Greybull Threshold Days by Year (USC00484080)

16 fixed thresholds counted per year at Greybull (USC00484080): hot days, frost, tropical nights and heavy rain, with the most days in a year.

Key Facts for Greybull Thresholds

Greybull: days with 10 mm (0.39 in) or more of precipitation in 49 years, most in 1975 with 14.
Greybull: days with 10 cm (3.9 in) or more of snowfall in 32 years, most in 1993 with 11.
Greybull: days with a maximum temperature at or above 30 C (86 F) in 23 years, most in 1988 with 95.
Greybull: days with a maximum temperature at or above 35 C (95 F) in 23 years, most in 2012 with 39.
16 fixed thresholds have at least one qualifying day at Greybull.

Days at or above 30 C (86 F)

23 years with a qualifying day

Days per year at Greybull with a maximum temperature at or above 30 C (86 F), with the decade average as a line. The most was 95 in 1988.

Days at or above 30 C (86 F) per year at Greybull
Year	Days	Decade average
1988	95	88
1989	81	88
1990	85	62.2
1991	74	62.2
1992	48	62.2
1993	29	62.2
1994	69	62.2
1996	71	62.2
1997	56	62.2
1998	68	62.2
1999	60	62.2
2000	76	76.8
2001	88	76.8
2002	66	76.8
2003	77	76.8
2010	61	73.3
2011	73	73.3
2012	87	73.3
2013	87	73.3
2014	55	73.3
2015	70	73.3
2016	76	73.3
2018	77	73.3

For each year, a bar from the first to the last day at Greybull meeting 30 C (86 F).

First to last qualifying date each year at Greybull
Year	First date	Last date
1988	1988-05-13	1988-09-07
1989	1989-04-21	1989-09-30
1990	1990-06-04	1990-09-15
1991	1991-06-11	1991-10-17
1992	1992-05-06	1992-10-03
1993	1993-05-13	1993-09-12
1994	1994-05-27	1994-09-11
1996	1996-06-07	1996-09-13
1997	1997-05-31	1997-09-14
1998	1998-05-26	1998-09-18
1999	1999-05-28	1999-09-17
2000	2000-04-28	2000-09-16
2001	2001-05-12	2001-10-01
2002	2002-05-20	2002-09-16
2003	2003-05-24	2003-10-09
2010	2010-05-28	2010-10-05
2011	2011-06-06	2011-10-02
2012	2012-04-24	2012-09-16
2013	2013-05-13	2013-09-22
2014	2014-05-24	2014-09-27
2015	2015-06-02	2015-10-01
2016	2016-04-23	2016-09-12
2018	2018-04-29	2018-10-03

Every Fixed Threshold

Fixed thresholds at Greybull
Threshold	Years with a qualifying day	Most days in a year	Year	Latest year days
30 C (86 F): Days	23	95	1988	77
35 C (95 F): Days	23	39	2012	27
40 C (104 F): Days	8	4	2002	3
90 F (32.2 C): Days	23	79	1988	59
100 F (37.8 C): Days	18	15	2003	11
0 C (32 F): Ice days (max	23	69	2002	53
0 C (32 F): Frost days (min	23	208	1991	190
-10 C (14 F): Days with min	23	103	1988	100
-20 C (-4 F): Days with min	23	36	1989	23
-30 C (-22 F): Days with min	14	10	1996	3
20 C (68 F): Tropical nights (min	13	3	1988	2
10 mm (0.39 in): Days with 10 mm or more rain	49	14	1975	3
25 mm (0.98 in): Days with 25 mm or more rain	19	4	1975	1
50 mm (1.97 in): Days with 50 mm or more rain	1	1	1988	1
10 cm (3.9 in): Days with 10 cm or more snowfall	32	11	1993	2
25 cm (9.8 in): Days with 25 cm or more snowfall	1	2	1993	2

Years with under 90 percent of days observed are left out of the most days column. Threshold history at this station starts in 1988.

Download the Data

Data for Greybull threshold days by year: CSV or JSON. Field meanings are on the data page.

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 (17 October 2026). Threshold counts are computed by this site.

Data as of 2025-12-31. Last revised 31 December 2025 (2025-12-31).

Greybull Threshold Days by Year (USC00484080)

Key Facts for Greybull Thresholds

Days at or above 30 C (86 F)

Every Fixed Threshold

Download the Data

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