Extreme rain in United States, 26 to 29 August 2018

Name: Extreme rain in United States, 26 to 29 August 2018
Start: 2018-08-26
End: 2018-08-29
Location: United States

Extreme rain in United States, 26 to 29 August 2018: 184 records at 170 stations, peak on 27 August 2018. Closed.

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

Key Facts

Extreme rain in United States, 26 to 29 August 2018 set or tied 184 station records at 170 stations.
It ran from 26 August 2018 to 29 August 2018 (4 days) and its peak day was 27 August 2018.
Status: closed.
Goldbutte 7 N set a daily record precipitation of 38.4 mm (1.5 in) on 28 August 2018.
The busiest day was 27 August 2018 with 124 records.
The oldest broken record in the ranked list had stood for 97 years.

Footprint

26 to 29 August 2018

The area covered by Extreme rain in United States, 26 to 29 August 2018 is outlined, with 20 of the stations that set records marked, coloured by record type. Made with Natural Earth.

Footprint of Extreme rain in United States, 26 to 29 August 2018: stations that set records in the event
Station	Type	Value	Date
Goldbutte 7 N	Record daily precipitation	38.4 mm (1.5 in)	2018-08-28
Sylvan Lake	Record daily precipitation	45.7 mm (1.8 in)	2018-08-27
Flatwillow 4 ENE	Record daily precipitation	27.9 mm (1.1 in)	2018-08-27
Mosby 4 ENE	Record daily precipitation	29.0 mm (1.1 in)	2018-08-27
Grassy Lake	Record daily precipitation	27.9 mm (1.1 in)	2018-08-27
Blackfoot Fire Dept	Record daily precipitation	17.8 mm (0.7 in)	2018-08-27
Bozeman Montana State UNIV	Record daily precipitation	22.9 mm (0.9 in)	2018-08-27
Norris Madison Pwr House	Record daily precipitation	22.4 mm (0.9 in)	2018-08-27
Savage	Record daily precipitation	20.6 mm (0.8 in)	2018-08-27
Asotin 14 SW	Record daily precipitation	21.3 mm (0.8 in)	2018-08-27
Beartooth Lake	Record daily precipitation	15.2 mm (0.6 in)	2018-08-27
Canyon	Record daily precipitation	20.3 mm (0.8 in)	2018-08-27
Sylvan Road	Record daily precipitation	20.3 mm (0.8 in)	2018-08-27
Madison Butte	Record daily precipitation	17.8 mm (0.7 in)	2018-08-27
Ft Benton	Record daily precipitation	13.2 mm (0.5 in)	2018-08-28
Harb	Record daily precipitation	22.9 mm (0.9 in)	2018-08-28
Jackson	Record daily precipitation	12.4 mm (0.5 in)	2018-08-28
Moran 5WNW	Record daily precipitation	23.9 mm (0.9 in)	2018-08-28
Snake Rvr	Record daily precipitation	24.1 mm (0.9 in)	2018-08-28
Bone Springs Div	Record daily precipitation	22.9 mm (0.9 in)	2018-08-29

Records per Day

Peak day 124

Records set or tied each day from 26 August 2018 to 29 August 2018. The most in one day was 124 on 27 August 2018.

Top Records by Margin

Margin over the record replaced

Top records of Extreme rain in United States, 26 to 29 August 2018 ranked by margin
Asotin 14 SW, 08-27	21.3 mm (0.8 in)
Bone Springs Div, 08-29	20.4 mm (0.8 in)
Mosby 4 ENE, 08-27	19.1 mm (0.8 in)
Flatwillow 4 ENE, 08-27	19.0 mm (0.7 in)
Goldbutte 7 N, 08-28	18.6 mm (0.7 in)
Sylvan Road, 08-27	17.8 mm (0.7 in)
Grassy Lake, 08-27	17.7 mm (0.7 in)
Madison Butte, 08-27	15.3 mm (0.6 in)
Canyon, 08-27	15.2 mm (0.6 in)
Harb, 08-28	14.8 mm (0.6 in)
Sylvan Lake, 08-27	12.7 mm (0.5 in)
Moran 5WNW, 08-28	10.7 mm (0.4 in)
Beartooth Lake, 08-27	10.1 mm (0.4 in)
Norris Madison Pwr House, 08-27	7.4 mm (0.29 in)
Jackson, 08-28	5.5 mm (0.22 in)

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

Margin Against Age of the Broken Record

184 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 Extreme rain in United States, 26 to 29 August 2018
Margin (mm)	Years the old record stood
19	53
6	97
7	89
11	48
5	89
13	33
19	40
18	27
15	61
21	41
5	89
20	9
15	27
15	36
5	72
5	80
19	40
4	89
10	31
18	27
16	28
10	61
9	60
5	61
25	21
13	39
16	40
15	12
1	76
5	61
14	40
10	37
7	32
15	8
1	79
9	55
13	28
10	39
8	61
20	13
2	76
13	1
8	27
4	61
9	35
12	9
2	61
13	49
18	27
23	21
11	28
13	40
17	11
4	60
8	33
7	40
13	20
10	39
7	8
25	19
6	48
7	52
6	44
3	33
6	39
6	28
2	47
5	37
8	36
1	61
1	49
10	28
5	23
6	13
4	37
1	61
5	36
13	21
8	28
13	13
2	48
13	28
2	52
7	8
10	16
3	40
2	48
11	28
7	5
9	28
8	27
10	28
15	21
5	13
8	37
3	40
3	14
1	49
4	21
10	28
3	36
3	40
3	28
8	20
5	27
5	39
5	33
1	40
5	36
8	24
3	33
10	17
3	39
1	40
3	36
5	13
6	3
3	37
5	28
3	39
5	23
2	19
5	28
3	28
3	27
8	4
10	9
2	21
0	32
3	16
1	27
5	4
3	27
3	28
3	29
5	9
8	4
5	21
3	36
3	36
1	27
2	28
4	13
1	27
3	28
5	21
8	23
3	32
3	35
3	28
1	13
1	31
2	28
2	21
4	20
2	24
5	8
4	4
1	20
3	16
3	16
8	9
3	28
1	28
3	13
1	28
4	3
3	15
3	21
2	15
3	16
3	16
3	23
3	12
3	4
3	16
1	17
3	8
3	3
3	3
3	16
3	13
3	16
1	4

Compared With Other Events

Station records per event

Station records in Extreme rain in United States, 26 to 29 August 2018 compared with similar events
Extreme rain in United States and Mexico, 23 February to 15 March 2019	2,223 records
Extreme rain in United States, 3 to 19 January 2024	2,133 records
Extreme rain in Australia, 7 to 26 March 2021	2,099 records
Extreme rain in United States and Mexico, 29 September to 19 October 2018	1,970 records
Extreme rain in United States, 19 December 2022 to 13 January 2023	1,941 records
Extreme rain in United States, 26 to 29 August 2018 (this event)	184 records

Every Record Set

20 of 184

Every record set or tied during Extreme rain in United States, 26 to 29 August 2018, in date order
Date	Station	Record	Value	Margin	Years stood	Significance
2018-08-27	Sylvan Lake	Record daily precipitation	45.7 mm (1.8 in)	12.7 mm (0.5 in)	33	47 of 100 (Notable)
2018-08-27	Flatwillow 4 ENE	Record daily precipitation	27.9 mm (1.1 in)	19.0 mm (0.7 in)	40	46 of 100 (Notable)
2018-08-27	Mosby 4 ENE	Record daily precipitation	29.0 mm (1.1 in)	19.1 mm (0.8 in)	40	40 of 100 (Notable)
2018-08-27	Grassy Lake	Record daily precipitation	27.9 mm (1.1 in)	17.7 mm (0.7 in)	27	40 of 100 (Notable)
2018-08-27	Blackfoot Fire Dept	Record daily precipitation	17.8 mm (0.7 in)	5.1 mm (0.20 in)	72	20 of 100 (Routine)
2018-08-27	Bozeman Montana State UNIV	Record daily precipitation	22.9 mm (0.9 in)	5.4 mm (0.21 in)	89	20 of 100 (Routine)
2018-08-27	Norris Madison Pwr House	Record daily precipitation	22.4 mm (0.9 in)	7.4 mm (0.29 in)	89	20 of 100 (Routine)
2018-08-27	Savage	Record daily precipitation	20.6 mm (0.8 in)	4.1 mm (0.16 in)	89	20 of 100 (Routine)
2018-08-27	Asotin 14 SW	Record daily precipitation	21.3 mm (0.8 in)	21.3 mm (0.8 in)	41	20 of 100 (Routine)
2018-08-27	Beartooth Lake	Record daily precipitation	15.2 mm (0.6 in)	10.1 mm (0.4 in)	31	20 of 100 (Routine)
2018-08-27	Canyon	Record daily precipitation	20.3 mm (0.8 in)	15.2 mm (0.6 in)	27	20 of 100 (Routine)
2018-08-27	Sylvan Road	Record daily precipitation	20.3 mm (0.8 in)	17.8 mm (0.7 in)	27	20 of 100 (Routine)
2018-08-27	Madison Butte	Record daily precipitation	17.8 mm (0.7 in)	15.3 mm (0.6 in)	36	20 of 100 (Routine)
2018-08-28	Goldbutte 7 N	Record daily precipitation	38.4 mm (1.5 in)	18.6 mm (0.7 in)	53	51 of 100 (Notable)
2018-08-28	Ft Benton	Record daily precipitation	13.2 mm (0.5 in)	4.6 mm (0.18 in)	80	20 of 100 (Routine)
2018-08-28	Harb	Record daily precipitation	22.9 mm (0.9 in)	14.8 mm (0.6 in)	61	20 of 100 (Routine)
2018-08-28	Jackson	Record daily precipitation	12.4 mm (0.5 in)	5.5 mm (0.22 in)	97	20 of 100 (Routine)
2018-08-28	Moran 5WNW	Record daily precipitation	23.9 mm (0.9 in)	10.7 mm (0.4 in)	48	20 of 100 (Routine)
2018-08-28	Snake Rvr	Record daily precipitation	24.1 mm (0.9 in)	5.0 mm (0.20 in)	89	20 of 100 (Routine)
2018-08-29	Bone Springs Div	Record daily precipitation	22.9 mm (0.9 in)	20.4 mm (0.8 in)	9	20 of 100 (Routine)

The daily ledgers keep a limited number of records per day, so this list has 20 of the 184 records the event counts. The counts above use the full total.

Related Headlines

Third party news, headline and link only

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 (mm)	Years the old record stood
19	53
6	97
7	89
11	48
5	89
13	33
19	40
18	27
15	61
21	41
5	89
20	9
15	27
15	36
5	72
5	80
19	40
4	89
10	31
18	27
16	28
10	61
9	60
5	61
25	21
13	39
16	40
15	12
1	76
5	61
14	40
10	37
7	32
15	8
1	79
9	55
13	28
10	39
8	61
20	13
2	76
13	1
8	27
4	61
9	35
12	9
2	61
13	49
18	27
23	21
11	28
13	40
17	11
4	60
8	33
7	40
13	20
10	39
7	8
25	19
6	48
7	52
6	44
3	33
6	39
6	28
2	47
5	37
8	36
1	61
1	49
10	28
5	23
6	13
4	37
1	61
5	36
13	21
8	28
13	13
2	48
13	28
2	52
7	8
10	16
3	40
2	48
11	28
7	5
9	28
8	27
10	28
15	21
5	13
8	37
3	40
3	14
1	49
4	21
10	28
3	36
3	40
3	28
8	20
5	27
5	39
5	33
1	40
5	36
8	24
3	33
10	17
3	39
1	40
3	36
5	13
6	3
3	37
5	28
3	39
5	23
2	19
5	28
3	28
3	27
8	4
10	9
2	21
0	32
3	16
1	27
5	4
3	27
3	28
3	29
5	9
8	4
5	21
3	36
3	36
1	27
2	28
4	13
1	27
3	28
5	21
8	23
3	32
3	35
3	28
1	13
1	31
2	28
2	21
4	20
2	24
5	8
4	4
1	20
3	16
3	16
8	9
3	28
1	28
3	13
1	28
4	3
3	15
3	21
2	15
3	16
3	16
3	23
3	12
3	4
3	16
1	17
3	8
3	3
3	3
3	16
3	13
3	16
1	4

Margin (mm)	Years the old record stood
19	53
6	97
7	89
11	48
5	89
13	33
19	40
18	27
15	61
21	41
5	89
20	9
15	27
15	36
5	72
5	80
19	40
4	89
10	31
18	27
16	28
10	61
9	60
5	61
25	21
13	39
16	40
15	12
1	76
5	61
14	40
10	37
7	32
15	8
1	79
9	55
13	28
10	39
8	61
20	13
2	76
13	1
8	27
4	61
9	35
12	9
2	61
13	49
18	27
23	21
11	28
13	40
17	11
4	60
8	33
7	40
13	20
10	39
7	8
25	19
6	48
7	52
6	44
3	33
6	39
6	28
2	47
5	37
8	36
1	61
1	49
10	28
5	23
6	13
4	37
1	61
5	36
13	21
8	28
13	13
2	48
13	28
2	52
7	8
10	16
3	40
2	48
11	28
7	5
9	28
8	27
10	28
15	21
5	13
8	37
3	40
3	14
1	49
4	21
10	28
3	36
3	40
3	28
8	20
5	27
5	39
5	33
1	40
5	36
8	24
3	33
10	17
3	39
1	40
3	36
5	13
6	3
3	37
5	28
3	39
5	23
2	19
5	28
3	28
3	27
8	4
10	9
2	21
0	32
3	16
1	27
5	4
3	27
3	28
3	29
5	9
8	4
5	21
3	36
3	36
1	27
2	28
4	13
1	27
3	28
5	21
8	23
3	32
3	35
3	28
1	13
1	31
2	28
2	21
4	20
2	24
5	8
4	4
1	20
3	16
3	16
8	9
3	28
1	28
3	13
1	28
4	3
3	15
3	21
2	15
3	16
3	16
3	23
3	12
3	4
3	16
1	17
3	8
3	3
3	3
3	16
3	13
3	16
1	4

Margin (mm)	Years the old record stood
19	53
6	97
7	89
11	48
5	89
13	33
19	40
18	27
15	61
21	41
5	89
20	9
15	27
15	36
5	72
5	80
19	40
4	89
10	31
18	27
16	28
10	61
9	60
5	61
25	21
13	39
16	40
15	12
1	76
5	61
14	40
10	37
7	32
15	8
1	79
9	55
13	28
10	39
8	61
20	13
2	76
13	1
8	27
4	61
9	35
12	9
2	61
13	49
18	27
23	21
11	28
13	40
17	11
4	60
8	33
7	40
13	20
10	39
7	8
25	19
6	48
7	52
6	44
3	33
6	39
6	28
2	47
5	37
8	36
1	61
1	49
10	28
5	23
6	13
4	37
1	61
5	36
13	21
8	28
13	13
2	48
13	28
2	52
7	8
10	16
3	40
2	48
11	28
7	5
9	28
8	27
10	28
15	21
5	13
8	37
3	40
3	14
1	49
4	21
10	28
3	36
3	40
3	28
8	20
5	27
5	39
5	33
1	40
5	36
8	24
3	33
10	17
3	39
1	40
3	36
5	13
6	3
3	37
5	28
3	39
5	23
2	19
5	28
3	28
3	27
8	4
10	9
2	21
0	32
3	16
1	27
5	4
3	27
3	28
3	29
5	9
8	4
5	21
3	36
3	36
1	27
2	28
4	13
1	27
3	28
5	21
8	23
3	32
3	35
3	28
1	13
1	31
2	28
2	21
4	20
2	24
5	8
4	4
1	20
3	16
3	16
8	9
3	28
1	28
3	13
1	28
4	3
3	15
3	21
2	15
3	16
3	16
3	23
3	12
3	4
3	16
1	17
3	8
3	3
3	3
3	16
3	13
3	16
1	4