Japanese Super Hot and Humid Summer 2020 thread

Ramenman

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End of rainy season has been announced for Northern Kyushu, Shikoku, Chugoku regions.
The end is in sight!

I think I heard a TV weather forecaster saying Kanto = August 3rd. As far as I remember, it's the longest rainy season and the worst farming season!

The worst ski season (the least snowiest season) - COVID-19 - the worst farming season (caused by the least sunniest summer). 2020 is very cursed!
 

Sandy

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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.
temp-00.png

This is why I never take any notice of the JMA long term forecasts.
I mean, look at it... It says:
Kanto:
- 50% above normal
- 30% normal
- 20% below normal

But you can also read it as:
- 50% above normal
- 50% normal or below normal
Which means nothing.

What it's been Tokyo:

Normal (last 10 years):
- Max temperature: 30.8 C
- Precipitation: 105.8 mm
- Sunshine: 170.5 hours

This July:
- Max temperature: 27.7C
- Precipitation: 269.5 mm
- Sunshine: 44.5 hours


Yokohama (where I live):

Normal (last 10 years):
- Max temperature: 30.2 C
- Precipitation: 138.6 mm
- Sunshine: 195.9 hours

This July:
- Max temperature: 27.6C
- Precipitation: 377.5 mm
- Sunshine: 59.7 hours
 
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Ramenman

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The weather station of JMA in the city where we own a mini farm shows it's only July 19th that had sunshine hours longer than 4 hours per day this month. In all the other days, sunshine hours were less than 4 hours per day. It's very likely July of 2020 is going to be the shortest sunshine hour month in history (the current record is July of 1988).

The 4th least sunniest month in history is about 40 hours per month. This month, it's only 20 hours as of 30th. Scary, even compared to 4th least sunniest month, it's only half!.
sun30dhi00.png

indexTenkouSun30dhi.html
 

Sandy

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For those who can't read Japanese (probably 99% here :p ) :
Due to the bad weather caused by the rainy season, the sunshine hours in July were only 37% in eastern Japan and 49% in western Japan. Although it is a provisional value until 30th, it is the shortest in July since the start of statistics in 1946. Cost of living was affected by rising vegetable prices.
July precipitation reached 232% (provisional value), which was more than twice the normal value in both East and West Japan, and was the highest in the history of statistics. Even if the data for 31 days is reflected, the conclusion looks certain.
According to the Japan Meteorological Agency, sunshine hours were 37% on the Japan Sea side of eastern Japan and 38% on the Pacific side. The Sea of Japan side of western Japan was 45% and the Pacific side was 51%.
 
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Asama

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But in better news, the end of rainy season was announced for the Kanto region (Tokyo) today.
3rd latest on record I believe.

The weather was great here (northern Gunma pref) today. I wouldn't mind a month of days like this... it would go some way to making up for the solid month of rain we've just had.
 

Ramenman

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But in better news, the end of rainy season was announced for the Kanto region (Tokyo) today.
3rd latest on record I believe.

The weather was great here (northern Gunma pref) today. I wouldn't mind a month of days like this... it would go some way to making up for the solid month of rain we've just had.
Asama-san, it seems you gave this thread a wrong title;)
 

Ramenman

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You mean to tell me that australian skiers aren't interested in day to day weather in Japan!!? Shocked!

but yes, 読み書きOK.

Haha, it's a ski forum, so majority people here are not interested in summer, especially summer abroad:p. Plus, this season, people on this forum are busy chatting about COVID-19;). But seriously, people like Asama-san will make this forum even better. I mean, it's already the world's best ski forum. And now, it has become the world's best COVID-19 forum. Non-skiers like Asama-san joining this forum makes this forum even more nicely diverse. I think this forum (ski.com.au) is already a very good "weather forum", and Asama-san can help this forum become "the world's best weather forum" in the future:thumbs:
 
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Asama

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I think this forum (ski.com.au) is already a very good "weather forum", and Asama-san can help this forum become "the world's best weather forum" in the future:thumbs:

I think this forum assimilated a weather forum at some point in the past?
I'm much more of a weather watcher than a weather expert, so not much to contribute.
But yes, a (reasonably) friendly forum, which is why I'm still here even though the snow's melted.
 

Ramenman

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And @Ramenman you've just put a jinx on August!!!!! :p ;)

Next 7 days forecast for Tokyo: 31,30,31,32,32,33,33

Haha, seen from Ibaraki - Fukushima - Yamagata, 30 - 33 is very hot, but seen from Tokyo, 30 - 33 is "just hot", not "super hot", I'd say;).
 
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mannyk

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Haha, it's a ski forum, so majority people here are not interested in summer, especially summer abroad:p. Plus, this season, people on this forum are busy chatting about COVID-19;). But seriously, people like Asama-san will make this forum even better. I mean, it's already the world's best ski forum. And now, it has become the world's best COVID-19 forum. Non-skiers like Asama-san joining this forum makes this forum even more nicely diverse. I think this forum (ski.com.au) is already a very good "weather forum", and Asama-san can help this forum become "the world's best weather forum" in the future:thumbs:
Im interested..some time in the future we would love to visit, perhaps spring or Autumn, I grew up in Tropical Darwin so not really interested in the humidity in summer.
 
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Asama

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Im interested..some time in the future we would love to visit, perhaps spring or Autumn, I grew up in Tropical Darwin so not really interested in the humidity in summer.

Wow, the Darwin climate looks like hell to me!
Either hot and wet... or hot and dry.

Looks like it only rarely drops below 20C?
 

mannyk

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Wow, the Darwin climate looks like hell to me!
Either hot and wet... or hot and dry.

Looks like it only rarely drops below 20C?
Its only free of humidity for 4 6 weeks of the year, they just had a cool blast a week ago. Inland down to single figures and about 16in town.. Ugg boots come out:)
 
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mannyk

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Wow, the Darwin climate looks like hell to me!
Either hot and wet... or hot and dry.

Looks like it only rarely drops below 20C?
Ive gone fishing early 0200 and it was 29 at the service station, sweating while you fill up and get ice..for the beers..:thumbs:
 
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Asama

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Just enjoyed the first "guerilla downpour" of the summer.
Chucked it down like crazy for 10 minutes, then stopped like someone turned off a tap and the sun's back out...
Temp has dropped by 3 degrees in about 30 mins, so nice and fresh too.
 

Asama

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Hamamatsu city matched Japan's highest ever recorded temperature with 41.1℃ today.

Normally we get frequent afternoon downpours in the summer, but this year it's only rained properly once in the last two weeks. After the 6 weeks of constant rain of June-July I'm not complaining about the sunshine, but the weather seems unusually stable over the mountains. I believe Tokyo has been hit by heavy thunderstorms a couple of times though.
 

Ramenman

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It's the worst farming season!. One of the driest August has come after the least sunniest June and July. The precipitation of the last 10 days is only 20 - 30% of average season. Early August = the hottest period of a year, and hottest means without precipitation farmlands tend to dry up!
 

Sandy

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Local media are reporting heatstroke killed 103 people in Tokyo this month (as of 18th) and COVID-19 killed 9 people in Tokyo this month (as of 18th), so it seems heatstroke is a 11+ times bigger devil for people in Tokyo at the moment:eek:

Source : https://news.yahoo.co.jp/articles/72168d43c658736ad92e7ae528bf9f77d5e22ff7
That's not correct!!
On 31st July, deaths from COVID in Japan was 1006, and as of 18th Aug, it was 1135 (+129). Tokyo seems to have around 1/3 of the COVID deaths in Japan, so it's likely to be around +40 to +45 for Tokyo, not +9. However, heatstroke number are still higher....
 

Ramenman

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That's not correct!!
On 31st July, deaths from COVID in Japan was 1006, and as of 18th Aug, it was 1135 (+129). Tokyo seems to have around 1/3 of the COVID deaths in Japan, so it's likely to be around +40 to +45 for Tokyo, not +9. However, heatstroke number are still higher....

It's actually only 9 as of 18th. I mean, clusters haven't been happening inside hospitals, aged care homes, etc "in Tokyo" during the second wave, but happening in Osaka, Okinawa, etc. When it comes to Tokyo, not many people have died of COVID-19 this month = August. That's why I keep saying the number of deaths depends on who is catching the virus. Tokyo have by far the biggest number of new cases last month - this month, but not many people have died because high risk people have been protected during the second wave.

Here is the data (source). You can see how many people have died in Tokyo this month.
https://toyokeizai.net/sp/visual/tko/covid19/

Ah, this conversation should be in "COVID-19 in Japan" thread:p?
 

Asama

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This stable weather just goes on and on. My nearest weather station at Tashiro (Gunma pref) has only recorded 0.5mm precipitation so far this August. Normally we would expect double digit rainfall from afternoon thunderstorms on at least a couple of days a week. It's been very hot too - high has hit 30°C twice this summer (today being the second occasion). A massive contrast from July.

It only reached 30°C three times in the 40 years between 1977 (start of operation) and 2017, then 4 times in the big heatwave 2018 and then twice again in 2020... maybe a statistician would argue but it feels like there's been a step change in the local climate.

(I make no apologies for complaining about 30°C whilst everyone else is sweating in the valleys :D )

Looking forward to a change in the weather this weekend.

upload_2020-8-20_17-9-44.png
 
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Sandy

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Looks like Tokyo (and here in Yokohama) will have the hottest average daily maximum temperature on record. I dare say much of Japan will be hitting similar records.
Average daily maximum to 30th August:
Tokyo: 34.2C
Yokohama: 33.7C

Today up to 11am today:
Tokyo: 31.5C
Yokohama: 30.7C

So even if it doesn't rise any more today, the averages for August will be at least:
Tokyo: 34.1C
Yokohama: 33.6C
However, both are likely to hit 33 or 34 degrees today.
 

Ramenman

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Sunshin hours = 150% and Precipitation = less than 20% compared to average August. Many places are like that and it's one of the reasons. Somehow, I didn't feel that hot this summer. Maybe, it's just because I walk less recently. This is precipitation comparison in the past 30 days (compared to average season)
pre30dhi00.png


Sunshine hours
sun30dhi00.png
 

Asama

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Somehow, I didn't feel that hot this summer.
I hear you.
I think one of the reasons is that July was relatively cool, therefore although August has been hot, the summer fatigue hadn't really set in at the beginning of August. I was so glad it wasn't raining, I didn't care that it was hot. It's only been 4 weeks of top level heat so far, when in some years it could be 7 or 8 weeks.
Also the first half of August was very dry, and so less sticky and with cooler evenings and mornings. This made temps more bearable imo.
 
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cold wombat

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Wow, the Darwin climate looks like hell to me!
Either hot and wet... or hot and dry.

Looks like it only rarely drops below 20C?

Darwin weather looks like hell to most of us!

Can anyone say what parts of Japan don't have high humidity in summer?
 

Sandy

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Darwin weather looks like hell to most of us!

Can anyone say what parts of Japan don't have high humidity in summer?
It's the heat and the humidity. Hokkaido is temperate, not tropical/sub-tropical like most of Honshu, Kyushu and Shikoku in summer. So Hokkaido may have humidity, but it's not really hot.
Humidity is low in most places in winter.
 

cold wombat

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It's the heat and the humidity. Hokkaido is temperate, not tropical/sub-tropical like most of Honshu, Kyushu and Shikoku in summer. So Hokkaido may have humidity, but it's not really hot.
Humidity is low in most places in winter.
Humidity does me in unless it's < 20c. I'll take 35 with low humidity over 25 with high humidity every time no matter how much I don't like the heat.
 

Sandy

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It's the heat and the humidity. Hokkaido is temperate, not tropical/sub-tropical like most of Honshu, Kyushu and Shikoku in summer. So Hokkaido may have humidity, but it's not really hot.
Humidity is low in most places in winter.
Humidity does me in unless it's < 20c. I'll take 35 with low humidity over 25 with high humidity every time no matter how much I don't like the heat.
I'd take 40 degrees and 10% humidity, over 32 degrees and 65%+. When I go out each morning for my exercise bike ride(8x 170m uphill), I can feel the humidity between my fingers when I first get out. This morning at 9am it was 29 degrees, 82%.
 

cold wombat

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I'd take 40 degrees and 10% humidity, over 32 degrees and 65%+.
So would I but I'd be desperately looking for a way out of that 40! There is a reason I don't like Perth (apart from the chronic lack of hills).
 

Asama

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Try it here when it's 38 degrees!!!! (there was a 40 a few weeks back!!)
No. Just no. No way.

I only lasted 5 years in Tokyo before heading for the highlands.
That feeling of being permanently damp from June to September... the way my arm makes paper too soggy to write on... having to wear an extra layer just to hide the sweat patches... stripping to underwear the moment I get back into the apartment (I assume everyone in Tokyo does this, but it never gets mentioned???)
Nahhhh.
 

Sandy

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I only lasted 5 years in Tokyo before heading for the highlands.
That feeling of being permanently damp from June to September... the way my arm makes paper too soggy to write on... having to wear an extra layer just to hide the sweat patches... stripping to underwear the moment I get back into the apartment (I assume everyone in Tokyo does this, but it never gets mentioned???)
Nahhhh.
^^ The truth ;)
 

Asama

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Parents in law live in Shinmachi, Gunma. Wife simply will not visit there in Summer.

She grew up there before family moved to Sugita in Kanagawa. She knows that Gunma and Saitama are particularly brutal prefectures.

Proud Gunma resident here!
It's a place of extremes - a cauldron on the plains, paradise (relatively speaking) in the mountains.
 

Asama

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Foehn winds brought some brutal overnight "lows" in Niigata area - Itoigawa and Sanjo stayed above 30C all night (there may be others). Temps still shooting up as typhoon No. 9 passes to the west.
 

Ramenman

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Last month (August) = very long sunshine hours + high temperature + less windy, and the combination made the sea water temperature around Japan record high. Warmer sea water helps stronger typhoons hit Japan, it's what experts have been saying recently.
 

Asama

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Sanjo in Niigata pref hit 40.4C today, a new national record high temperature for September :(

The previous record (set 20 years ago almost to the day) was 39.7C (Saitama), but the previous record for the Hokuriku region was 38.5, so if comparing like-for-like it's a jump of almost 2C.
 
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