Glacier National Park Weather by Month (30°F–82°F Temperature Guide)
Average temperatures, precipitation, trail conditions, and what to expect at Glacier every month of the year.
Last verified against official NPS sources
Glacier National Park's weather varies dramatically by season: July and August deliver sunny 80°F days with full trail access, while January averages highs near 30°F with 200+ inches of annual snowpack. Planning around weather is essential — the difference between late June and early July can mean having access to Logan Pass or not.
This guide covers average temperatures, precipitation, trail conditions, and what to expect at Glacier National Park every month of the year, per NPS.gov and long-term climate records.
Monthly Weather Overview
The table below shows climate averages for West Glacier (elevation 3,154 ft), the park's primary west entrance. High-elevation areas like Logan Pass (6,646 ft) run 15–20°F cooler and receive significantly more snowfall, per NPS.gov. West Glacier is wetter than the east side, while the east side is generally drier and windier; conditions vary substantially by elevation and location.
| Month | Avg High | Avg Low | Precip | Conditions Summary |
|---|---|---|---|---|
| January | 30°F / -1°C | 16°F / -9°C | 3.5 in | Snow, quiet, roads limited to lower areas |
| February | 35°F / 2°C | 18°F / -8°C | 2.8 in | Cold, snowy, snowshoe and ski season |
| March | 44°F / 7°C | 23°F / -5°C | 2.0 in | Variable — can snow heavily or warm quickly |
| April | 54°F / 12°C | 30°F / -1°C | 1.6 in | Mild, lower trails clearing, GTSR opens to bikes |
| May | 63°F / 17°C | 37°F / 3°C | 1.9 in | Warm, wildflowers at lower elevations, waterfalls peak |
| June | 71°F / 22°C | 44°F / 7°C | 2.5 in | Rainiest month, GTSR typically opens to Logan Pass |
| July | 81°F / 27°C | 49°F / 9°C | 1.5 in | Peak season, most trails open, mostly clear |
| August | 82°F / 28°C | 49°F / 9°C | 1.2 in | Hottest, driest month — wildfire smoke possible |
| September | 70°F / 21°C | 38°F / 3°C | 1.5 in | Excellent conditions, crowds drop sharply |
| October | 56°F / 13°C | 30°F / -1°C | 1.8 in | Larch color peak, first snowstorms mid-month |
| November | 40°F / 4°C | 24°F / -4°C | 2.3 in | Winter arrives, most facilities closed |
| December | 32°F / 0°C | 17°F / -8°C | 3.2 in | Deep winter, cross-country skiing, very quiet |
West Glacier climate averages; park conditions vary substantially by elevation and side of the Continental Divide.
Winter: December–February
December through February is Glacier's coldest and quietest period. Valley temperatures average highs between 30–35°F, while Logan Pass can see sub-zero temperatures with wind chill. The park's average snowpack is approximately 16 feet, with the heaviest snowfall occurring October through March, per NPS.gov.
The Going-to-the-Sun Road from West Glacier to Lake McDonald Lodge is plowed and open year-round when weather permits. The unplowed section beyond Lake McDonald Lodge is used for skiing and snowshoeing. The park remains accessible year-round, but most roads, lodges, campgrounds, and visitor facilities close or operate on limited winter schedules. The Apgar–McDonald Creek corridor and lower Lake McDonald trails remain accessible on many winter days, depending on conditions.
Crowds are minimal. Most lodges, campgrounds, and visitor facilities close by late fall. The Apgar Visitor Center operates limited weekend hours only. For winter visitors, this season offers total solitude and a dramatically different landscape — deep snow, frozen lakes, and wildlife tracks that are impossible to find in summer.
Spring: March–May
Spring is Glacier's most unpredictable season. March can still deliver blizzards with overnight lows in the teens, while May afternoons regularly reach the mid-60s°F. The Continental Divide position means the park catches weather systems from both the Pacific and the Great Plains — pack snow gear, rain gear, and sunscreen for any spring visit.
Lower-elevation trails at Lake McDonald Valley, Two Medicine, and St. Mary may begin clearing by mid-April, but timing varies by trail and year. By May, the park's waterfalls are at peak volume from snowmelt, and wildflowers emerge at lower elevations. The GTSR opens to bicyclists on changing segments before vehicles are allowed; timing and access depend on current conditions, per NPS.gov.
May is one of the best months for wildflower viewing at lower elevations. Campgrounds and most lodges open in late May, crowds are a fraction of summer levels, and the park feels alive without the July pressure.
Summer: June–August
Summer is peak season for both weather and crowds. July and August deliver the best conditions: average highs in the low 80s°F, mostly clear skies, and most trails in the park accessible, though snow, fire, wildlife, construction, or other temporary closures can affect conditions. The full 50-mile Going-to-the-Sun Road is typically open by early July, per NPS.gov.
June is the rainiest month, with frequent afternoon thunderstorms at higher elevations. Mornings are cool (40s°F) and afternoons warm (~71°F). Snowfields still cling to high peaks, waterfalls are thundering from snowmelt, and mid-elevation wildflowers are near peak bloom. Logan Pass usually opens sometime in mid-to-late June, though exact dates vary each year.
July is the clearest and most reliably warm month. Average highs hit 81°F, occasional hot days reach 90°F, and the park is in full operation. Glacier does not require a vehicle reservation in 2026. From July 1 through September 7, Logan Pass uses a three-hour parking limit, and the park shuttle operates with ticketing and capacity controls.
August is nearly identical to July in temperature (highs ~82°F) but carries one significant caveat: wildfire smoke. It is historically the driest month in the park, which increases wildfire risk across the Northern Rockies. In some years, smoke can reduce visibility and degrade air quality for days to weeks. In smoke-free years, August is exceptional. Check AirNow.gov before finalizing late-summer plans.
Fall: September–November
September is widely considered Glacier's best month. Crowds drop sharply after Labor Day, temperatures are ideal for hiking (highs ~70°F), wildfire smoke may improve but is not guaranteed to have cleared, and grizzly bears are hyperactive — gorging on berries and huckleberries before hibernation. Glacier has no vehicle reservation requirement in 2026, and the Logan Pass three-hour parking limit ends after September 7.
Late September brings the park's most spectacular seasonal event: western larch trees turn golden. These rare deciduous conifers — which drop their needles each fall — glow bright yellow against dark evergreens at Many Glacier, Two Medicine, and the North Fork Valley. Peak color typically occurs in the last week of September and first week of October, though it varies by year and elevation.
October begins with some of the best conditions of the year — larch at or near peak, comfortable hiking temperatures (highs mid-50s°F), and no crowds. The average first snowfall date typically falls in mid-October at lower elevations; higher elevations such as Logan Pass can receive early snow and retain persistent snowpack much earlier. The Going-to-the-Sun Road typically closes around the third Monday of October but may close earlier due to winter weather, per NPS.gov. Most lodges and campgrounds close for the season. Late October requires full flexibility — snow can end access without warning.
November transitions fully into winter. Temperatures drop to the 20s°F overnight, services shutter, and visitor volume falls to near-zero. The park remains open for prepared winter travelers, but this is not a casual shoulder-season visit.
Best Time to Visit Glacier National Park
The right month depends on your priorities. Each season offers a distinct experience — and each has trade-offs.
For most first-time visitors, late August through mid-September delivers the best blend of weather, full access, and reasonable crowds. The Logan Pass three-hour parking limit ends after September 7, smoke risk generally decreases from its August peak, and trail conditions can remain excellent into October when weather allows.
| Priority | Best Months | Why |
|---|---|---|
| All trails + GTSR access | July–September | Full road and trail access, best weather window |
| Peak wildflowers | Late May–Early July | Lower elevations first, alpine meadows by July |
| Larch fall color | Late September–Early October | 1–2 week peak, highly weather-dependent |
| Fewest crowds | October, April–May | Shoulder season — facilities open, access good |
| Wildlife viewing | September–October | Bears pre-hibernation; mountain goats at Logan Pass |
| Photography | September, Late May | Golden light, minimal haze, dramatic skies |
| Budget travel | April–May, October | Lower lodging rates, open campsites |
| Winter adventure | January–February | Snowshoeing, cross-country skiing, total solitude |
What to Pack by Season
Glacier's weather can shift rapidly at any elevation. Even on warm summer days, Logan Pass (6,646 ft) typically runs 15–20°F cooler than the Apgar Valley. The NPS recommends the 10 Essentials on all hikes, per NPS.gov. Bear spray is recommended on bear-country trails; carry it accessibly and know how to use it.
| Season | Essential Gear | Key Notes |
|---|---|---|
| Summer (June–Aug) | Rain jacket, insulating mid-layer, sun protection, bear spray | Afternoon thunderstorms common; Logan Pass 15–20°F cooler than valley |
| Fall (Sep–Oct) | Insulated jacket, waterproof boots, traction devices (late Oct) | Early snowfall possible above 5,000 ft by late September |
| Spring (Mar–May) | Waterproof everything, gaiters, microspikes | Postholing through snow common on mid-elevation trails in April |
| Winter (Nov–Feb) | Snowshoes or skis, avalanche awareness gear, warm base layers | Register with rangers for any backcountry winter travel |
Common Questions
What is the best month to visit Glacier National Park?
September is considered the best overall month by experienced visitors. Crowds drop sharply after Labor Day, all trails remain open, temperatures are comfortable (highs 60–70°F), wildfire smoke may have cleared, and bears are highly visible before hibernation. Late September also brings peak western larch color at Many Glacier and Two Medicine.
How cold does Glacier National Park get in winter?
Valley temperatures at West Glacier (~3,154 ft) average highs of 30–35°F and lows of 16–18°F in January and February. Logan Pass (6,646 ft) can see temperatures well below 0°F with wind chill. The park's east side experiences some of Montana's strongest winds in winter — downslope winds of 50 mph or more, and sometimes 100 mph, are possible at St. Mary and Many Glacier.
When does the Going-to-the-Sun Road fully open?
The full GTSR opening to Logan Pass typically occurs between mid-June and early July, depending on annual snowpack. In heavy snow years, the opening can be delayed into July. Lower sections (Apgar to Avalanche Creek) open to bicyclists on changing segments before vehicles are allowed. Always check current conditions at nps.gov/glac before planning a Logan Pass visit.
Does Glacier National Park get wildfire smoke?
Yes. August carries the highest smoke risk — it is the driest month and peak of the regional fire season in the Northern Rockies. In some years, smoke significantly reduces visibility for days to weeks. September often sees improvement as fall moisture arrives, but smoke can persist. Check AirNow.gov for real-time air quality forecasts before visiting in late summer.
Is Glacier National Park open in winter?
Yes. The park is open 24/7 year-round, per NPS.gov. The private-vehicle entrance fee is $25 from November 1 through April 30; self-registration instructions are posted if an entrance station is unstaffed. Most roads close beyond lower parking areas, and the majority of lodges, campgrounds, and visitor facilities close from late fall through spring. Winter access is by foot, snowshoes, or cross-country skis.
What is the weather like in Glacier National Park in June?
June is Glacier's rainiest month, with frequent afternoon thunderstorms and average highs around 71°F. Mornings are cool (mid-40s°F) and higher elevations remain snowy. Mid-elevation wildflowers are near peak bloom. The GTSR typically opens to Logan Pass in mid-to-late June, though early June access is often limited to the lower valley sections below Avalanche Creek.
What is the average first snowfall date in Glacier National Park?
There is no single park-wide average first snowfall date because snowfall varies sharply by elevation and location. Lower elevations such as West Glacier commonly see their first snow in the fall, around mid-October, while Logan Pass and other high elevations can receive early snow much sooner and retain persistent snowpack. A first dusting is not the same as measurable accumulation or lasting trail coverage; check current NPS conditions for the location and date of your visit.
What is Glacier National Park weather like in September?
September at West Glacier averages a high near 70°F and a low near 38°F, with relatively low precipitation in the monthly table above. Days are usually favorable for hiking, but alpine snow, frost, wind, wildfire smoke, and sudden weather changes remain possible. Road and trail access can change as fall progresses, so check current NPS conditions.
Sources & Further Reading
- NPS — Glacier weather — National Park Service
- NPS — Glacier spring conditions — National Park Service
- NPS — Glacier current conditions — National Park Service
- NPS — Glacier operating hours and seasons — National Park Service
- NPS — Glacier safety — National Park Service
- NPS — Visiting Logan Pass in 2026 — National Park Service
- NPS — Visiting in Winter — National Park Service
- NPS — Fees & Passes — National Park Service
