Grand Canyon Weather: Forecasts, Climate & Best Time to Visit

By Jocelyn Pion · Data: National Park Service · ← Complete guide Grand Canyon

The Grand Canyon spans elevations from 2,500 feet at the canyon bottom to 8,400 feet on the North Rim. Those changes create radically different microclimates depending on where you are. The short version. The South Rim has cold, snowy winters and hot, stormy summers. At the canyon bottom, summers are scorching, with highs reaching 117°F, while winters are mild. The summer monsoon, from mid-July through mid-September, is the main rainy season. Conditions can change within hours, so check the forecast before every outing.

For everything related to planning your trip, including entrance fees, lodging, and transportation, our complete Grand Canyon guide covers the essentials.

Grand Canyon Climate Month by Month

The averages below are for the South Rim, at about 7,000 feet. At the canyon bottom, consistently add 20 to 30°F to these temperatures.

The Climate Season by Season

Winter (December to February)

The South Rim regularly gets snow from December through February. Overnight temperatures drop below 19°F and can fall much lower. Trails can be icy, so microspikes or light traction devices are essential. You can find them in park stores. The North Rim is closed to vehicles from mid-October through May, while the South Rim remains accessible year-round. In return, crowds are thin, the low winter light on the snow-covered walls is striking, and lodging rates drop noticeably.

Spring (March to May)

April and May bring very pleasant conditions. Temperatures gradually rise on the South Rim, reaching 72°F in May. At the canyon bottom, it's already hot, at 95°F or higher, and a midday descent requires serious attention to hydration. In March and early April, conditions remain changeable. A sunny morning can turn into a cold shower. Plan to dress in layers.

Summer (June to August)

June is the driest and hottest month before the monsoon, with temperatures around 82°F at the rim and 104 to 113°F at the canyon bottom. Starting in mid-July, the Arizona monsoon settles in. Severe thunderstorms break out almost every afternoon, sometimes with hail. These storms can trigger flash floods in narrow side canyons even when you can't see any rain from where you are. The NPS strongly advises against descending below the rim between 10 a.m. and 4 p.m. from June through August because of the deadly heat risk.

Fall (September to November)

September is still influenced by the monsoon, but storms gradually become less frequent toward the end of the month. October is excellent, with clear skies, mild temperatures on the South Rim, around 63°F during the day, fewer visitors after the summer season, and fall light on the canyon walls. The North Rim closes to vehicles on October 15. In November, snow can return as early as mid-month, and some services, including secondary shuttles and smaller cafeterias, reduce their hours.

Is It Cold at the Grand Canyon? Records and Extremes

It depends entirely on elevation. On the South Rim, record lows hover around -4°F. At the canyon bottom, at Phantom Ranch, 2,500 feet, a winter day can reach 41 to 59°F. The reverse is just as striking in summer. While the rim stays around 86°F, the bottom can reach 117°F. The 20 to 30°F difference between the rims and the canyon bottom holds year-round. The main rainy season is the monsoon, from mid-July through mid-September, bringing severe thunderstorms and a risk of flash floods. Winter also brings precipitation, mostly as snow on the South Rim.

What to Wear Each Season

In winter. Bring a down jacket, warm hat, gloves, and waterproof shoes. Trails can be covered with hard-packed ice, so microspikes or light traction devices are well worth carrying. Camping without winter gear below 19°F is unreasonable.

In spring. Dress in layers. Wear a breathable T-shirt, fleece, and a lightweight waterproof shell. Mornings are cool, while afternoons can be warm or rainy depending on the week.

In summer. Wear lightweight, breathable clothing, a wide-brimmed hat, and sunglasses on the rims. If you're descending into the canyon, add sturdy hiking shoes with ankle support for rocky, unstable terrain, at least 2 liters of water per hour of hiking, and salty snacks to replace what you lose through sweat. Start down early and hike back up before 10 a.m. or after 4 p.m.

In fall. Follow the same approach as in spring. Add a warm layer starting in mid-October, since mornings cool off quickly at 6,600 feet.

Alerts and Conditions to Watch

Flash floods. During the monsoon, a thunderstorm on the plateau upstream can trigger a flood in a corridor where the sky is still clear. Before any descent, check National Weather Service forecasts for the Flagstaff/Grand Canyon area. If the sky darkens upstream, leave the canyon bottom immediately.

Extreme heat at the canyon bottom. The NPS imposes access restrictions on inner-canyon trails once temperatures reach 100°F. Rangers may turn away hikers who don't have enough water and food. People die from heat illness and dehydration every summer, so this warning is not merely symbolic.

Roads and winter closures. Heavy snowfall can lead to temporary closures on some rim roads. Check conditions on the park's official website before setting out, especially in December and January.

For trails that work in each season, elevation gains, and seasonal safety recommendations, see Grand Canyon hikes.

Frequently Asked Questions