It looks like the winds in Kumamoto will be strongest at about 9 AM tomorrow. The graph shows the probability of winds over 50 knots. According to the page I found at the second address shown below, 50 knots is associated with the following kinds of impacts:
"Whole gale trees uprooted; considerable structural damage occurs"
http://www.jma.go.jp/en/typh/storm-349.html?t=1408
http://www.disastercenter.com/convert.htm

2014-07-09 19:40 JST

I just received an e-mail calling for the evacuation of the Hitoyoshi area. Here's the Google translation of it (which I've tweaked slightly so that it makes more sense):
Hitoyoshi Emergency Response Headquarters
With the approach of typhoon No. 8 large, at 16:00 July 9, 2014, we issued an evacuation advisory to Hitoyoshi throughout.
Please evacuate early.
For information about shelter locations, please visit the home page of Hitoyoshi.
Contact: City Hall Hitoyoshi
人吉市災害対策本部
大型の台風8号の接近にともない、平成26年7月9日16時00分に、人吉市全域に避難勧告を発令しました。
早めの避難をお願いします。
避難場所については、人吉市ホームページをご覧ください。
お問い合わせ先:人吉市役所 
I've been recommending that people not depend on me for evacuation information and sign up to receive evacuation notices directly themselves. For more information, see the following post:
https://www.facebook.com/Kumamotoi/posts/668558819884220

2014-07-09 18:34 JST

This article has some information about school cancelations in Kumamoto for tomorrow the 10th (Thursday):
Kumamoto City: All 8 city-run kindergartens, all 94 elementary schools, all 42 junior high schools. The article doesn't seem to say anything about high schools in Kumamoto City.
Areas in Kumamoto Prefecture outside of Kumamoto City: 145 elementary schools, 59 junior high schools, Kami Amakusa High School, 14 special education schools (for children with special needs).
I think there will be quite a few more cancelations. I can report that my own university, Kumamoto Gakuen University, has canceled all classes for tomorrow. I do not know what decision other universities and high schools in Kumamoto have made or will announce soon.
http://www.yomiuri.co.jp/local/kumamoto/news/20140708-OYTNT50165.html
県教委は8日、熊本市以外の公立の小学校145校と中学校59校、県立上天草高校、県立特別支援学校14校が10日に休校すると発表した。上天草高校と県立特別支援学校2校は9日も休校する。熊本市教委も市立の全幼稚園8園、全小学校94校、全中学校42校を10日は休校とすることを決めた。9日は各園長や学校長の判断で早めの下校といった措置をとる。
台風8号接近 県など最大級の警戒呼び掛け
 大型で非常に強い台風8号の接近を受け、県や熊本地方気象台は8日、県民に対し、早めの自主避難など最大級の警戒を呼び掛けた。県内は9日明け方に強風域、10日未明に暴風域に入るとみられ、同日昼過ぎから夕方にかけて県内に最接近する可能性が高い。7日までの大雨で地盤が緩み、河川が増水しているため、土砂災害や河川の氾濫にも注意を促している。

2014-07-09 18:23 JST

Here's a useful site that was introduced by Karen Laviolette-Nibe in response to another post on this list. Thanks Karen!
http://www.river.go.jp/xbandradar/index.html

2014-07-09 11:23 JST

This web site
http://www.tropicalstormrisk.com
offers an e-mail alert system. Here's the alert I got this morning.

2014-07-09 07:05 JST

From the article:
====START QUOTE=====
Japanese officials are urging people to take the threat posed by Neoguri seriously.
"There are fears about violent winds, high waves and tides and torrential rain that we have never experienced before," Satoshi Ebihara, the Japanese weather agency's chief forecaster, told an evening news conference Monday.
"We are in an abnormal situation where serious danger is imminent," he said.
The World Meteorological Organization said Neoguri was not as powerful as Haiyan, but that "its impact is not to be underestimated".
=====END QUOTE=====
http://news.yahoo.com/japan-highest-typhoon-alert-480-000-urged-shelter-041602217.html
Japan on highest typhoon alert, 480,000 urged to take shelter
Japan braced Tuesday for one of its worst storms in years as typhoon Neoguri barrelled towards the southern Okinawa island chain, with the national weather agency issuing its highest alert and nearly half-a-million people urged to take shelter. The top-level warning means a threat to life, as well a…

2014-07-09 06:27 JST

The probability of getting tropical storm winds (39-73 mph or 63-118 kilometers per hour winds) in the next 36 hours is high:
http://www.tropicalstormrisk.com

2014-07-09 06:17 JST

If you live in an area that is susceptible to flooding or at risk from landslides, the heavy rain etc. that the storm brings may lead to a call to evacuate. I cannot promise to be able to put out such notices for people on Facebook or on the Kumamoto-i mailing list. Accordingly, if you are in a vulnerable area, I strongly recommend that you sign up for the Japanese e-mail warning messages, which you can run through Google translate as soon as you get them. Here's an explanation that I posted earlier about how to do this:
===============
Sign up for the Japanese e-mail warnings at the following address:
http://www.anshin.pref.kumamoto.jp/
If you can't read the Japanese on this page, just send it through Google translate or a similar site:
https://translate.google.com/
Then, when you get a message in Japanese from the prefecture, run it through Google translate.

2014-07-08 21:39 JST

The photo is from 1999 in Shiranui-machi. Homes were flooded when the combination of high tide and the swell from the cyclone caused the levees to be breached. When Typhoon No. 18 arrived that year, it coincided with oshio (大潮), a time in the month when the difference between high tide and low tide is greatest. We will be at the same time of the month when this storm hits us. The winds may not be quite as bad as was first predicted but this storm still could prove to be deadly.
http://cyber.pref.kumamoto.jp/bousai/content/asp/topics/topics_detail.asp?PageID=12&ID=18&pg=1&sort=0&PageType=list
災害記録 / 熊本県防災情報ホームページ
 平成11年9月23日から24日に台風第18号が来襲し、牛深では観測史上最高の最大瞬間風速を記録するなど、暴風が猛威をふるい、さらに、大潮で満潮時刻に近い頃に県南西部に接近したことから、不知火海沿岸を中心に高潮による被害が発生し、特に不知火町では死者12名の大惨事となりました。この台風第18号は、県下各地で死者16名、負傷者315名の人的被害をはじめ、多数の住家に被害を及ぼし、また、農林水産業、土木施設を中心に約1,234億円もの被害を発生させるなど、県内に甚大な被害をもたらしました。

2014-07-08 21:31 JST

The probability of Kumamoto being hit by tropical storm winds in the next 48 hours is, according to this site, fairly high. The probability of having Category 1 or higher winds, however, is fairly low (you can check that out for yourself on the web site):
http://www.tropicalstormrisk.com
Still, a slow-moving storm like this one can dump a lot of water on a place in a relatively short period of time. Even if the winds don't seem too scary, the storm may still be quite dangerous.

2014-07-08 13:48 JST

Good news! According to this, when the typhoon hits Kumamoto, it is now predicted to be a Category 1 tropical storm -- not a Category 4 as was predicted earlier. With winds of 119-153 kilometers per hour (74-95 miles per hour), a Category 1 storm can still cause serious damage but, obviously, it's no where near as dangerous as a Category 4.
http://www.tropicalstormrisk.com

2014-07-08 09:46 JST

Here's the forecast for the next five days. According to this, it looks like we will begin to experience the typhoon tomorrow (Wednesday, July 9th) but that it will be closest to Kumamoto from 3 AM on the 10th (Thursday) to 3 AM on the 11th (Friday).
http://www.jma.go.jp/jp/typh/14085.html
気象庁 | 台風情報

2014-07-08 09:37 JST

"Evacuation of 87,000 people was announced in Kumamoto prefecture in southwestern Japan because of the risk of flooding, said Monday the NHK TV company. The evacuation of the entire population of Amakusa district, which includes the same-name city and its neighboring towns, was announced In Kumamoto Prefecture, according to RIA Novosti reports.
This was caused by the increased risk of flooding due to heavy rains. Only for one hour 70 millimeters of rain fell in the region on Monday morning. In Kumamoto, Kagoshima, Nagasaki prefecture and at Kyushu island 250 millimeters of rain fell yesterday. The Main Japanese Metrological Office warns of increased risks of floods, landslides, mountain avalanches. Kumamoto prefecture reports of landslides in residential areas."
http://voiceofrussia.com/news/2014_07_07/Evacuation-of-87-000-people-due-to-threat-of-flooding-in-Japan-media-7246/
Evacuation of 87,000 people due to threat of flooding in Japan - media
Evacuation of 87,000 people was announced in Kumamoto prefecture in southwestern Japan because of the risk of flooding, said Monday the NHK TV company. The evacuation of the entire population of Amak

2014-07-07 21:23 JST

"In Kyushu, parts of Nagasaki, Kumamoto and Kagoshima prefectures got more than 300 mm of rain from Sunday to Monday, prompting landslide warnings in some areas."
http://www.japantimes.co.jp/news/2014/07/07/national/typhoon-heading-toward-okinawa/
Typhoon heading toward Okinawa | The Japan Times
Typhoon Neoguri was heading northwest toward Okinawa on Monday, bringing the risk of landslides and floods to the remote island chain, the Meteorological A

2014-07-07 21:21 JST

Red alert for Japan’s Kyushu island as landslide loom, evacuation recommended
Japan’s Meteorological Agency has issued a red-level weather alert for the Kagoshima, Kumamoto and Nagasaki prefectures of the island of Kyushu and recommended the evacuation of about 20,000 fr

2014-07-07 21:17 JST

Super-typhoon Neoguri approaches Japan's Okinawa islands
Super-typhoon Neoguri, with gusts of up to 270km per hour, expected to hit southernmost subtropical island chain early Tuesday, possibly reaching mainland Japan by Wednesday

2014-07-07 21:16 JST

This image is from the following site:
http://www.tropicalstormrisk.com

2014-07-07 21:15 JST

This came from the city:
"Tropical Cyclone Information TY 1408 (NEOGURI) is comming close to Kyushu(Kumamoto)
June 11th , 2014
A heavy rain advisory has been issued for the following areas: kumamoto Pref.
Tropical Cyclone Information TY 1408 (NEOGURI) is comming close to Kyushu(Kumamoto).
Please note more Tropical Cyclone information.
Japan Meteorological Agency HP
http://www.jma.go.jp/en/typh/
If you have any concerns, feel free to contact the Kumamoto City International Foundation (Kumamoto City International Center).
(TEL) 096-359-4995 (9a.m.〜8p.m.)"
I appreciate the hard work of the city officials who put this information out in English. I think, though, that we also need an automated system in English (and other languages) that runs in parallel to the Japanese e-mail warning system.
Japan Meteorological Agency | Tropical Cyclone Information

2014-07-07 11:38 JST

This table is the best source I have been able to find so far for information about weather-related warnings. One problem, however, is that it doesn't say anything about the evacuation recommendations for Amakusa. It sure would be nice to have the most important information neatly packaged in one place.
http://www.jma.go.jp/en/warn/349_table.html

2014-07-07 09:20 JST

I won't try to explain what each of the colors and the chicken wire mesh at the top mean in detail because, frankly, the prefecture's explanation doesn't make a lot of sense to me. I can say two things, however. Red is the worst level and it means either that rivers have reached flooding level (or perhaps are already overflowing) or that there's a danger of landslides or both (both are listed as meanings in the key so this too is confusing). Places with chicken-wire mesh over the red have been told to evacuate (though the Japanese explanation does not state this clearly).
A good information science specialist needs to help the prefecture fix their system. The national government's system also has serious problems, such as putting out emergency information in pdf files that must be clicked upon. Still, one positive thing I can say about the prefecture's map is that it does give you a general idea of where the situation is the worse.
http://www.bousai.pref.kumamoto.jp/GmnDsp.exe?M100A0S0N1P0

2014-07-07 08:05 JST