Heat wave in United States, 12 March to 1 April 2021

Name: Heat wave in United States, 12 March to 1 April 2021
Start: 2021-03-12
End: 2021-04-01
Location: United States

Heat wave in United States, 12 March to 1 April 2021: 1,030 records at 625 stations, peak on 26 March 2021. Closed.

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

Key Facts

Heat wave in United States, 12 March to 1 April 2021 set or tied 1,030 station records at 625 stations.
It ran from 12 March 2021 to 1 April 2021 (21 days) and its peak day was 26 March 2021.
Status: closed.
Middleboro set a daily record high minimum temperature of 10.6 C (51.1 F) on 26 March 2021.
The busiest day was 26 March 2021 with 346 records.
The oldest broken record in the ranked list had stood for 124 years.

Footprint

12 March to 1 April 2021

The area covered by Heat wave in United States, 12 March to 1 April 2021 is outlined, with 20 of the stations that set records marked, coloured by record type. Made with Natural Earth.

Footprint of Heat wave in United States, 12 March to 1 April 2021: stations that set records in the event
Station	Type	Value	Date
Middleboro	Record high minimum temperature	10.6 C (51.1 F)	2021-03-26
Blue Hill Coop	Record high minimum temperature	10.0 C (50.0 F)	2021-03-26
Atlantic City Marina	Record high maximum temperature	27.2 C (81.0 F)	2021-03-26
Superior	Record high minimum temperature	8.3 C (46.9 F)	2021-03-21
Lowville	Record high minimum temperature	10.0 C (50.0 F)	2021-03-26
Newark Liberty Intl AP	Record high maximum temperature	28.9 C (84.0 F)	2021-03-26
Renovo	Record high minimum temperature	8.3 C (46.9 F)	2021-03-27
Cheboygan	Record high maximum temperature	20.0 C (68.0 F)	2021-03-23
Cornwall	Record high minimum temperature	11.7 C (53.1 F)	2021-03-26
Trinidad	Record high minimum temperature	10.6 C (51.1 F)	2021-03-20
Hemlock	Record high minimum temperature	10.6 C (51.1 F)	2021-03-25
Plant City	Record high maximum temperature	34.4 C (93.9 F)	2021-03-26
Brockton	Record high minimum temperature	12.2 C (54.0 F)	2021-03-26
Ny City Cntrl Park	Record high maximum temperature	27.8 C (82.0 F)	2021-03-26
Libby 32 SSE	Record high maximum temperature	15.6 C (60.1 F)	2021-03-18
Ogdensburg 4 NE	Record high minimum temperature	9.4 C (48.9 F)	2021-03-25
Sussex 1 NW	Record high minimum temperature	9.4 C (48.9 F)	2021-03-26
Mohonk Lake	Record high maximum temperature	23.9 C (75.0 F)	2021-03-26
Talladega	Record high minimum temperature	21.1 C (70.0 F)	2021-03-27
Hightstown 2 W	Record high maximum temperature	27.8 C (82.0 F)	2021-03-27

Records per Day

Peak day 346

Records set or tied each day from 12 March 2021 to 1 April 2021. The most in one day was 346 on 26 March 2021.

Records per day during Heat wave in United States, 12 March to 1 April 2021
Date	Records
2021-03-12	2
2021-03-13	5
2021-03-14	25
2021-03-15	5
2021-03-16	4
2021-03-17	10
2021-03-18	37
2021-03-19	41
2021-03-20	55
2021-03-21	38
2021-03-22	23
2021-03-23	24
2021-03-24	78
2021-03-25	134
2021-03-26	346
2021-03-27	137
2021-03-28	37
2021-03-29	8
2021-03-30	6
2021-03-31	12
2021-04-01	3

Top Records by Margin

Margin over the record replaced

Top records of Heat wave in United States, 12 March to 1 April 2021 ranked by margin
Middleboro, 03-26	6.7 C (12.1 F)
Atlantic City Marina, 03-26	5.0 C (9.0 F)
Lowville, 03-26	4.4 C (7.9 F)
Superior, 03-21	4.4 C (7.9 F)
Blue Hill Coop, 03-26	3.9 C (7.0 F)
Newark Liberty Intl AP, 03-26	3.9 C (7.0 F)
Cornwall, 03-26	3.4 C (6.1 F)
Ny City Cntrl Park, 03-26	3.4 C (6.1 F)
Renovo, 03-27	3.3 C (5.9 F)
Cheboygan, 03-23	3.3 C (5.9 F)
Hemlock, 03-25	2.8 C (5.0 F)
Mohonk Lake, 03-26	2.8 C (5.0 F)
Trinidad, 03-20	2.3 C (4.1 F)
Brockton, 03-26	2.2 C (4.0 F)
Hightstown 2 W, 03-27	2.2 C (4.0 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

500 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, 12 March to 1 April 2021
Margin (C)	Years the old record stood
6.7	116
3.9	100
5.0	92
4.4	100
3.3	122
4.4	111
3.9	111
3.3	100
3.4	100
2.3	114
1.6	104
2.2	116
2.8	100
3.4	99
0.5	79
1.7	110
2.2	112
1.6	116
2.8	99
2.2	111
3.3	92
1.7	100
1.7	100
0.6	124
2.2	92
0.6	72
1.1	100
0.6	110
5.6	82
1.7	103
2.2	99
1.6	100
1.7	108
1.1	108
1.7	100
1.6	111
1.7	123
1.2	120
1.1	108
2.3	99
7.8	67
0.6	76
0.6	114
0.6	121
0.6	104
1.1	120
0.6	116
1.1	116
1.7	99
0.5	100
5.6	78
1.1	110
1.1	96
0.5	108
0.5	66
0.5	114
3.9	84
0.6	100
0.6	111
0.6	100
0.5	111
7.8	58
3.9	82
0.5	100
0.5	120
0.6	111
0.5	114
1.1	92
1.1	92
2.2	92
1.1	92
0.5	99
1.7	92
1.1	66
4.5	76
2.8	82
1.1	87
0.6	92
0.5	95
0.6	92
2.8	83
0.5	73
2.8	84
5.0	72
2.2	82
2.2	82
1.1	87
3.9	72
0.6	92
2.7	82
5.0	67
0.5	86
2.8	76
1.7	80
2.7	75
2.8	76
5.6	68
3.9	68
0.5	92
1.1	83
0.5	83
2.3	75
3.9	75
1.1	82
2.8	82
2.8	82
2.8	72
0.5	82
1.1	84
3.8	75
1.7	76
0.5	84
3.3	72
0.6	83
2.3	72
0.5	87
3.9	72
1.7	76
5.0	58
2.3	72
3.9	72
2.2	75
2.2	75
3.3	72
4.4	58
1.1	72
2.2	72
1.1	74
2.2	72
3.9	58
3.3	68
1.7	68
1.7	72
3.3	62
2.8	72
2.7	72
2.8	67
2.2	75
2.8	72
3.3	58
3.9	58
0.6	72
0.5	75
0.6	76
2.3	76
1.1	72
1.7	67
2.7	68
1.1	54
1.1	72
2.2	72
7.3	44
0.5	76
2.2	75
4.4	58
0.6	82
1.6	72
1.6	75
1.7	75
2.3	71
1.7	71
1.1	75
2.2	72
2.8	68
1.7	72
1.2	74
2.7	68
1.1	74
0.6	76
0.5	72
0.5	72
1.6	71
0.6	68
1.1	68
0.5	68
2.7	68
1.6	72
1.1	76
0.6	72
1.6	76
0.6	75
2.8	67
0.5	72
1.7	43
1.6	72
1.1	72
1.1	72
2.3	72
2.2	68
2.8	58
2.2	68
4.4	64
1.7	72
3.9	56
1.6	67
0.5	68
1.7	68
0.6	68
2.8	60
3.9	58

Compared With Other Events

Station records per event

Station records in Heat wave in United States, 12 March to 1 April 2021 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, 12 March to 1 April 2021 (this event)	1,030 records

Every Record Set

20 of 1,030

Every record set or tied during Heat wave in United States, 12 March to 1 April 2021, in date order
Date	Station	Record	Value	Margin	Years stood	Significance
2021-03-18	Libby 32 SSE	Record high maximum temperature	15.6 C (60.1 F)	1.7 C (3.1 F)	110	43 of 100 (Notable)
2021-03-20	Trinidad	Record high minimum temperature	10.6 C (51.1 F)	2.3 C (4.1 F)	114	44 of 100 (Notable)
2021-03-21	Superior	Record high minimum temperature	8.3 C (46.9 F)	4.4 C (7.9 F)	111	46 of 100 (Notable)
2021-03-23	Cheboygan	Record high maximum temperature	20.0 C (68.0 F)	3.3 C (5.9 F)	100	45 of 100 (Notable)
2021-03-25	Hemlock	Record high minimum temperature	10.6 C (51.1 F)	2.8 C (5.0 F)	100	44 of 100 (Notable)
2021-03-25	Ogdensburg 4 NE	Record high minimum temperature	9.4 C (48.9 F)	2.2 C (4.0 F)	111	43 of 100 (Notable)
2021-03-26	Middleboro	Record high minimum temperature	10.6 C (51.1 F)	6.7 C (12.1 F)	116	53 of 100 (Notable)
2021-03-26	Blue Hill Coop	Record high minimum temperature	10.0 C (50.0 F)	3.9 C (7.0 F)	100	47 of 100 (Notable)
2021-03-26	Atlantic City Marina	Record high maximum temperature	27.2 C (81.0 F)	5.0 C (9.0 F)	92	47 of 100 (Notable)
2021-03-26	Lowville	Record high minimum temperature	10.0 C (50.0 F)	4.4 C (7.9 F)	100	46 of 100 (Notable)
2021-03-26	Newark Liberty Intl AP	Record high maximum temperature	28.9 C (84.0 F)	3.9 C (7.0 F)	111	46 of 100 (Notable)
2021-03-26	Cornwall	Record high minimum temperature	11.7 C (53.1 F)	3.4 C (6.1 F)	100	45 of 100 (Notable)
2021-03-26	Plant City	Record high maximum temperature	34.4 C (93.9 F)	1.6 C (2.9 F)	104	44 of 100 (Notable)
2021-03-26	Brockton	Record high minimum temperature	12.2 C (54.0 F)	2.2 C (4.0 F)	116	44 of 100 (Notable)
2021-03-26	Ny City Cntrl Park	Record high maximum temperature	27.8 C (82.0 F)	3.4 C (6.1 F)	99	44 of 100 (Notable)
2021-03-26	Sussex 1 NW	Record high minimum temperature	9.4 C (48.9 F)	1.6 C (2.9 F)	116	43 of 100 (Notable)
2021-03-26	Mohonk Lake	Record high maximum temperature	23.9 C (75.0 F)	2.8 C (5.0 F)	99	43 of 100 (Notable)
2021-03-27	Renovo	Record high minimum temperature	8.3 C (46.9 F)	3.3 C (5.9 F)	122	46 of 100 (Notable)
2021-03-27	Talladega	Record high minimum temperature	21.1 C (70.0 F)	0.5 C (0.9 F)	79	43 of 100 (Notable)
2021-03-27	Hightstown 2 W	Record high maximum temperature	27.8 C (82.0 F)	2.2 C (4.0 F)	112	43 of 100 (Notable)

The daily ledgers keep a limited number of records per day, so this list has 20 of the 1,030 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
6.7	116
3.9	100
5.0	92
4.4	100
3.3	122
4.4	111
3.9	111
3.3	100
3.4	100
2.3	114
1.6	104
2.2	116
2.8	100
3.4	99
0.5	79
1.7	110
2.2	112
1.6	116
2.8	99
2.2	111
3.3	92
1.7	100
1.7	100
0.6	124
2.2	92
0.6	72
1.1	100
0.6	110
5.6	82
1.7	103
2.2	99
1.6	100
1.7	108
1.1	108
1.7	100
1.6	111
1.7	123
1.2	120
1.1	108
2.3	99
7.8	67
0.6	76
0.6	114
0.6	121
0.6	104
1.1	120
0.6	116
1.1	116
1.7	99
0.5	100
5.6	78
1.1	110
1.1	96
0.5	108
0.5	66
0.5	114
3.9	84
0.6	100
0.6	111
0.6	100
0.5	111
7.8	58
3.9	82
0.5	100
0.5	120
0.6	111
0.5	114
1.1	92
1.1	92
2.2	92
1.1	92
0.5	99
1.7	92
1.1	66
4.5	76
2.8	82
1.1	87
0.6	92
0.5	95
0.6	92
2.8	83
0.5	73
2.8	84
5.0	72
2.2	82
2.2	82
1.1	87
3.9	72
0.6	92
2.7	82
5.0	67
0.5	86
2.8	76
1.7	80
2.7	75
2.8	76
5.6	68
3.9	68
0.5	92
1.1	83
0.5	83
2.3	75
3.9	75
1.1	82
2.8	82
2.8	82
2.8	72
0.5	82
1.1	84
3.8	75
1.7	76
0.5	84
3.3	72
0.6	83
2.3	72
0.5	87
3.9	72
1.7	76
5.0	58
2.3	72
3.9	72
2.2	75
2.2	75
3.3	72
4.4	58
1.1	72
2.2	72
1.1	74
2.2	72
3.9	58
3.3	68
1.7	68
1.7	72
3.3	62
2.8	72
2.7	72
2.8	67
2.2	75
2.8	72
3.3	58
3.9	58
0.6	72
0.5	75
0.6	76
2.3	76
1.1	72
1.7	67
2.7	68
1.1	54
1.1	72
2.2	72
7.3	44
0.5	76
2.2	75
4.4	58
0.6	82
1.6	72
1.6	75
1.7	75
2.3	71
1.7	71
1.1	75
2.2	72
2.8	68
1.7	72
1.2	74
2.7	68
1.1	74
0.6	76
0.5	72
0.5	72
1.6	71
0.6	68
1.1	68
0.5	68
2.7	68
1.6	72
1.1	76
0.6	72
1.6	76
0.6	75
2.8	67
0.5	72
1.7	43
1.6	72
1.1	72
1.1	72
2.3	72
2.2	68
2.8	58
2.2	68
4.4	64
1.7	72
3.9	56
1.6	67
0.5	68
1.7	68
0.6	68
2.8	60
3.9	58

Margin (C)	Years the old record stood
6.7	116
3.9	100
5.0	92
4.4	100
3.3	122
4.4	111
3.9	111
3.3	100
3.4	100
2.3	114
1.6	104
2.2	116
2.8	100
3.4	99
0.5	79
1.7	110
2.2	112
1.6	116
2.8	99
2.2	111
3.3	92
1.7	100
1.7	100
0.6	124
2.2	92
0.6	72
1.1	100
0.6	110
5.6	82
1.7	103
2.2	99
1.6	100
1.7	108
1.1	108
1.7	100
1.6	111
1.7	123
1.2	120
1.1	108
2.3	99
7.8	67
0.6	76
0.6	114
0.6	121
0.6	104
1.1	120
0.6	116
1.1	116
1.7	99
0.5	100
5.6	78
1.1	110
1.1	96
0.5	108
0.5	66
0.5	114
3.9	84
0.6	100
0.6	111
0.6	100
0.5	111
7.8	58
3.9	82
0.5	100
0.5	120
0.6	111
0.5	114
1.1	92
1.1	92
2.2	92
1.1	92
0.5	99
1.7	92
1.1	66
4.5	76
2.8	82
1.1	87
0.6	92
0.5	95
0.6	92
2.8	83
0.5	73
2.8	84
5.0	72
2.2	82
2.2	82
1.1	87
3.9	72
0.6	92
2.7	82
5.0	67
0.5	86
2.8	76
1.7	80
2.7	75
2.8	76
5.6	68
3.9	68
0.5	92
1.1	83
0.5	83
2.3	75
3.9	75
1.1	82
2.8	82
2.8	82
2.8	72
0.5	82
1.1	84
3.8	75
1.7	76
0.5	84
3.3	72
0.6	83
2.3	72
0.5	87
3.9	72
1.7	76
5.0	58
2.3	72
3.9	72
2.2	75
2.2	75
3.3	72
4.4	58
1.1	72
2.2	72
1.1	74
2.2	72
3.9	58
3.3	68
1.7	68
1.7	72
3.3	62
2.8	72
2.7	72
2.8	67
2.2	75
2.8	72
3.3	58
3.9	58
0.6	72
0.5	75
0.6	76
2.3	76
1.1	72
1.7	67
2.7	68
1.1	54
1.1	72
2.2	72
7.3	44
0.5	76
2.2	75
4.4	58
0.6	82
1.6	72
1.6	75
1.7	75
2.3	71
1.7	71
1.1	75
2.2	72
2.8	68
1.7	72
1.2	74
2.7	68
1.1	74
0.6	76
0.5	72
0.5	72
1.6	71
0.6	68
1.1	68
0.5	68
2.7	68
1.6	72
1.1	76
0.6	72
1.6	76
0.6	75
2.8	67
0.5	72
1.7	43
1.6	72
1.1	72
1.1	72
2.3	72
2.2	68
2.8	58
2.2	68
4.4	64
1.7	72
3.9	56
1.6	67
0.5	68
1.7	68
0.6	68
2.8	60
3.9	58