Heat wave in United States, 23 to 31 July 2018

Name: Heat wave in United States, 23 to 31 July 2018
Start: 2018-07-23
End: 2018-07-31
Location: United States

Heat wave in United States, 23 to 31 July 2018: 136 records at 85 stations, peak on 25 July 2018. Closed.

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

Key Facts

Heat wave in United States, 23 to 31 July 2018 set or tied 136 station records at 85 stations.
It ran from 23 July 2018 to 31 July 2018 (9 days) and its peak day was 25 July 2018.
Status: closed.
Middleboro set a daily record high minimum temperature of 21.7 C (71.1 F) on 28 July 2018.
The busiest day was 25 July 2018 with 46 records.
The oldest broken record in the ranked list had stood for 123 years.

Footprint

23 to 31 July 2018

The area covered by Heat wave in United States, 23 to 31 July 2018 is outlined, with 15 of the stations that set records marked, coloured by record type. Made with Natural Earth.

Footprint of Heat wave in United States, 23 to 31 July 2018: stations that set records in the event
Station	Type	Value	Date
Woodstock	Record high minimum temperature	20.6 C (69.1 F)	2018-07-26
Middleboro	Record high minimum temperature	21.7 C (71.1 F)	2018-07-28
Lowell	Record high minimum temperature	23.3 C (73.9 F)	2018-07-24
Pittsfield Muni AP	Record high minimum temperature	21.7 C (71.1 F)	2018-07-23
First Connecticut Lake	Record high minimum temperature	18.9 C (66.0 F)	2018-07-24
Cornwall	Record high minimum temperature	22.2 C (72.0 F)	2018-07-25
Madison	Record high minimum temperature	21.1 C (70.0 F)	2018-07-26
Boonton 1 SE	Record high minimum temperature	21.7 C (71.1 F)	2018-07-26
Brockton	Record high minimum temperature	23.9 C (75.0 F)	2018-07-24
Greenville Muni AP	Record high minimum temperature	20.0 C (68.0 F)	2018-07-25
Presque Isle	Record high minimum temperature	21.7 C (71.1 F)	2018-07-25
Newport	Record high minimum temperature	21.7 C (71.1 F)	2018-07-25
Farmington	Record high minimum temperature	21.7 C (71.1 F)	2018-07-25
Barre Falls Dam	Record high minimum temperature	22.8 C (73.0 F)	2018-07-24
Berlin	Record high minimum temperature	20.0 C (68.0 F)	2018-07-26

Records per Day

Peak day 46

Records set or tied each day from 23 July 2018 to 31 July 2018. The most in one day was 46 on 25 July 2018.

Top Records by Margin

Margin over the record replaced

Top records of Heat wave in United States, 23 to 31 July 2018 ranked by margin
Pittsfield Muni AP, 07-23	2.3 C (4.1 F)
Newport, 07-25	2.3 C (4.1 F)
Middleboro, 07-28	1.7 C (3.1 F)
Woodstock, 07-26	1.7 C (3.1 F)
Brockton, 07-24	1.7 C (3.1 F)
Greenville Muni AP, 07-25	1.7 C (3.1 F)
Presque Isle, 07-25	1.7 C (3.1 F)
Lowell, 07-24	1.1 C (2.0 F)
Farmington, 07-25	1.1 C (2.0 F)
First Connecticut Lake, 07-26	1.1 C (2.0 F)
Woodstock, 07-24	1.1 C (2.0 F)
Berlin, 07-26	1.1 C (2.0 F)
Middleboro, 07-26	0.6 C (1.1 F)
First Connecticut Lake, 07-24	0.6 C (1.1 F)
Boonton 1 SE, 07-26	0.6 C (1.1 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

136 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, 23 to 31 July 2018
Margin (C)	Years the old record stood
1.7	123
1.7	119
1.1	117
2.3	92
0.5	101
0.6	117
0.6	100
0.6	123
0.5	101
1.7	83
1.7	80
1.7	76
2.3	77
1.1	80
1.1	80
1.1	83
0.5	83
0.6	29
1.1	77
0.6	80
2.8	56
2.2	68
0.6	83
2.8	64
0.5	69
1.2	56
1.1	68
2.3	56
1.7	56
1.6	56
0.5	56
3.3	51
0.5	56
1.6	56
0.6	65
1.6	56
1.1	59
1.1	56
1.1	59
1.1	56
0.6	56
1.2	55
1.7	55
1.1	56
0.5	55
0.5	59
0.5	59
0.5	59
1.1	55
1.1	51
0.6	45
1.1	48
0.6	56
1.1	48
2.3	39
3.3	24
1.7	32
3.3	27
3.4	19
1.7	39
1.1	31
1.1	31
2.2	31
1.7	39
1.1	40
1.1	39
0.6	32
2.8	32
2.2	19
2.3	31
1.7	32
1.1	24
1.1	23
1.2	31
1.6	31
0.6	31
2.2	28
1.1	31
0.6	24
1.1	33
0.6	40
0.6	32
1.1	16
2.2	24
0.5	31
1.1	33
1.6	31
0.6	32
0.6	27
1.7	16
0.5	39
0.5	39
0.6	16
0.5	33
0.5	39
1.1	31
1.7	7
1.7	31
0.5	24
0.6	24
0.5	24
0.5	23
1.1	8
0.5	28
0.6	23
0.5	23
1.1	1
1.1	1
0.5	7
2.2	8
0.6	16
0.6	23
0.6	24
1.1	16
0.6	7
0.6	23
0.5	5
0.6	15
0.5	1
0.5	7
0.5	16
0.6	23
0.6	7
0.6	8
0.6	23
0.5	16
0.5	7
0.6	7
0.5	12
0.5	16
1.7	7
1.7	8
0.5	7
0.6	8
0.5	8
0.5	8

Compared With Other Events

Station records per event

Station records in Heat wave in United States, 23 to 31 July 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, 23 to 31 July 2018 (this event)	136 records

Every Record Set

20 of 136

Every record set or tied during Heat wave in United States, 23 to 31 July 2018, in date order
Date	Station	Record	Value	Margin	Years stood	Significance
2018-07-23	Pittsfield Muni AP	Record high minimum temperature	21.7 C (71.1 F)	2.3 C (4.1 F)	92	42 of 100 (Notable)
2018-07-23	Greenville Muni AP	Record high minimum temperature	18.9 C (66.0 F)	0.6 C (1.1 F)	80	34 of 100 (Routine)
2018-07-24	Lowell	Record high minimum temperature	23.3 C (73.9 F)	1.1 C (2.0 F)	117	43 of 100 (Notable)
2018-07-24	First Connecticut Lake	Record high minimum temperature	18.9 C (66.0 F)	0.6 C (1.1 F)	100	41 of 100 (Notable)
2018-07-24	Brockton	Record high minimum temperature	23.9 C (75.0 F)	1.7 C (3.1 F)	83	39 of 100 (Notable)
2018-07-24	Woodstock	Record high minimum temperature	21.7 C (71.1 F)	1.1 C (2.0 F)	83	36 of 100 (Notable)
2018-07-24	Farmington	Record high minimum temperature	21.1 C (70.0 F)	0.5 C (0.9 F)	83	35 of 100 (Notable)
2018-07-24	Barre Falls Dam	Record high minimum temperature	22.8 C (73.0 F)	0.6 C (1.1 F)	29	35 of 100 (Notable)
2018-07-25	Cornwall	Record high minimum temperature	22.2 C (72.0 F)	0.5 C (0.9 F)	101	41 of 100 (Notable)
2018-07-25	Greenville Muni AP	Record high minimum temperature	20.0 C (68.0 F)	1.7 C (3.1 F)	80	37 of 100 (Notable)
2018-07-25	Presque Isle	Record high minimum temperature	21.7 C (71.1 F)	1.7 C (3.1 F)	76	37 of 100 (Notable)
2018-07-25	Newport	Record high minimum temperature	21.7 C (71.1 F)	2.3 C (4.1 F)	77	37 of 100 (Notable)
2018-07-25	Farmington	Record high minimum temperature	21.7 C (71.1 F)	1.1 C (2.0 F)	80	36 of 100 (Notable)
2018-07-26	Woodstock	Record high minimum temperature	20.6 C (69.1 F)	1.7 C (3.1 F)	119	44 of 100 (Notable)
2018-07-26	Madison	Record high minimum temperature	21.1 C (70.0 F)	0.5 C (0.9 F)	101	41 of 100 (Notable)
2018-07-26	Middleboro	Record high minimum temperature	21.7 C (71.1 F)	0.6 C (1.1 F)	117	41 of 100 (Notable)
2018-07-26	Boonton 1 SE	Record high minimum temperature	21.7 C (71.1 F)	0.6 C (1.1 F)	123	41 of 100 (Notable)
2018-07-26	First Connecticut Lake	Record high minimum temperature	19.4 C (66.9 F)	1.1 C (2.0 F)	80	36 of 100 (Notable)
2018-07-26	Berlin	Record high minimum temperature	20.0 C (68.0 F)	1.1 C (2.0 F)	77	35 of 100 (Notable)
2018-07-28	Middleboro	Record high minimum temperature	21.7 C (71.1 F)	1.7 C (3.1 F)	123	44 of 100 (Notable)

The daily ledgers keep a limited number of records per day, so this list has 20 of the 136 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
1.7	123
1.7	119
1.1	117
2.3	92
0.5	101
0.6	117
0.6	100
0.6	123
0.5	101
1.7	83
1.7	80
1.7	76
2.3	77
1.1	80
1.1	80
1.1	83
0.5	83
0.6	29
1.1	77
0.6	80
2.8	56
2.2	68
0.6	83
2.8	64
0.5	69
1.2	56
1.1	68
2.3	56
1.7	56
1.6	56
0.5	56
3.3	51
0.5	56
1.6	56
0.6	65
1.6	56
1.1	59
1.1	56
1.1	59
1.1	56
0.6	56
1.2	55
1.7	55
1.1	56
0.5	55
0.5	59
0.5	59
0.5	59
1.1	55
1.1	51
0.6	45
1.1	48
0.6	56
1.1	48
2.3	39
3.3	24
1.7	32
3.3	27
3.4	19
1.7	39
1.1	31
1.1	31
2.2	31
1.7	39
1.1	40
1.1	39
0.6	32
2.8	32
2.2	19
2.3	31
1.7	32
1.1	24
1.1	23
1.2	31
1.6	31
0.6	31
2.2	28
1.1	31
0.6	24
1.1	33
0.6	40
0.6	32
1.1	16
2.2	24
0.5	31
1.1	33
1.6	31
0.6	32
0.6	27
1.7	16
0.5	39
0.5	39
0.6	16
0.5	33
0.5	39
1.1	31
1.7	7
1.7	31
0.5	24
0.6	24
0.5	24
0.5	23
1.1	8
0.5	28
0.6	23
0.5	23
1.1	1
1.1	1
0.5	7
2.2	8
0.6	16
0.6	23
0.6	24
1.1	16
0.6	7
0.6	23
0.5	5
0.6	15
0.5	1
0.5	7
0.5	16
0.6	23
0.6	7
0.6	8
0.6	23
0.5	16
0.5	7
0.6	7
0.5	12
0.5	16
1.7	7
1.7	8
0.5	7
0.6	8
0.5	8
0.5	8

Margin (C)	Years the old record stood
1.7	123
1.7	119
1.1	117
2.3	92
0.5	101
0.6	117
0.6	100
0.6	123
0.5	101
1.7	83
1.7	80
1.7	76
2.3	77
1.1	80
1.1	80
1.1	83
0.5	83
0.6	29
1.1	77
0.6	80
2.8	56
2.2	68
0.6	83
2.8	64
0.5	69
1.2	56
1.1	68
2.3	56
1.7	56
1.6	56
0.5	56
3.3	51
0.5	56
1.6	56
0.6	65
1.6	56
1.1	59
1.1	56
1.1	59
1.1	56
0.6	56
1.2	55
1.7	55
1.1	56
0.5	55
0.5	59
0.5	59
0.5	59
1.1	55
1.1	51
0.6	45
1.1	48
0.6	56
1.1	48
2.3	39
3.3	24
1.7	32
3.3	27
3.4	19
1.7	39
1.1	31
1.1	31
2.2	31
1.7	39
1.1	40
1.1	39
0.6	32
2.8	32
2.2	19
2.3	31
1.7	32
1.1	24
1.1	23
1.2	31
1.6	31
0.6	31
2.2	28
1.1	31
0.6	24
1.1	33
0.6	40
0.6	32
1.1	16
2.2	24
0.5	31
1.1	33
1.6	31
0.6	32
0.6	27
1.7	16
0.5	39
0.5	39
0.6	16
0.5	33
0.5	39
1.1	31
1.7	7
1.7	31
0.5	24
0.6	24
0.5	24
0.5	23
1.1	8
0.5	28
0.6	23
0.5	23
1.1	1
1.1	1
0.5	7
2.2	8
0.6	16
0.6	23
0.6	24
1.1	16
0.6	7
0.6	23
0.5	5
0.6	15
0.5	1
0.5	7
0.5	16
0.6	23
0.6	7
0.6	8
0.6	23
0.5	16
0.5	7
0.6	7
0.5	12
0.5	16
1.7	7
1.7	8
0.5	7
0.6	8
0.5	8
0.5	8