What is the hottest month at Yellowstone?

July, with an average high of 81°F and an average low of 48°F at Mammoth Hot Springs (NOAA 1991–2020 normals). The station averages 6 days a year at or above 90°F.

How cold does Yellowstone get in winter?

January is the coldest month, averaging a low of 12°F and a high of 31°F at Mammoth Hot Springs. About 202 nights a year drop to freezing or below.

Does it snow at Yellowstone?

Yes. Mammoth Hot Springs averages 71.5 inches of snow a year, mostly in January, February, March, April, May, October, November and December. Higher ground in the park gets more.

When is the rainy season at Yellowstone?

June is the wettest month on average (1.9 inches of precipitation at Mammoth Hot Springs); the station's annual total is 14.8 inches.

How many hours of daylight does Yellowstone get?

About 15h 32m on June 15 and 8h 50m on December 15 (sunrise 5:36 AM, sunset 9:09 PM in June; 7:52 AM to 4:42 PM in December, America/Denver time).

What is the best month to visit Yellowstone for weather?

By NOAA's normals, average highs sit between 55°F and 85°F in May, June, July, August and September. Of those, May is also well below the park's peak crowds. Weather in the park varies with elevation; this is the Mammoth Hot Springs station.

Weather by month

Yellowstone weather, month by month

Last verified October 6, 2026NOAA 1991–2020 normalsAmerica/Denver time

Average highs, lows, rain, snow and daylight for every month. Measured at the Mammoth Hot Springs (6,195 ft, 0.2 mi from Albright Visitor Center) — with Old Faithful and Lake Yellowstone below, because the park's weather changes with elevation.

The sun sets behind the sharp point of a snow-covered mountain; pink clouds are reflected in a pond — Photo: NPS / Jacob W. Frank

Jul high: 81°F; hottest month
Jan low: 12°F; coldest month
Rain + snowmelt: 14.8in / yr; wettest: Jun
Snowfall: 71.5in / yr; Oct–May
Days ≥ 90°F: 6/ yr
Nights ≤ 32°F: 202/ yr

Mammoth Hot Springs

Month by month

Normals are 30-year averages (1991–2020). Crowds = each month’s share of the park’s busiest month, from NPS visitor counts. Sunrise and sunset are for the 15th of each month in 2027.

Average high and low, every monthbars run from the low to the high · tan strip = precipitation

Month	High	Low	Rain	Snow	Wet days	Sunrise	Sunset	Daylight	Crowds
Jan	31°	12°	0.9″	11.5″	11	7:56 AM	5:07 PM	9h 12m	5
Feb	34°	12°	0.8″	11.5″	11	7:23 AM	5:50 PM	10h 27m	5
Mar	42°	19°	1.1″	10.9″	11	7:35 AM	7:27 PM	11h 53m	4
Apr	50°	26°	1.4″	7.8″	11	6:38 AM	8:06 PM	13h 28m	8
May	60°	35°	1.8″	1.7″	13	5:54 AM	8:43 PM	14h 48m	55
Jun	70°	42°	1.9″	0.3″	13	5:36 AM	9:09 PM	15h 32m	90
Jul	81°	48°	1.3″	—	9	5:51 AM	9:05 PM	15h 14m	100
Aug	80°	47°	1.1″	—	9	6:25 AM	8:29 PM	14h 04m	89
Sep	69°	39°	1.2″	0.6″	9	7:01 AM	7:34 PM	12h 33m	86
Oct	54°	29°	1.3″	4.7″	10	7:37 AM	6:39 PM	11h 01m	33
Nov	39°	19°	1.1″	9.9″	10	7:19 AM	4:55 PM	9h 36m	3
Dec	30°	12°	0.9″	12.6″	12	7:52 AM	4:42 PM	8h 50m	4

Sweet spot: May combines average highs between 55°F and 85°F with crowds under 60% of the peak month. Check what is open in those months — quiet can also mean closed roads.

Also measured at

Old Faithful

The geyser basins, 1,100 ft higher. 7,351 ft, 0.2 mi from Old Faithful Visitor Education Center.

Month	High	Low	Rain	Snow	Wet days
Jan	28°	1°	2.1″	35.6″	14
Feb	31°	2°	2.1″	29.9″	13
Mar	39°	10°	2.2″	27.1″	12
Apr	46°	19°	2.4″	17.1″	12
May	55°	29°	2.7″	5.4″	13
Jun	65°	35°	2.4″	0.6″	13
Jul	76°	39°	1.3″	—	9
Aug	75°	37°	1.4″	—	9
Sep	65°	30°	1.7″	0.9″	10
Oct	50°	22°	2.3″	9.0″	10
Nov	35°	10°	2.2″	26.4″	12
Dec	27°	1°	2.8″	45.0″	15

Also measured at

Lake Yellowstone

The lake and Canyon area. 7,892 ft, 1 mi from Fishing Bridge Visitor Center and Trailside Museum.

Month	High	Low	Rain	Snow	Wet days
Jan	23°	3°	2.0″	35.8″	17
Feb	27°	4°	1.8″	30.9″	15
Mar	35°	11°	2.0″	25.1″	14
Apr	42°	19°	2.1″	22.9″	12
May	50°	29°	2.4″	6.9″	11
Jun	61°	36°	2.5″	1.0″	13
Jul	71°	43°	1.3″	—	10
Aug	71°	42°	1.5″	—	10
Sep	61°	34°	1.6″	1.4″	10
Oct	46°	25°	1.6″	10.2″	9
Nov	33°	15°	1.8″	29.8″	12
Dec	24°	7°	2.0″	35.4″	17

How to read this

These are NOAA’s official 1991–2020 climate normals for one weather station, not a model of the whole park. The station is the one with complete temperature and precipitation normals nearest to a visitor center (we chose Mammoth Hot Springs because it is park headquarters). Highs and lows are daily averages for the month; “wet days” are days with at least 0.01 inch of precipitation. Mountain parks can be 10–20 °F cooler at their high points than at the station, and the NPS weather page for Yellowstone is the place for current conditions and seasonal closures.

Sunrise and sunset are computed with the NOAA solar equations for the park’s coordinates and shown in America/Denver time for the 15th of each month of 2027; they are accurate to about a minute.

Sources · 3

1.U.S. Climate Normals 1991–2020 — monthly normals station inventory · National Centers for Environmental Information (NOAA)
2.Yellowstone National Park — Weather (nps.gov) · National Park Service
3.Yellowstone National Park — Visitor Use Statistics · National Park Service (IRMA)

FAQ

Yellowstone weather questions

What is the hottest month at Yellowstone?: July, with an average high of 81°F and an average low of 48°F at Mammoth Hot Springs (NOAA 1991–2020 normals). The station averages 6 days a year at or above 90°F.
How cold does Yellowstone get in winter?: January is the coldest month, averaging a low of 12°F and a high of 31°F at Mammoth Hot Springs. About 202 nights a year drop to freezing or below.
Does it snow at Yellowstone?: Yes. Mammoth Hot Springs averages 71.5 inches of snow a year, mostly in January, February, March, April, May, October, November and December. Higher ground in the park gets more.
When is the rainy season at Yellowstone?: June is the wettest month on average (1.9 inches of precipitation at Mammoth Hot Springs); the station's annual total is 14.8 inches.
How many hours of daylight does Yellowstone get?: About 15h 32m on June 15 and 8h 50m on December 15 (sunrise 5:36 AM, sunset 9:09 PM in June; 7:52 AM to 4:42 PM in December, America/Denver time).
What is the best month to visit Yellowstone for weather?: By NOAA's normals, average highs sit between 55°F and 85°F in May, June, July, August and September. Of those, May is also well below the park's peak crowds. Weather in the park varies with elevation; this is the Mammoth Hot Springs station.

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