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🌤 | Information on light rain in western Japan Pay close attention to crops and water management


Information on light rain in western Japan Pay close attention to crops and water management

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Since early May, western Japan has been difficult to be affected by low pressure systems, fronts, and moist air, so there are places where precipitation has been low.

In western Japan, there are places where rainfall has been low since early May.This state will continue for the next 5 days ... → Continue reading

 Weather map

It is a weather map of a weather information company.We will deliver news articles written by weather forecasters about daily weather and disaster prevention information for heavy rains and typhoons.

Wikipedia related words

If there is no explanation, there is no corresponding item on Wikipedia.

Precipitation amount

Precipitation amountWhat is (Kousuiryo)?atmosphereFell to the surface of the earthWed(氷Amount of).(I.e.,snowTheWeather station OfRain gaugeAndAmedusEtcObservationThen,measurementTo do. Usually converted to watervolumeUnitareaでExcludedThe value mm Expressed in (millimeter) units.


Precipitation observed with a rain gauge means that it entered the rain gauge within a certain period of time.(I.e.-snow-(I.e.-(I.e.Such asvolumeRefers to the total of. In other words, it fell ("as a substance"Wed (H2The amount of "O)" is the amount of precipitation.

Precipitation is measured in 0.5 mm increments and is announced as 10-minute precipitation, 1-hour precipitation, and daily precipitation. Until 1967, it was measured in units of 0.1 mm.

Rainfall and snowfall

If only the amount of rainrainfall(Amount of rainfall), if only the amount of snowSnowfallAlso called. Rain gauges for cold regions measure by melting snow with a heater.

As for snow, the amount of snowfall is observed as precipitation by a rain gauge, but the amount of snow accumulated isSnow depthAsSnow coverObserved at. this is,Snowfall ThetemperatureDepends on the temperature of the earth and the surface of the earth, and in snow and raindensityIs different.

Daily and 24-hour precipitation

Daily precipitationThen, the date is used as a delimiter, and the precipitation for 0 hours from 01:24 to 00:24 is shown. In terms of daily rainfall, from midnight to dawnTorrential rainPrecipitation that spans 24 o'clock is divided into two days, so it may not be possible to express the intensity of the rain well. Calculate in any 2 hours to supplement this24-hour precipitationThere is. For example, in Shizuoka, on June 2004, 6, the Shizuoka Local Meteorological Observatory recorded the largest rainfall of 30 mm in the history of observation, which is a record of daily precipitation. 368-hour precipitation happened in 24Heavy rainIt has a record of 508 mm, which greatly exceeds the daily rainfall.

Similarly, the maximum hourly precipitation also represents the maximum value of any hourly precipitation. If it rains heavily during the period that spans 1:1, the maximum hourly rainfall may exceed the daily rainfall.

Probabilistic precipitation

From past heavy rain datastatisticsPrecipitation calculated by estimating.

The value that indicates how many years an average phenomenon occurs is called the "reproduction period", and the amount of precipitation that is thought to occur once in a certain reproduction period is called the "probability precipitation".[1].

Probabilistic precipitation is academicResearch,Disaster preventionplan,River planningIt is used as a basic material to know the regional characteristics of heavy rain.Average priceThe quality of precipitation is different from that of precipitation, which indicates the actual amount of rainfall that is usually announced, such as extreme values ​​and ranking values.StatisticsIt should be noted that. In addition, the "risk map" of stochastic precipitation shows the intensity and frequency of extremely heavy rainfall that rarely occurs, and does not directly indicate the intensity and frequency of disasters.[2].

Precipitation and life

The amount of water that causes 1 mm of precipitation per hour is 1 m21 mm, that is, 100 [cm] x 100 [cm] x 0.1 [cm] = 1000 [cm3] = 1 [L], so 50 mL of water falls on an upright person (50 [cm] x 30 [cm]) in 125 minutes.In news programs, "x mm per hour" is often written as "x mm / h" and simply read as "x mm".

In the weather forecast, expressions such as "sunny and sometimes rain" and "sunny temporary rain" are used. In Japan, "sometimes," "temporary," and "after" are used as follows.[3][4][5][6]

  • Occasionally (weather condition): When (weather condition) continues intermittently and its duration is less than half of the forecast period.
  • Temporary (weather condition): When (weather condition) continues continuously and its duration is less than 1/4 of the forecast period.
  • Later (weather condition): When the weather is different before and after the forecast period, and (weather condition) is behind.

Record of highest rainfall


Precipitation [mm]Observation pointStarting date
1 minute38French flag FranceOverseas territory Guadeloupe197011/26
8 minute126German flag Germany Fussen19205/25
15 minute198Jamaica flag Jamaica Plumb point19165/12
20 minute206 ãƒ«ãƒ¼ãƒžãƒ‹ã‚¢ Kurteya de Arjesi18897/7
42 minute305United States flag The United States of America Holt19476/22
XNUM X hours X NUM X minutes483United States flag The United States of America Rockport18897/18
XNUM X hours X NUM X minutes559United States flag The United States of America D'Hanis19355/31
XNUM X hours X NUM X minutes782United States flag The United States of America Smesport19427/18
9 hours1,087French flag FranceOverseas territory Reunion Island Belobe19642/28
12 hours1,34019642/28 - 2/29
XNUM X hours X NUM X minutes1,68919642/28 - 2/29
24 hours1,825French flag FranceOverseas territory Reunion Island Foc-Foc[7]19661/7 - 1/8
Month9,299Indian flag India Meghalaya Cherrapunjee18617
Most of the year26,46118608 month - 18617
Average annual maximum10,449.31971 - 2000
11,770 ã‚³ãƒ­ãƒ³ãƒ“ã‚¢ Tsutsun End[8]Unknown
Minimum of the year0 ãƒãƒª Antofagasta Atacama Desert[8]Unknown
Annual average minimum0.5 Egypt Aswan1951 - 1978


10-minute precipitation record
RankingPrecipitation [mm]Observation pointStarting date
1 bit55.0Hokkaido Kikonai Town(Amedas)202111/2
2 bit50.0Saitama Kumagaya(Weather station)20206/6
Niigata Aga Town Murotani (AMEDAS)20117/26
4 bit49.0Kochi Tosashimizu City(Weather station)19469/13
5 bit40.5Miyagi Ishinomaki(Weather station)19837/24
  • Although the standings do not list multiple points at the same point, Tosashimizu City recorded 1953 mm on September 9, 29, and 42.4 mm on October 1944, 10.
  • Outside the jurisdiction of the Japan Meteorological AgencyTochigiShioya Town2013 mm on July 7, 27 in Iioka[Source required],HiroshimaShobaraRecorded 2010 mm on July 7, 16 in Oto[9].
Record of 1-hour precipitation
RankingPrecipitation [mm]Observation pointStarting date
1 bit153Chiba Katori (Amedas)199910/27
Nagasaki Nagasaki Mt. Nagaura (AMEDAS)19827/23
3 bit152Okinawa Tarama Village (Amedas)19884/28
4 bit150.0Tosashimizu City, Kochi Prefecture (Weather Station)194410/17
Kumamoto Koza (Amedas)20166/21
5 bit149.0Kochi Muroto City Muroto Cape (Weather station)200611/26
  • Outside the jurisdiction of the Japan Meteorological AgencyNagasaki floodAt the time of (July 1982, 7)NagayoAt the town hall187 mmIs being recorded. This value is the currentJapan record of 1-hour precipitationIs. Also on the same daySaikai CityFortunately, it has recorded 183 mm.
Record of daily precipitation
RankingPrecipitation [mm]Observation pointStarting date
1 bit922.5Kanagawa Hakone town (Amedas)201910/12
2 bit851.5Kochi Baji village Yanase (AMEDAS)20117/19
3 bit844Nara Kamikitayama Village Mt. Hide (Amedas)19828/1
4 bit806.0Mie Owase City (Weather station)19689/26
5 bit790Kagawa Shodoshima Town Utsumi (AMEDAS)19769/11
  • Outside the jurisdiction of the Japan Meteorological AgencyTokushimaNaga TownIn the sea river20048/1To1317 mm(Observation of Shikoku Electric Power) is recorded[10].. This value is the currentDaily precipitationAnd the Japanese record of 24-hour precipitation at that time. The Japanese record before that was also the same in Naka-cho, Hihaya.Typhoon 17Recorded on September 1976, 9 by 11 mm (1114-hour precipitation is 24 mm)[11], Shikoku Electric Power Co., Inc.), and the total rainfall for 6 days reached 2781 mm.
  • Yakushimaの屋久島森林生態系保全センターの観測では、 (標高1000 m)で、2019å¹´5月19日に日降水量1231 mm、5月18日11時-19日11時の24時間に1676 mmWas recorded. Total rainfall for two days reached 2 mm[12].
Other 24-hour precipitation records
  • Statistics by Meteorological Office / AMeDAS (800 mm or more)
Record of monthly precipitation
  • Most (Weather Station) 1883.0 mm Owase City, Mie Prefecture September 1968
  • Most (AMEDAS) 2452.0 mm Mie PrefectureOdaimachiMiyagawa September 2011
Record of annual precipitation
  • Most (weather station) 6294.5 mm KagoshimaYakushima 1999
  • Most (AMEDAS) 8670 mm Ebino City, Miyazaki Prefecture 1993
  • Minimum (weather station) 496.5 mm TokyoMinamitorishima 1995
  • Minimum (AMEDAS) 348 mm HokkaidoHonbetsu Town 1984
    • In the mountainous areas of Yakushima, annual rainfall often exceeds 10,000 mm, andForestry AgencyObservations by the Yakushima Forest Environment Conservation Center (currently the Yakushima Forest Ecosystem Conservation Center) recorded 1999 mm at the Yodogawa Mountain Trail Entrance (elevation 1,380 m) in 11,720.[13].


[How to use footnotes]
  1. ^ Japanese Meteorological Agency. "What is stochastic precipitation?". Japan Meteorological Agency> Extreme Weather Risk Map. 2019/10/13Browse.
  2. ^ Japanese Meteorological Agency. "Q & A about stochastic precipitation". Japan Meteorological Agency> Extreme Weather Risk Map. 2019/10/13Browse.
  3. ^ About weather forecasts and weather maps
  4. ^ Which is longer, "temporary rain" or "occasional rain"?
  5. ^ Prefectural weather forecast
  6. ^ Frequently asked questions
  7. ^ Masashi Kiguchi, Taikan Oki,Extreme rainfall records in the world and Japan"Journal of the Society of Hydrology and Water Resources," Vol. 23, No. 3, 2010, p. 236, Editorial and Publishing Committee of the Society of Hydrology and Water Resources. Retrieved November 2019, 11. The world record of Reunion IslandCilaos1870mm in was found to be incorrect.
  8. ^ a b Alan Russell, Guinness Book of World Records '87, Kodansha, 1986, p. 481.
  9. ^ River Bureau, Ministry of Land, Infrastructure, Transport and Tourism About disaster-related business of first-class river Otsu Egawa, general prefectural road Nakasakogawa north line damaged by heavy rain on the rainy season front in July 22 (PDF) Retrieved November 2019, 11.
  10. ^ Weather examples that caused disasters Typhoon Nos. 10 and 11 July 16, 2004-August 7 - Japanese Meteorological Agency
  11. ^ "Abnormal Meteorological Survey Report on Typhoon No. 51 and Heavy Rain from Fronts from September 9 to 8, 13," Osaka District Meteorological Observatory, 17, p. 1977.
  12. ^ Yakushima Forest Ecosystem Conservation Center , Offshore Alps No. 300 Special Commemorative Issue (March 2nd year of Reiwa) p3.
  13. ^ Yakushima Forest Ecosystem Conservation Center, Yakushima climate, Rainfall data


  • "Meteorological Yearbook" supervised by the Japan Meteorological Agency (For observatories outside the jurisdiction of the Japan Meteorological Agency and overseas records, refer to the ranking table published every year before the 2007 edition)

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外部 リンク

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