Heat wave in Thailand and 4 other countries, 13 to 28 May 2020

Name: Heat wave in Thailand and 4 other countries, 13 to 28 May 2020
Start: 2020-05-13
End: 2020-05-28
Location: Thailand, China, Malaysia, Vietnam, Indonesia

Heat wave in Thailand and 4 other countries, 13 to 28 May 2020: 161 records at 57 stations, peak on 22 May 2020. Closed.

Data as of 2026-10-12. Last revised 12 October 2026 (2026-10-12).

Key Facts

Heat wave in Thailand and 4 other countries, 13 to 28 May 2020 set or tied 161 station records at 57 stations.
It ran from 13 May 2020 to 28 May 2020 (16 days) and its peak day was 22 May 2020.
Status: closed.
Chiang Rai set a daily record high maximum temperature of 39.0 C (102.2 F) on 25 May 2020.
The busiest day was 22 May 2020 with 25 records.
The oldest broken record in the ranked list had stood for 71 years.

Footprint

13 to 28 May 2020

The area covered by Heat wave in Thailand and 4 other countries, 13 to 28 May 2020 is outlined, with 16 of the stations that set records marked, coloured by record type. Made with Natural Earth.

Footprint of Heat wave in Thailand and 4 other countries, 13 to 28 May 2020: stations that set records in the event
Station	Type	Value	Date
Khon Kaen	Record high minimum temperature	28.0 C (82.4 F)	2020-05-21
Roi Et	Record high minimum temperature	29.2 C (84.6 F)	2020-05-21
Chiang Rai	Record high maximum temperature	39.0 C (102.2 F)	2020-05-25
Udon Thani	Record high maximum temperature	40.2 C (104.4 F)	2020-05-14
Sakon Nakhon	Record high minimum temperature	28.5 C (83.3 F)	2020-05-16
Hua Hin	Record high maximum temperature	37.7 C (99.9 F)	2020-05-18
Ko Samui	Record high minimum temperature	29.5 C (85.1 F)	2020-05-19
Nakhon Si Thammarat	Record high minimum temperature	25.7 C (78.3 F)	2020-05-19
Simao	Record high maximum temperature	34.1 C (93.4 F)	2020-05-24
Mae Sot	Record high maximum temperature	39.2 C (102.6 F)	2020-05-24
Lampang	Record high minimum temperature	27.2 C (81.0 F)	2020-05-27
Ubon Ratchathani	Record high minimum temperature	27.5 C (81.5 F)	2020-05-16
Trang	Record high minimum temperature	25.7 C (78.3 F)	2020-05-23
Mae Sariang	Record high minimum temperature	26.5 C (79.7 F)	2020-05-27
Polonia	Record high minimum temperature	25.9 C (78.6 F)	2020-05-21
Phrae	Record high maximum temperature	40.0 C (104.0 F)	2020-05-26

Records per Day

Peak day 25

Records set or tied each day from 13 May 2020 to 28 May 2020. The most in one day was 25 on 22 May 2020.

Records per day during Heat wave in Thailand and 4 other countries, 13 to 28 May 2020
Date	Records
2020-05-13	4
2020-05-14	2
2020-05-15	5
2020-05-16	13
2020-05-17	15
2020-05-18	8
2020-05-19	10
2020-05-20	6
2020-05-21	20
2020-05-22	25
2020-05-23	16
2020-05-24	7
2020-05-25	8
2020-05-26	6
2020-05-27	10
2020-05-28	6

Top Records by Margin

Margin over the record replaced

Top records of Heat wave in Thailand and 4 other countries, 13 to 28 May 2020 ranked by margin
Chiang Rai, 05-25	2.1 C (3.8 F)
Ko Samui, 05-19	1.8 C (3.2 F)
Roi Et, 05-23	1.4 C (2.5 F)
Roi Et, 05-21	1.2 C (2.2 F)
Mae Sot, 05-24	1.2 C (2.2 F)
Khon Kaen, 05-21	1.0 C (1.8 F)
Sakon Nakhon, 05-16	1.0 C (1.8 F)
Roi Et, 05-22	1.0 C (1.8 F)
Polonia, 05-21	0.9 C (1.6 F)
Udon Thani, 05-14	0.8 C (1.4 F)
Lampang, 05-27	0.7 C (1.3 F)
Hua Hin, 05-18	0.7 C (1.3 F)
Simao, 05-24	0.6 C (1.1 F)
Nakhon Si Thammarat, 05-19	0.5 C (0.9 F)
Trang, 05-23	0.5 C (0.9 F)

Margin is how far the new value is beyond the record it replaced. Ties are not shown.

Margin Against Age of the Broken Record

161 records plotted by how far they beat the old record (across) and how many years the old record had stood (up). Long standing records beaten by a wide margin sit in the top right.

Margin against age of the broken record in Heat wave in Thailand and 4 other countries, 13 to 28 May 2020
Margin (C)	Years the old record stood
2.1	63
1.0	62
1.2	62
1.0	63
0.8	71
0.6	68
0.7	57
1.2	63
1.4	62
0.7	63
1.8	33
0.5	59
1.0	62
0.2	68
0.3	62
0.3	62
0.3	63
0.5	51
0.9	39
0.5	65
0.4	63
0.8	57
0.6	57
0.3	63
0.4	63
0.2	63
0.2	62
0.2	57
0.4	54
0.2	62
0.6	45
0.1	61
0.5	51
1.4	22
0.2	57
1.3	33
0.3	56
2.1	33
0.5	40
0.6	37
1.1	37
0.1	51
2.0	13
0.2	48
0.3	48
0.9	22
0.3	41
0.8	37
0.7	33
0.9	37
0.7	37
1.6	4
0.7	37
1.5	10
1.5	28
0.7	37
0.7	37
0.9	33
1.6	28
0.8	33
0.3	40
0.5	33
0.5	33
0.2	37
0.8	19
0.4	37
1.6	10
0.5	22
0.7	37
0.4	33
0.2	33
0.1	37
0.4	28
0.2	45
1.3	22
0.5	32
0.7	10
0.4	21
0.4	22
0.3	26
0.3	25
0.6	28
0.3	33
0.5	28
0.7	25
1.1	17
1.3	6
1.4	7
1.2	7
0.6	24
1.1	5
0.1	28
0.5	10
0.5	10
0.8	25
0.3	33
0.4	1
0.2	23
1.1	6
0.5	22
1.1	3
0.2	22
0.4	25
0.5	8
0.3	33
1.3	13
0.9	10
0.8	7
0.6	5
0.1	33
1.6	1
0.3	17
1.0	6
0.1	17
0.1	17
0.2	10
0.6	10
0.4	10
0.2	10
0.3	10
0.2	10
0.4	8
0.3	4
0.2	17
0.1	13
0.1	9
0.4	4
0.9	5
0.1	15
0.1	10
0.3	6
0.5	6
0.4	6
0.8	1
0.2	7
0.2	7
0.1	10
0.5	7
0.1	8
0.7	3
0.4	4
0.3	4
0.2	6
0.3	5
0.2	5
0.1	10
0.5	3
0.1	7
0.9	6
0.4	6
0.2	3
0.1	6
0.1	5
0.1	6
0.1	7
0.1	4
0.1	4
0.1	6
0.2	1
0.6	5
0.1	3

Compared With Other Events

Station records per event

Station records in Heat wave in Thailand and 4 other countries, 13 to 28 May 2020 compared with similar events
Heat wave in United States and Mexico, 16 January to 14 February 2024	9,869 records
Heat wave in United States, 28 January to 24 February 2026	6,528 records
Heat wave in United States and Mexico, 24 May to 19 June 2020	5,047 records
Heat wave in United States and Mexico, 26 March to 17 April 2021	3,669 records
Heat wave in Germany and 49 other countries, 18 December 2021 to 15 January 2022	3,626 records
Heat wave in Thailand and 4 other countries, 13 to 28 May 2020 (this event)	161 records

Every Record Set

20 of 161

Every record set or tied during Heat wave in Thailand and 4 other countries, 13 to 28 May 2020, in date order
Date	Station	Record	Value	Margin	Years stood	Significance
2020-05-14	Udon Thani	Record high maximum temperature	40.2 C (104.4 F)	0.8 C (1.4 F)	71	30 of 100 (Routine)
2020-05-16	Sakon Nakhon	Record high minimum temperature	28.5 C (83.3 F)	1.0 C (1.8 F)	63	30 of 100 (Routine)
2020-05-16	Ubon Ratchathani	Record high minimum temperature	27.5 C (81.5 F)	0.3 C (0.5 F)	63	27 of 100 (Routine)
2020-05-18	Hua Hin	Record high maximum temperature	37.7 C (99.9 F)	0.7 C (1.3 F)	63	29 of 100 (Routine)
2020-05-19	Ko Samui	Record high minimum temperature	29.5 C (85.1 F)	1.8 C (3.2 F)	33	29 of 100 (Routine)
2020-05-19	Nakhon Si Thammarat	Record high minimum temperature	25.7 C (78.3 F)	0.5 C (0.9 F)	59	29 of 100 (Routine)
2020-05-19	Simao	Record high maximum temperature	33.9 C (93.0 F)	0.2 C (0.4 F)	68	27 of 100 (Routine)
2020-05-21	Khon Kaen	Record high minimum temperature	28.0 C (82.4 F)	1.0 C (1.8 F)	62	32 of 100 (Routine)
2020-05-21	Roi Et	Record high minimum temperature	29.2 C (84.6 F)	1.2 C (2.2 F)	62	32 of 100 (Routine)
2020-05-21	Polonia	Record high minimum temperature	25.9 C (78.6 F)	0.9 C (1.6 F)	39	26 of 100 (Routine)
2020-05-22	Roi Et	Record high maximum temperature	40.0 C (104.0 F)	1.0 C (1.8 F)	62	28 of 100 (Routine)
2020-05-23	Roi Et	Record high maximum temperature	40.3 C (104.5 F)	1.4 C (2.5 F)	62	29 of 100 (Routine)
2020-05-23	Trang	Record high minimum temperature	25.7 C (78.3 F)	0.5 C (0.9 F)	51	27 of 100 (Routine)
2020-05-24	Simao	Record high maximum temperature	34.1 C (93.4 F)	0.6 C (1.1 F)	68	29 of 100 (Routine)
2020-05-24	Mae Sot	Record high maximum temperature	39.2 C (102.6 F)	1.2 C (2.2 F)	63	29 of 100 (Routine)
2020-05-25	Chiang Rai	Record high maximum temperature	39.0 C (102.2 F)	2.1 C (3.8 F)	63	32 of 100 (Routine)
2020-05-25	Mae Sot	Record high minimum temperature	25.8 C (78.4 F)	0.3 C (0.5 F)	62	27 of 100 (Routine)
2020-05-26	Phrae	Record high maximum temperature	40.0 C (104.0 F)	0.5 C (0.9 F)	65	26 of 100 (Routine)
2020-05-27	Lampang	Record high minimum temperature	27.2 C (81.0 F)	0.7 C (1.3 F)	57	29 of 100 (Routine)
2020-05-27	Mae Sariang	Record high minimum temperature	26.5 C (79.7 F)	0.3 C (0.5 F)	62	27 of 100 (Routine)

The daily ledgers keep a limited number of records per day, so this list has 20 of the 161 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 2026-10-12. Events are found by this site from station records and are not official designations. Records are provisional until reprocessed.

Margin (C)	Years the old record stood
2.1	63
1.0	62
1.2	62
1.0	63
0.8	71
0.6	68
0.7	57
1.2	63
1.4	62
0.7	63
1.8	33
0.5	59
1.0	62
0.2	68
0.3	62
0.3	62
0.3	63
0.5	51
0.9	39
0.5	65
0.4	63
0.8	57
0.6	57
0.3	63
0.4	63
0.2	63
0.2	62
0.2	57
0.4	54
0.2	62
0.6	45
0.1	61
0.5	51
1.4	22
0.2	57
1.3	33
0.3	56
2.1	33
0.5	40
0.6	37
1.1	37
0.1	51
2.0	13
0.2	48
0.3	48
0.9	22
0.3	41
0.8	37
0.7	33
0.9	37
0.7	37
1.6	4
0.7	37
1.5	10
1.5	28
0.7	37
0.7	37
0.9	33
1.6	28
0.8	33
0.3	40
0.5	33
0.5	33
0.2	37
0.8	19
0.4	37
1.6	10
0.5	22
0.7	37
0.4	33
0.2	33
0.1	37
0.4	28
0.2	45
1.3	22
0.5	32
0.7	10
0.4	21
0.4	22
0.3	26
0.3	25
0.6	28
0.3	33
0.5	28
0.7	25
1.1	17
1.3	6
1.4	7
1.2	7
0.6	24
1.1	5
0.1	28
0.5	10
0.5	10
0.8	25
0.3	33
0.4	1
0.2	23
1.1	6
0.5	22
1.1	3
0.2	22
0.4	25
0.5	8
0.3	33
1.3	13
0.9	10
0.8	7
0.6	5
0.1	33
1.6	1
0.3	17
1.0	6
0.1	17
0.1	17
0.2	10
0.6	10
0.4	10
0.2	10
0.3	10
0.2	10
0.4	8
0.3	4
0.2	17
0.1	13
0.1	9
0.4	4
0.9	5
0.1	15
0.1	10
0.3	6
0.5	6
0.4	6
0.8	1
0.2	7
0.2	7
0.1	10
0.5	7
0.1	8
0.7	3
0.4	4
0.3	4
0.2	6
0.3	5
0.2	5
0.1	10
0.5	3
0.1	7
0.9	6
0.4	6
0.2	3
0.1	6
0.1	5
0.1	6
0.1	7
0.1	4
0.1	4
0.1	6
0.2	1
0.6	5
0.1	3

Margin (C)	Years the old record stood
2.1	63
1.0	62
1.2	62
1.0	63
0.8	71
0.6	68
0.7	57
1.2	63
1.4	62
0.7	63
1.8	33
0.5	59
1.0	62
0.2	68
0.3	62
0.3	62
0.3	63
0.5	51
0.9	39
0.5	65
0.4	63
0.8	57
0.6	57
0.3	63
0.4	63
0.2	63
0.2	62
0.2	57
0.4	54
0.2	62
0.6	45
0.1	61
0.5	51
1.4	22
0.2	57
1.3	33
0.3	56
2.1	33
0.5	40
0.6	37
1.1	37
0.1	51
2.0	13
0.2	48
0.3	48
0.9	22
0.3	41
0.8	37
0.7	33
0.9	37
0.7	37
1.6	4
0.7	37
1.5	10
1.5	28
0.7	37
0.7	37
0.9	33
1.6	28
0.8	33
0.3	40
0.5	33
0.5	33
0.2	37
0.8	19
0.4	37
1.6	10
0.5	22
0.7	37
0.4	33
0.2	33
0.1	37
0.4	28
0.2	45
1.3	22
0.5	32
0.7	10
0.4	21
0.4	22
0.3	26
0.3	25
0.6	28
0.3	33
0.5	28
0.7	25
1.1	17
1.3	6
1.4	7
1.2	7
0.6	24
1.1	5
0.1	28
0.5	10
0.5	10
0.8	25
0.3	33
0.4	1
0.2	23
1.1	6
0.5	22
1.1	3
0.2	22
0.4	25
0.5	8
0.3	33
1.3	13
0.9	10
0.8	7
0.6	5
0.1	33
1.6	1
0.3	17
1.0	6
0.1	17
0.1	17
0.2	10
0.6	10
0.4	10
0.2	10
0.3	10
0.2	10
0.4	8
0.3	4
0.2	17
0.1	13
0.1	9
0.4	4
0.9	5
0.1	15
0.1	10
0.3	6
0.5	6
0.4	6
0.8	1
0.2	7
0.2	7
0.1	10
0.5	7
0.1	8
0.7	3
0.4	4
0.3	4
0.2	6
0.3	5
0.2	5
0.1	10
0.5	3
0.1	7
0.9	6
0.4	6
0.2	3
0.1	6
0.1	5
0.1	6
0.1	7
0.1	4
0.1	4
0.1	6
0.2	1
0.6	5
0.1	3