Heat wave in United States, 6 to 20 September 2018

Name: Heat wave in United States, 6 to 20 September 2018
Start: 2018-09-06
End: 2018-09-20
Location: United States

Heat wave in United States, 6 to 20 September 2018: 101 records at 36 stations, peak on 11 September 2018. Closed.

Data as of 2026-10-17. Last revised 17 October 2026 (2026-10-17).

Key Facts

Heat wave in United States, 6 to 20 September 2018 set or tied 101 station records at 36 stations.
It ran from 6 September 2018 to 20 September 2018 (15 days) and its peak day was 11 September 2018.
Status: closed.
Cordova AP set a daily record high maximum temperature of 23.9 C (75.0 F) on 13 September 2018.
The busiest day was 11 September 2018 with 18 records.
The oldest broken record in the ranked list had stood for 112 years.

Footprint

6 to 20 September 2018

The area covered by Heat wave in United States, 6 to 20 September 2018 is outlined, with 14 of the stations that set records marked, coloured by record type. Made with Natural Earth.

Footprint of Heat wave in United States, 6 to 20 September 2018: stations that set records in the event
Station	Type	Value	Date
Cordova AP	Record high maximum temperature	23.9 C (75.0 F)	2018-09-13
Yakutat AP	Record high maximum temperature	23.9 C (75.0 F)	2018-09-10
Anchorage Merrill Fld	Record high maximum temperature	20.6 C (69.1 F)	2018-09-14
Kenai AP	Record high maximum temperature	21.1 C (70.0 F)	2018-09-08
Seward AP	Record high maximum temperature	23.9 C (75.0 F)	2018-09-11
Annex Creek	Record high minimum temperature	12.8 C (55.0 F)	2018-09-09
Matanuska Exp Farm	Record high maximum temperature	20.6 C (69.1 F)	2018-09-15
Sitka AP	Record high maximum temperature	21.7 C (71.1 F)	2018-09-10
Juneau AP	Record high maximum temperature	22.2 C (72.0 F)	2018-09-11
Gustavus	Record high maximum temperature	21.7 C (71.1 F)	2018-09-11
King Salmon	Record high maximum temperature	22.2 C (72.0 F)	2018-09-12
Anchorage Ted Stevens Intl AP	Record high maximum temperature	21.1 C (70.0 F)	2018-09-13
Moose Pass 3NW	Record high maximum temperature	18.3 C (64.9 F)	2018-09-08
Cordova N	Record high maximum temperature	18.3 C (64.9 F)	2018-09-14

Records per Day

Peak day 18

Records set or tied each day from 6 September 2018 to 20 September 2018. The most in one day was 18 on 11 September 2018.

Records per day during Heat wave in United States, 6 to 20 September 2018
Date	Records
2018-09-06	4
2018-09-07	3
2018-09-08	6
2018-09-09	7
2018-09-10	6
2018-09-11	18
2018-09-12	13
2018-09-13	13
2018-09-14	14
2018-09-15	8
2018-09-16	2
2018-09-17	1
2018-09-18	2
2018-09-19	1
2018-09-20	3

Top Records by Margin

Margin over the record replaced

Top records of Heat wave in United States, 6 to 20 September 2018 ranked by margin
Cordova AP, 09-13	3.9 C (7.0 F)
Yakutat AP, 09-10	3.3 C (5.9 F)
Yakutat AP, 09-11	3.3 C (5.9 F)
Seward AP, 09-11	2.8 C (5.0 F)
Sitka AP, 09-10	2.8 C (5.0 F)
King Salmon, 09-12	2.8 C (5.0 F)
Anchorage Ted Stevens Intl AP, 09-13	2.8 C (5.0 F)
Anchorage Merrill Fld, 09-14	2.3 C (4.1 F)
Yakutat AP, 09-07	2.2 C (4.0 F)
Kenai AP, 09-08	1.7 C (3.1 F)
Kenai AP, 09-14	1.7 C (3.1 F)
Annex Creek, 09-09	1.7 C (3.1 F)
Juneau AP, 09-11	1.6 C (2.9 F)
Cordova N, 09-14	1.6 C (2.9 F)
Anchorage Merrill Fld, 09-11	1.2 C (2.2 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

101 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 United States, 6 to 20 September 2018
Margin (C)	Years the old record stood
3.9	92
3.3	88
2.3	99
1.7	111
1.7	112
1.2	96
2.8	76
1.7	83
0.6	95
2.8	68
1.2	80
0.6	88
1.6	76
1.1	76
2.8	61
2.8	61
3.3	32
0.5	76
2.2	44
1.6	63
0.5	76
2.2	52
0.5	41
3.3	52
2.3	55
0.6	67
0.6	39
0.5	32
3.3	20
3.4	28
0.5	60
1.1	39
0.5	60
3.3	32
2.3	40
1.7	2
2.2	32
1.7	44
2.8	32
0.6	48
1.7	39
1.1	28
1.1	37
2.2	32
1.1	0
1.1	40
1.7	20
1.6	32
3.9	4
2.2	8
2.2	8
1.1	39
1.1	37
1.6	20
0.6	33
1.6	20
0.6	32
0.5	2
1.1	32
1.1	33
0.6	28
1.7	7
1.6	8
1.1	28
0.5	36
0.6	33
0.5	32
1.1	20
1.1	20
2.8	8
2.8	8
1.1	23
0.6	32
1.7	11
1.1	32
0.6	15
1.7	4
1.7	4
1.1	20
1.1	16
0.6	20
0.5	28
1.1	20
0.5	32
0.5	28
1.7	8
1.1	23
1.1	20
2.2	0
0.2	32
0.2	32
1.1	8
1.1	12
0.5	12
0.5	8
1.0	12
0.9	12
0.6	1
0.5	8
0.9	1
0.2	8

Compared With Other Events

Station records per event

Station records in Heat wave in United States, 6 to 20 September 2018 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 United States, 6 to 20 September 2018 (this event)	101 records

Every Record Set

20 of 101

Every record set or tied during Heat wave in United States, 6 to 20 September 2018, in date order
Date	Station	Record	Value	Margin	Years stood	Significance
2018-09-07	Yakutat AP	Record high maximum temperature	22.2 C (72.0 F)	2.2 C (4.0 F)	44	31 of 100 (Routine)
2018-09-08	Kenai AP	Record high maximum temperature	21.1 C (70.0 F)	1.7 C (3.1 F)	112	45 of 100 (Notable)
2018-09-08	Moose Pass 3NW	Record high maximum temperature	18.3 C (64.9 F)	0.5 C (0.9 F)	76	31 of 100 (Routine)
2018-09-09	Annex Creek	Record high minimum temperature	12.8 C (55.0 F)	1.7 C (3.1 F)	83	41 of 100 (Notable)
2018-09-10	Yakutat AP	Record high maximum temperature	23.9 C (75.0 F)	3.3 C (5.9 F)	88	49 of 100 (Notable)
2018-09-10	Sitka AP	Record high maximum temperature	21.7 C (71.1 F)	2.8 C (5.0 F)	68	38 of 100 (Notable)
2018-09-11	Anchorage Merrill Fld	Record high maximum temperature	20.6 C (69.1 F)	1.2 C (2.2 F)	96	42 of 100 (Notable)
2018-09-11	Seward AP	Record high maximum temperature	23.9 C (75.0 F)	2.8 C (5.0 F)	76	42 of 100 (Notable)
2018-09-11	Juneau AP	Record high maximum temperature	22.2 C (72.0 F)	1.6 C (2.9 F)	76	36 of 100 (Notable)
2018-09-11	Gustavus	Record high maximum temperature	21.7 C (71.1 F)	1.1 C (2.0 F)	76	36 of 100 (Notable)
2018-09-11	Yakutat AP	Record high maximum temperature	23.3 C (73.9 F)	3.3 C (5.9 F)	32	32 of 100 (Routine)
2018-09-12	King Salmon	Record high maximum temperature	22.2 C (72.0 F)	2.8 C (5.0 F)	61	34 of 100 (Routine)
2018-09-13	Cordova AP	Record high maximum temperature	23.9 C (75.0 F)	3.9 C (7.0 F)	92	50 of 100 (Notable)
2018-09-13	Anchorage Ted Stevens Intl AP	Record high maximum temperature	21.1 C (70.0 F)	2.8 C (5.0 F)	61	33 of 100 (Routine)
2018-09-14	Anchorage Merrill Fld	Record high maximum temperature	20.6 C (69.1 F)	2.3 C (4.1 F)	99	46 of 100 (Notable)
2018-09-14	Kenai AP	Record high maximum temperature	20.6 C (69.1 F)	1.7 C (3.1 F)	111	45 of 100 (Notable)
2018-09-14	Matanuska Exp Farm	Record high maximum temperature	20.6 C (69.1 F)	1.2 C (2.2 F)	80	37 of 100 (Notable)
2018-09-14	Cordova N	Record high maximum temperature	18.3 C (64.9 F)	1.6 C (2.9 F)	63	30 of 100 (Routine)
2018-09-15	Matanuska Exp Farm	Record high maximum temperature	20.6 C (69.1 F)	0.6 C (1.1 F)	95	39 of 100 (Notable)
2018-09-16	Anchorage Merrill Fld	Record high minimum temperature	10.6 C (51.1 F)	0.6 C (1.1 F)	88	37 of 100 (Notable)

The daily ledgers keep a limited number of records per day, so this list has 20 of the 101 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.

Margin (C)	Years the old record stood
3.9	92
3.3	88
2.3	99
1.7	111
1.7	112
1.2	96
2.8	76
1.7	83
0.6	95
2.8	68
1.2	80
0.6	88
1.6	76
1.1	76
2.8	61
2.8	61
3.3	32
0.5	76
2.2	44
1.6	63
0.5	76
2.2	52
0.5	41
3.3	52
2.3	55
0.6	67
0.6	39
0.5	32
3.3	20
3.4	28
0.5	60
1.1	39
0.5	60
3.3	32
2.3	40
1.7	2
2.2	32
1.7	44
2.8	32
0.6	48
1.7	39
1.1	28
1.1	37
2.2	32
1.1	0
1.1	40
1.7	20
1.6	32
3.9	4
2.2	8
2.2	8
1.1	39
1.1	37
1.6	20
0.6	33
1.6	20
0.6	32
0.5	2
1.1	32
1.1	33
0.6	28
1.7	7
1.6	8
1.1	28
0.5	36
0.6	33
0.5	32
1.1	20
1.1	20
2.8	8
2.8	8
1.1	23
0.6	32
1.7	11
1.1	32
0.6	15
1.7	4
1.7	4
1.1	20
1.1	16
0.6	20
0.5	28
1.1	20
0.5	32
0.5	28
1.7	8
1.1	23
1.1	20
2.2	0
0.2	32
0.2	32
1.1	8
1.1	12
0.5	12
0.5	8
1.0	12
0.9	12
0.6	1
0.5	8
0.9	1
0.2	8

Margin (C)	Years the old record stood
3.9	92
3.3	88
2.3	99
1.7	111
1.7	112
1.2	96
2.8	76
1.7	83
0.6	95
2.8	68
1.2	80
0.6	88
1.6	76
1.1	76
2.8	61
2.8	61
3.3	32
0.5	76
2.2	44
1.6	63
0.5	76
2.2	52
0.5	41
3.3	52
2.3	55
0.6	67
0.6	39
0.5	32
3.3	20
3.4	28
0.5	60
1.1	39
0.5	60
3.3	32
2.3	40
1.7	2
2.2	32
1.7	44
2.8	32
0.6	48
1.7	39
1.1	28
1.1	37
2.2	32
1.1	0
1.1	40
1.7	20
1.6	32
3.9	4
2.2	8
2.2	8
1.1	39
1.1	37
1.6	20
0.6	33
1.6	20
0.6	32
0.5	2
1.1	32
1.1	33
0.6	28
1.7	7
1.6	8
1.1	28
0.5	36
0.6	33
0.5	32
1.1	20
1.1	20
2.8	8
2.8	8
1.1	23
0.6	32
1.7	11
1.1	32
0.6	15
1.7	4
1.7	4
1.1	20
1.1	16
0.6	20
0.5	28
1.1	20
0.5	32
0.5	28
1.7	8
1.1	23
1.1	20
2.2	0
0.2	32
0.2	32
1.1	8
1.1	12
0.5	12
0.5	8
1.0	12
0.9	12
0.6	1
0.5	8
0.9	1
0.2	8