Yellowstone Weather: Forecast and Month-by-Month Averages
Live forecasts from the National Weather Service. Monthly averages are NOAA 1991-2020 climate normals. Check the NPS alerts page for road and trail closures.
In shortYellowstone sits mostly on a high plateau, from about 5,300 ft near Gardiner to over 11,000 ft on the peaks, with most roads and villages between 6,200 and 8,900 ft. The table is for Mammoth Hot Springs (about 6,200 ft), the lowest and mildest developed area; Old Faithful, Canyon and Yellowstone Lake are higher and typically several degrees colder and snowier. Winters are long and very cold, summers are short and mild with afternoon thunderstorms, and snow is possible in any month at higher elevations.
Yellowstone forecast by area
Weather changes a lot with elevation here, so check the forecast for where you are actually going. Each forecast covers the National Weather Service grid square around that spot.
Mammoth Hot Springs (North Entrance area) 6,200 ft
The table's station. Lowest, driest, mildest developed area; the road from Gardiner through Mammoth to Cooke City is the only one open to cars all winter.
The live 7-day forecast loads here. You can also open the National Weather Service forecast for Mammoth Hot Springs (North Entrance area).
Yellowstone Lake (Lake Village / Fishing Bridge) 7,782 ft
NPS averages run about 7-10°F colder than Mammoth; winter lows near 0°F and summer nights in the low 40s or 30s.
The live 7-day forecast loads here. You can also open the National Weather Service forecast for Yellowstone Lake (Lake Village / Fishing Bridge).
Dunraven Pass (Grand Loop, Tower-Canyon) 8,859 ft
Highest point on the Grand Loop; snow possible any month, and the road usually closes in mid-October and is among the last to open in late May.
The live 7-day forecast loads here. You can also open the National Weather Service forecast for Dunraven Pass (Grand Loop, Tower-Canyon).
Average weather in Yellowstone by month
| Month | Avg high | Avg low | Precipitation | Snowfall |
|---|---|---|---|---|
| January | 31°F | 12°F | 0.9 in | 11.5 in |
| February | 34°F | 12°F | 0.8 in | 11.5 in |
| March | 42°F | 19°F | 1.1 in | 10.9 in |
| April | 50°F | 26°F | 1.4 in | 7.8 in |
| May | 60°F | 35°F | 1.8 in | 1.7 in |
| June | 70°F | 42°F | 1.9 in | 0.3 in |
| July | 81°F | 48°F | 1.3 in | 0.0 in |
| August | 80°F | 46°F | 1.1 in | 0.0 in |
| September | 69°F | 39°F | 1.2 in | 0.6 in |
| October | 54°F | 29°F | 1.3 in | 4.7 in |
| November | 39°F | 19°F | 1.1 in | 9.9 in |
| December | 30°F | 12°F | 0.9 in | 12.6 in |
These are long-term averages at one station. Higher areas of the park are colder, and any single year can be much warmer, colder, wetter or drier.
Yellowstone weather month by month
Yellowstone in January
31°F / 12°F. Deep winter, with highs near 31°F at Mammoth and colder elsewhere. Most park roads are closed to cars; the interior is reached only by commercially guided snowcoach or snowmobile, and the North-to-Northeast Entrance road is the only one open to regular vehicles.
Yellowstone in February
34°F / 12°F. Still fully winter, with frequent snow and subzero nights. Oversnow travel continues, weather permitting, and wildlife watching in the Lamar Valley via the year-round road is a highlight.
Yellowstone in March
42°F / 19°F. Winter lingers with snow in many areas. Oversnow travel usually ends in mid-March as spring plowing begins, so the interior is largely closed to all visitors for several weeks.
Yellowstone in April
50°F / 26°F. Roads begin opening to regular vehicles in mid-April, weather permitting, starting with the west and north sections of the Grand Loop. Expect snowstorms, slushy roads and many closed facilities.
Yellowstone in May
60°F / 35°F. Lower areas thaw while snow remains at higher elevations. Most roads, including Dunraven Pass and the Beartooth Highway outside the Northeast Entrance, typically open by Memorial Day weekend, but late storms can close roads briefly.
Yellowstone in June
70°F / 42°F. Variable, with highs around 70°F at Mammoth but snow still possible at high elevations. Rivers run high with snowmelt, waterfalls peak, and crowds build.
Yellowstone in July
81°F / 48°F. The warmest month (highs near 81°F at Mammoth, cooler at Lake and Old Faithful), with frequent afternoon thunderstorms. Peak crowds; nights can still drop into the 40s or lower.
Yellowstone in August
80°F / 46°F. Generally warm and very dry with occasional thunderstorms; wildfire smoke and haze are possible. Busy, with cool mornings at higher elevations.
Yellowstone in September
69°F / 39°F. Pleasant days and cool nights, with early snow possible at higher elevations. Crowds thin after Labor Day and elk rut activity peaks.
Yellowstone in October
54°F / 29°F. Colder, with snow increasingly common. Dunraven Pass and the Beartooth Highway typically close in mid-October, and other roads can close temporarily for storms; many lodges and services shut down.
Yellowstone in November
39°F / 19°F. Winter storms and freezing temperatures. Most park roads close to regular vehicles in early November; only the Gardiner-Mammoth-Cooke City road stays open.
Yellowstone in December
30°F / 12°F. Very cold with heavy snow. The winter season opens in mid-to-late December with guided snowcoach and snowmobile trips, weather permitting; the North-to-Northeast road remains the only one open to cars.
Weather hazards to plan for
- Sudden snowstorms and whiteouts any month at high elevations, including Dunraven Pass and Sylvan Pass, can close roads with little notice.
- Afternoon lightning storms in July and August on exposed ridges, open valleys and lakeshores.
- Extreme winter cold, with nights well below 0°F at Lake, Old Faithful and West Yellowstone; frostbite and hypothermia risk for oversnow travelers.
- Cold water: Yellowstone Lake stays very cold year-round, and capsized boaters can quickly become hypothermic even in summer.
- Wildfire smoke and haze in mid-to-late summer, plus icy, snow-packed roads in spring and fall shoulder seasons.
Yellowstone weather questions
What is the weather like in Yellowstone in October?
October is cold and changeable: Mammoth averages highs around 54°F and lows around 29°F, and higher areas are colder. Snow is increasingly common, and Dunraven Pass and the Beartooth Highway typically close in mid-October.
Does it snow in Yellowstone in summer?
Yes, snow is possible in any month at higher elevations, especially in June and September. At Mammoth, summer snowfall averages near zero, but passes such as Dunraven (8,859 ft) can see snow.
How cold does it get at night in Yellowstone in summer?
Even in July, average lows are about 48°F at Mammoth and in the low 40s at Yellowstone Lake, and some nights fall near freezing at higher elevations. Bring warm layers for evenings and early mornings.
When are Yellowstone's roads open?
Roads typically begin opening to regular vehicles in mid-April and are all open by Memorial Day weekend, weather permitting; most close again in early November. The road from the North Entrance to Cooke City via Tower Junction is the only one open to regular vehicles year-round.
What is the best month for weather in Yellowstone?
July and August are the warmest and most reliable, with highs around 80°F at Mammoth but frequent afternoon thunderstorms. September offers pleasant days, cool nights and fewer crowds, with a chance of early snow up high.
Yellowstone planning guides
- Best Time to Visit Yellowstone National ParkWhen to visit Yellowstone, month by month: road opening and closing dates, crowds, weather, wildlife timing and what is open in each season.
- How Many Days Do You Need in Yellowstone?How many days to spend in Yellowstone, with 1-, 2-, 3- and 4-day itineraries by area, NPS drive times around the Grand Loop and where to base yourself.
- Best Hikes in Yellowstone National ParkThe best day hikes in Yellowstone, from the Grand Prismatic Overlook to Mount Washburn and Avalanche Peak, with NPS distances, elevation gain and 2026 closures.
- Camping in Yellowstone National Park: Campgrounds, Reservations and TipsAll 11 Yellowstone campgrounds with 2026 dates, fees and RV limits, how six-month reservations work, the 2027 move to Recreation.gov and backcountry permits.