I tell other people I prefer looking at the snow than playing in it, but it seems only skiers share my enthusiasm. Except for incomers like me the locals all seem to hate snow...

    Thanks for the promotion Ramenman! Yes, we're cold enough that when it snows, the snow stays for weeks (actually it freezes up into ice). There's a lot of variation from year to year, but every year since I moved here the biggest snows have been in the spring (March-April) when wet weather systems get bigger and more frequent. In Jan-Feb we tend to get a nice sprinkling a few times a week (when the wind is coming from the Sea of Japan) and one or two big dumps a month when a low passes by on the pacific side. So a bit different from the weather that feeds the big ski resorts.

    Personally I think Kusatsu onsen (very close to me) has a good balance. Bit snowier than here, reliably nice and cold. Also great onsen and decent tourist infrastructure ;)
     
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  28. Asama

    Asama Addicted

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    Back to the topic of the super hot and humid summer, the sun came out today! It was the nicest day in weeks, low humidity and high of about 22C.
    Back to daily rain from tomorrow... horrid weather, everything is getting mouldy. Rainy season this year has been pretty full on. And it's claimed a (allegedly) 1000 year old tree in Gifu:
    https://www3.nhk.or.jp/nhkworld/en/news/20200712_15/
     
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  29. Ramenman

    Ramenman One of Us Ski Pass: Gold

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    It might not be the rainiest rainy season for where I live, but older people (some of them are farmers) say this is "the least sunniest" rainy season for them. I haven't seen the sun at all recently. According to them, the worst summer was 1993(I'm a bit too young to know it). As you might know, Japanese people don't eat rice much now if compared to long time ago, and Japanese government have been saying to Japanese rice farmers "produce other vegetables or fruits instead of rice" since decades ago. Basically, rice was already oversupply in 1980s and Japan never needed to import rice. But, 1993's 冷夏 = cold summer was exceptional. Even Japan needed to import rice because of the notorious cold summer. This rainy season is just more cloudy or rainy. It's not cold, though(it's rather hotter).

    About cold summer 1993 :https://en.wikipedia.org/wiki/Rice_riots_of_1993
     
  30. Ramenman

    Ramenman One of Us Ski Pass: Gold

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  31. Asama

    Asama Addicted

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    I feel like something is lost in translation here... what would cause rain if not water vapour?

    Is it too much to hope that the Pacific high will remain weak and spare us an overly hot summer?
    Last couple of summers have lingered late into the year and the autumn weather systems have been slow to develop (Kanto has missed Kogarashi Ichigo two years in a row). In my mind that's because the Pacific high refuses to clear away.
    2018 was a nice cool autumn though :)

    Kogarashi ichigo: https://www.jitco.or.jp/webtomo/pdf/kogarashi_en.pdf
     
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  32. Sandy

    Sandy Dark Sith Lord of the Pool Room Moderator Ski Pass: Gold

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    Two years ago, the devastating floods in SW Honshu & Kyushu were due to the rainy season stationary front (Stationary boundary which had already moved north of SW Honshu), colliding with a weak typhoon (Prapiroon). The typhoon trapped and redirected the stationary boundary back to the south, where it remained stationary for about a week. I have weather maps somewhere from that period.
     
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  33. Ramenman

    Ramenman One of Us Ski Pass: Gold

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    By the way, overly hot summer can kill more people in Japan than COVID-19 can. A very good example is the comparison between 2009 and 2010. In 2009, "only" 249 people died of heatstroke in Japan while 1,731 people died of heatstroke in 2010. Tokyo's average daily high temperature of July - August - September of 2009 was 28.6 C and it was 31.4 C in 2010. So, 2010's July - August - September was nearly 3 degree C hotter than the previous year (2009).

    Here is 2009, look at the daily high temperature of 7~9, it's 28.6 C
    https://www.data.jma.go.jp/obd/stat...block_no=47662&year=2009&month=8&day=&view=p1

    Here is 2010, look at the daily high temperature of 7~9, it's 31.4 C
    https://www.data.jma.go.jp/obd/stat...block_no=47662&year=2010&month=8&day=&view=p1

    2.8 degree C hotter and 1,482 (=1,731 - 249) more people died of heatstroke. Recently, COVID-19 kill only 0 - 2 per day in Japan. So, overly hot summer can kill more people in Japan in July - August - September than COVID-19 can. I hope this summer is cooler:thumbs:!
     
    #33 Ramenman, Jul 15, 2020
    Last edited: Jul 15, 2020
  34. Sandy

    Sandy Dark Sith Lord of the Pool Room Moderator Ski Pass: Gold

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    While June was warmer than average, July is currently tracking a bit below average for maximum temperature. Last year, July was well below average.
    Also, so far as rainfall is concerned, here in Yokohama it's above average for the first 2 weeks of July. and is already above last year's July rainfall, and above the the previous two July totals combined.
    I've noticed that the number of rainy days for July is higher than other years. (the data shows that the number of sunshine hours in Yokohama is well below average, with only 30.4 hours in the first 2 weeks of July)
     
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  35. Sandy

    Sandy Dark Sith Lord of the Pool Room Moderator Ski Pass: Gold

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  36. Asama

    Asama Addicted

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    Similar story here, if anything the weather has been cooler than late may/early June. My nearest weather station in Tashiro has been hovering just under average for max (my home thermometer has unusually been giving slightly lower maximums than these most days, normally it is the opposite). As usual, minimums showing a solid above average trend (the recent dip was when the rainy front moved to the south for a day and the sun came out).

    I'm happy that it's cool, but it's dreary, dreary weather. It's like groundhog day.



    https://weather.time-j.net/Stations/Jp/Tashiro/7
     
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  37. Ramenman

    Ramenman One of Us Ski Pass: Gold

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    It's terrible, Ramenman farm needs more sunshine:mad:!
    [​IMG]
     
  38. Asama

    Asama Addicted

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    I have the rainy season blues...
    Apparently Okushiri is the best place to be in Japan right now!
     
  39. Ramenman

    Ramenman One of Us Ski Pass: Gold

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    Finally, a sunny day has come. It's the first sunny day of July 2020. Since this rainy season started about 40 days ago, I think it's the second or third sunny day. 2 or 3 sunny days out of 40 days, crazy! (it's the least sunniest rainy season and the worst rainy season for farmers)
     
  40. Ramenman

    Ramenman One of Us Ski Pass: Gold

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    It's mid summer now, but some people are still skiing:p (The video was filmed on Mt.Gassan, Yamagata Pref last weekend = July 18th).
     
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  41. Ramenman

    Ramenman One of Us Ski Pass: Gold

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    They say this season has been one of the most "typhoon-less" seasons so far. Only two typhoons have been formed (one in May and one in June). I'm not a weather expert, so I don't know what this means:p
     
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  42. Asama

    Asama Addicted

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    It seems we're on track to have the first typhoon-less July on record.
    Japan has still taken a battering from endless heavy rain though, so not much consolation really :'(

    Meteorologically speaking I don't know what it means either, although the fact that the pacific high has been stuck to the south of Japan so far this summer may be related. Not sure if the Pacific high is unusually weak, or just trapped in the wrong place?
     
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  43. Sandy

    Sandy Dark Sith Lord of the Pool Room Moderator Ski Pass: Gold

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    The fact that the meiyu front has been battering China with record rain, and Japan has had record low sunshine, and high levels of rain without typhoons, is indicative of highs south of the front.
    Or to put it another way, the strong meiyu front has been ensuring that the highs are staying reasonably stationary south of Japan, blocking typhoons.
    [​IMG]
     
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  44. Asama

    Asama Addicted

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    Thanks Sandy for the neat explanation. So in other words, it's more a case that this year's meiyu front is unusually strong, rather than the highs being unusually weak? My rudimentary understanding is that as Pacific High gathers strength, it pushes the meiyu front up and out of the way, but from what you write, it sounds like the strength of the front hasn't allowed the high to edge its way in so far this year?

    Can you see any particular variable that's contributing to the intensity of the meiyu front this year?
     
  45. Sandy

    Sandy Dark Sith Lord of the Pool Room Moderator Ski Pass: Gold

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    The meiyu front starts out new Taiwan around March and moves steadily north every year, pushing through Japan from early June in Kyushu pushing through northern Honshu before the end of July. It then dissipates due to northerly low pressure systems.
    I've never really looked at why it varies like it has this year, but a big driver can often be SST (Sea Surface Temperature) anomalies. Warmer SST tends to generate low pressure, while cooler tends to be conducive to high pressure.
    Here's June:
    [​IMG]
    There's a few things to note about this. Sea of Japan is well above average, as is the area off China, SW of Korea.
    That finger of blue pushing across the Pacific from South America, is indicative to a possible La Nina, but it can also disrupt Typhoon formation in the central/western Pacific.

    Compare with June last year:
    [​IMG]
     
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  46. Ramenman

    Ramenman One of Us Ski Pass: Gold

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  47. Ramenman

    Ramenman One of Us Ski Pass: Gold

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    I know long term forecast is not reliable. JMA release 3 month and 1 month forecast as long term forecasts. Farmers are supposed to count on the long term forecasts, but JMA didn't say this rainy season would become this rainy (and cooler). Here is their newest one month forecast. They say Kanto region is likely to be cooler. I hope it's actually cooler!. Even with the newest super computer, it's very hard to forecast. I wonder if 1 - 3 month forecast will be reliable in 2030 with the new super computer.
    [​IMG]
     
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  48. Asama

    Asama Addicted

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    Yes, they got it completely wrong, but I'm not complaining! Not about the temperature at least.
    Wouldn't mind a bit of sunshine (remember what that is?) in August, but if temperatures are going to stay below average I'm all for it.
     
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  49. Ramenman

    Ramenman One of Us Ski Pass: Gold

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    I'm not complaining either. JMA are one of the best weather expert groups in the world and it's simply long-term weather forecast is still a bit too complicated and difficult for humanbeing as of 2020.

    I'm afraid mid - late August can be super hot. I mean, JMA's one month forecast is hugely dependent on the first one - two weeks. So, this long rainy season might make the average temperature low between this week and early August, but super hot summer (= even hotter than average sumer) might come after the rainy season unfortunately!
     
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  50. Asama

    Asama Addicted

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    It's possible, but at least it would be short. The hottest weather can't maintain its intensity beyond the first week or two of September, so at worst we could have maybe one month of super hot weather this year? In 2018 the super hot summer started at the end of June (tsuyu ended on June 29th in Kanto) and it stayed hot until the end of August, so the midsummer weather lasted for about 8 weeks.
     
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