Heat wave in Japan and Korea, South, 21 to 31 August 2018
Heat wave in Japan and Korea, South, 21 to 31 August 2018: 211 records at 88 stations, peak on 26 August 2018. Closed.
Data as of . Last revised (2026-10-17).
Key Facts
- Heat wave in Japan and Korea, South, 21 to 31 August 2018 set or tied 211 station records at 88 stations.
- It ran from 21 August 2018 to 31 August 2018 (11 days) and its peak day was 26 August 2018.
- Status: closed.
- Fukuyama set an all-time record high minimum temperature of 27.6 C (81.7 F) on 22 August 2018.
- The busiest day was 22 August 2018 with 34 records.
- The oldest broken record in the ranked list had stood for 71 years.
Footprint
21 to 31 August 2018| Station | Type | Value | Date |
|---|---|---|---|
| Fukuyama | Record high minimum temperature | 27.6 C (81.7 F) | 2018-08-22 |
| Niigata | Record high maximum temperature | 39.9 C (103.8 F) | 2018-08-23 |
| Mito | Record high minimum temperature | 27.0 C (80.6 F) | 2018-08-24 |
| Sakai | Record high maximum temperature | 38.5 C (101.3 F) | 2018-08-22 |
| Wakamatsu | Record high maximum temperature | 38.5 C (101.3 F) | 2018-08-23 |
| Yamagata | Record high maximum temperature | 39.0 C (102.2 F) | 2018-08-23 |
| Akita | Record high maximum temperature | 37.6 C (99.7 F) | 2018-08-23 |
| Matsuyama | Record high maximum temperature | 36.9 C (98.4 F) | 2018-08-25 |
| Choshi | Record high maximum temperature | 33.1 C (91.6 F) | 2018-08-26 |
| Hamada | Record high maximum temperature | 37.4 C (99.3 F) | 2018-08-22 |
| Mokpo | Record high minimum temperature | 26.2 C (79.2 F) | 2018-08-30 |
| Irozaki | Record high minimum temperature | 26.7 C (80.1 F) | 2018-08-25 |
| Tsu | Record high maximum temperature | 36.7 C (98.1 F) | 2018-08-26 |
| Omaezaki | Record high minimum temperature | 26.3 C (79.3 F) | 2018-08-29 |
| Kanazawa | Record high maximum temperature | 36.6 C (97.9 F) | 2018-08-24 |
| Nikko | Record high minimum temperature | 19.4 C (66.9 F) | 2018-08-24 |
| Karuizawa | Record high minimum temperature | 20.6 C (69.1 F) | 2018-08-25 |
| Hamamatsu | Record high maximum temperature | 35.8 C (96.4 F) | 2018-08-26 |
| Irako | Record high maximum temperature | 35.3 C (95.5 F) | 2018-08-27 |
| Aikawa | Record high maximum temperature | 37.8 C (100.0 F) | 2018-08-23 |
Records per Day
Peak day 34| Date | Records |
|---|---|
| 2018-08-21 | 18 |
| 2018-08-22 | 34 |
| 2018-08-23 | 27 |
| 2018-08-24 | 25 |
| 2018-08-25 | 28 |
| 2018-08-26 | 34 |
| 2018-08-27 | 14 |
| 2018-08-28 | 8 |
| 2018-08-29 | 7 |
| 2018-08-30 | 7 |
| 2018-08-31 | 9 |
Top Records by Margin
Margin over the record replaced| Akita, 08-23 | |
|---|---|
| Hamada, 08-22 | |
| Matsuyama, 08-25 | |
| Karuizawa, 08-25 | |
| Nikko, 08-24 | |
| Niigata, 08-23 | |
| Tsu, 08-26 | |
| Omaezaki, 08-29 | |
| Mokpo, 08-30 | |
| Irako, 08-27 | |
| Hamamatsu, 08-26 | |
| Choshi, 08-26 | |
| Kanazawa, 08-24 | |
| Irozaki, 08-25 | |
| Fukuyama, 08-22 |
Margin is how far the new value is beyond the record it replaced. Ties are not shown.
Margin Against Age of the Broken Record
| Margin (C) | Years the old record stood |
|---|---|
| 0.4 | 61 |
| 1.4 | 40 |
| 0.3 | 40 |
| 0.4 | 24 |
| 0.4 | 24 |
| 0.1 | 24 |
| 3.5 | 48 |
| 0.6 | 71 |
| 2.2 | 51 |
| 2.6 | 48 |
| 0.8 | 59 |
| 1.2 | 65 |
| 0.9 | 56 |
| 0.5 | 67 |
| 0.6 | 67 |
| 1.7 | 52 |
| 0.8 | 65 |
| 0.7 | 65 |
| 1.6 | 51 |
| 0.4 | 0 |
| 0.7 | 56 |
| 0.3 | 0 |
| 0.5 | 64 |
| 0.6 | 65 |
| 0.3 | 65 |
| 0.4 | 65 |
| 0.5 | 63 |
| 0.8 | 53 |
| 1.0 | 52 |
| 0.3 | 60 |
| 0.4 | 60 |
| 2.3 | 43 |
| 0.7 | 57 |
| 0.3 | 56 |
| 0.5 | 60 |
| 0.6 | 56 |
| 0.7 | 53 |
| 0.3 | 60 |
| 2.8 | 32 |
| 0.4 | 24 |
| 0.4 | 53 |
| 0.2 | 56 |
| 0.2 | 57 |
| 0.4 | 53 |
| 0.2 | 53 |
| 1.1 | 36 |
| 0.6 | 47 |
| 0.1 | 53 |
| 1.1 | 39 |
| 1.1 | 44 |
| 0.7 | 45 |
| 0.1 | 51 |
| 1.2 | 32 |
| 1.2 | 36 |
| 0.6 | 39 |
| 2.2 | 23 |
| 1.0 | 35 |
| 1.3 | 24 |
| 0.8 | 32 |
| 3.2 | 11 |
| 0.6 | 39 |
| 1.0 | 32 |
| 1.1 | 31 |
| 1.5 | 28 |
| 1.2 | 29 |
| 0.2 | 44 |
| 2.3 | 23 |
| 0.2 | 40 |
| 1.0 | 27 |
| 1.9 | 23 |
| 1.2 | 28 |
| 0.1 | 40 |
| 0.8 | 29 |
| 1.2 | 28 |
| 0.6 | 29 |
| 0.3 | 33 |
| 0.5 | 29 |
| 0.2 | 41 |
| 2.2 | 13 |
| 1.4 | 23 |
| 0.4 | 39 |
| 1.8 | 23 |
| 0.1 | 33 |
| 0.9 | 23 |
| 0.6 | 28 |
| 0.5 | 29 |
| 1.3 | 23 |
| 1.7 | 23 |
| 1.1 | 20 |
| 0.2 | 32 |
| 0.3 | 31 |
| 2.7 | 5 |
| 1.3 | 23 |
| 1.0 | 23 |
| 0.2 | 29 |
| 0.9 | 23 |
| 1.1 | 11 |
| 1.0 | 12 |
| 0.2 | 32 |
| 2.0 | 0 |
| 0.3 | 27 |
| 0.9 | 23 |
| 0.5 | 23 |
| 1.3 | 5 |
| 0.7 | 23 |
| 0.7 | 23 |
| 0.4 | 24 |
| 0.6 | 24 |
| 0.7 | 23 |
| 0.2 | 24 |
| 0.8 | 24 |
| 0.6 | 23 |
| 0.4 | 23 |
| 0.6 | 23 |
| 0.5 | 23 |
| 1.7 | 5 |
| 0.5 | 23 |
| 0.9 | 16 |
| 0.5 | 23 |
| 0.3 | 23 |
| 2.0 | 5 |
| 1.3 | 11 |
| 0.4 | 23 |
| 0.3 | 23 |
| 1.0 | 8 |
| 0.5 | 23 |
| 0.1 | 23 |
| 0.2 | 23 |
| 0.1 | 23 |
| 0.3 | 17 |
| 1.4 | 8 |
| 1.5 | 1 |
| 0.8 | 11 |
| 1.0 | 8 |
| 0.1 | 23 |
| 0.1 | 23 |
| 0.4 | 17 |
| 0.3 | 25 |
| 0.1 | 17 |
| 1.2 | 8 |
| 0.6 | 15 |
| 0.1 | 17 |
| 0.6 | 4 |
| 1.3 | 5 |
| 0.3 | 17 |
| 0.2 | 17 |
| 1.5 | 5 |
| 0.5 | 8 |
| 0.2 | 19 |
| 0.8 | 8 |
| 0.8 | 8 |
| 1.3 | 5 |
| 0.8 | 8 |
| 1.2 | 5 |
| 0.4 | 8 |
| 1.0 | 5 |
| 0.8 | 1 |
| 1.1 | 0 |
| 0.5 | 8 |
| 0.6 | 8 |
| 1.0 | 5 |
| 1.0 | 5 |
| 0.6 | 4 |
| 1.0 | 5 |
| 0.3 | 11 |
| 0.3 | 8 |
| 0.3 | 8 |
| 0.5 | 5 |
| 0.7 | 0 |
| 0.2 | 11 |
| 0.5 | 8 |
| 0.3 | 8 |
| 0.1 | 11 |
| 0.3 | 8 |
| 0.3 | 8 |
| 0.3 | 8 |
| 0.5 | 8 |
| 1.0 | 0 |
| 0.9 | 1 |
| 0.4 | 8 |
| 0.2 | 8 |
| 0.5 | 4 |
| 1.2 | 1 |
| 0.2 | 16 |
| 0.2 | 17 |
| 0.3 | 8 |
| 0.1 | 8 |
| 0.4 | 4 |
| 0.5 | 4 |
| 0.1 | 8 |
| 0.4 | 0 |
| 0.7 | 0 |
| 0.8 | 0 |
| 0.3 | 8 |
| 0.5 | 4 |
| 0.1 | 8 |
| 0.1 | 8 |
| 0.1 | 8 |
| 0.4 | 1 |
| 0.7 | 0 |
Compared With Other Events
Station records per event| Heat wave in United States and Mexico, 16 January to 14 February 2024 | |
|---|---|
| Heat wave in United States, 28 January to 24 February 2026 | |
| Heat wave in United States and Mexico, 24 May to 19 June 2020 | |
| Heat wave in United States and Mexico, 26 March to 17 April 2021 | |
| Heat wave in Germany and 49 other countries, 18 December 2021 to 15 January 2022 | |
| Heat wave in Japan and Korea, South, 21 to 31 August 2018 (this event) |
Every Record Set
20 of 211| Date | Station | Record | Value | Margin | Years stood | Significance |
|---|---|---|---|---|---|---|
| 2018-08-22 | Fukuyama | Record high minimum temperature | 27.6 C (81.7 F) | 0.4 C (0.7 F) | 61 | 46 of 100 (Notable) |
| 2018-08-22 | Sakai | Record high maximum temperature | 38.5 C (101.3 F) | 0.4 C (0.7 F) | 24 | 34 of 100 (Routine) |
| 2018-08-22 | Hamada | Record high maximum temperature | 37.4 C (99.3 F) | 2.6 C (4.7 F) | 48 | 30 of 100 (Routine) |
| 2018-08-23 | Niigata | Record high maximum temperature | 39.9 C (103.8 F) | 1.4 C (2.5 F) | 40 | 42 of 100 (Notable) |
| 2018-08-23 | Wakamatsu | Record high maximum temperature | 38.5 C (101.3 F) | 0.4 C (0.7 F) | 24 | 34 of 100 (Routine) |
| 2018-08-23 | Yamagata | Record high maximum temperature | 39.0 C (102.2 F) | 0.1 C (0.2 F) | 24 | 33 of 100 (Routine) |
| 2018-08-23 | Akita | Record high maximum temperature | 37.6 C (99.7 F) | 3.5 C (6.3 F) | 48 | 31 of 100 (Routine) |
| 2018-08-23 | Aikawa | Record high maximum temperature | 37.8 C (100.0 F) | 0.4 C (0.7 F) | 0 | 27 of 100 (Routine) |
| 2018-08-24 | Mito | Record high minimum temperature | 27.0 C (80.6 F) | 0.3 C (0.5 F) | 40 | 39 of 100 (Notable) |
| 2018-08-24 | Kanazawa | Record high maximum temperature | 36.6 C (97.9 F) | 0.6 C (1.1 F) | 67 | 28 of 100 (Routine) |
| 2018-08-24 | Nikko | Record high minimum temperature | 19.4 C (66.9 F) | 1.6 C (2.9 F) | 51 | 28 of 100 (Routine) |
| 2018-08-25 | Matsuyama | Record high maximum temperature | 36.9 C (98.4 F) | 2.2 C (4.0 F) | 51 | 31 of 100 (Routine) |
| 2018-08-25 | Irozaki | Record high minimum temperature | 26.7 C (80.1 F) | 0.5 C (0.9 F) | 67 | 29 of 100 (Routine) |
| 2018-08-25 | Karuizawa | Record high minimum temperature | 20.6 C (69.1 F) | 1.7 C (3.1 F) | 52 | 28 of 100 (Routine) |
| 2018-08-26 | Choshi | Record high maximum temperature | 33.1 C (91.6 F) | 0.6 C (1.1 F) | 71 | 31 of 100 (Routine) |
| 2018-08-26 | Tsu | Record high maximum temperature | 36.7 C (98.1 F) | 1.2 C (2.2 F) | 65 | 29 of 100 (Routine) |
| 2018-08-26 | Hamamatsu | Record high maximum temperature | 35.8 C (96.4 F) | 0.7 C (1.3 F) | 65 | 28 of 100 (Routine) |
| 2018-08-27 | Irako | Record high maximum temperature | 35.3 C (95.5 F) | 0.8 C (1.4 F) | 65 | 28 of 100 (Routine) |
| 2018-08-29 | Omaezaki | Record high minimum temperature | 26.3 C (79.3 F) | 0.9 C (1.6 F) | 56 | 29 of 100 (Routine) |
| 2018-08-30 | Mokpo | Record high minimum temperature | 26.2 C (79.2 F) | 0.8 C (1.4 F) | 59 | 30 of 100 (Routine) |
The daily ledgers keep a limited number of records per day, so this list has 20 of the 211 records the event counts. The counts above use the full total.
Download the Data
Source: NOAA National Centers for Environmental Information, Global Historical Climatology Network Daily (GHCN-Daily). Records are computed by World Extreme Weather Monitor and are not official NOAA products. (US Government open data (NOAA NCEI)) Data as of 2026-10-17. Events are found by this site from station records and are not official designations. Records are provisional until reprocessed.