Best Time to Visit Zion National Park: Flash Floods, Trail Heat & What the Data Shows
April and October are the best months for most visitors — 70s temperatures, low flash flood risk, and every major trail open. July is the worst: 101°F averages, monsoon flash floods, and The Narrows closes constantly.
April and October are the best months to visit Zion National Park. Both sit in the sweet spot: warm enough for comfortable hiking (70s), cool enough to avoid heat stroke on exposed trails, and outside the July-September monsoon flash flood window. The Narrows is typically open for wading, Angels Landing permits are easier to snag, and the shuttle system is running.
But Zion isn't like most national parks. The timing question here isn't just about weather comfort — it's about safety. Flash floods have killed visitors in Zion's slot canyons, and summer heat on exposed trails like Angels Landing leads to regular NPS rescues and helicopter evacuations. Those aren't hypotheticals. Seven people died in the September 2015 Keyhole Canyon flood.
I pulled NOAA records from the Springdale weather station (the gateway town at Zion's south entrance) and cross-referenced NPS data on Narrows closures, shuttle schedules, and visitation patterns. Here's what the data shows for each month. You can also check our Zion weather page for monthly averages and historical lookups.
Month-by-Month Zion Weather, Trails & Flash Flood Risk
Temperature data from NOAA records for Springdale, UT (elevation 4,000'). Flash flood risk ratings based on historical monsoon patterns and NPS Narrows closure frequency. Rim temperatures can be 10-20°F cooler.
| Month | Avg High | Avg Low | Flash Flood | Crowds |
|---|---|---|---|---|
| January | 52°F | 29°F | Low | Low |
| February | 57°F | 32°F | Low | Low |
| March | 65°F | 38°F | Low-Moderate | Moderate |
| April | 74°F | 44°F | Low | High |
| May | 85°F | 52°F | Low | Very High |
| June | 97°F | 62°F | Low | Extreme |
| July | 101°F | 68°F | Very High | Extreme |
| August | 99°F | 66°F | Very High | Very High |
| September | 91°F | 57°F | High | High |
| October | 77°F | 45°F | Low | High |
| November | 61°F | 34°F | Low | Low |
| December | 52°F | 28°F | Low | Low |
Temperature: NOAA records for Springdale, UT. Flash flood risk: based on NPS monsoon and Narrows closure data.
January
Cold mornings but surprisingly pleasant by midday. The canyon walls block wind, so 52°F in the sun feels warm. Waterfalls can freeze partially — gorgeous photography. Snow is possible but rare at canyon floor elevation.
February
Similar to January with slightly longer days. Presidents' Day weekend brings a small crowd bump. The Narrows is usually closed due to high water from snowmelt. Good month for solitude.
March
Spring break crowds arrive but March is Zion's rainiest month — 2.1 inches on average. The Narrows may still be closed from snowmelt. Temperatures are perfect for hiking: warm enough for short sleeves by afternoon, cool enough to avoid heat stress.
April
My pick for the best overall month. Highs averaging 74°F are ideal for hiking without heat exhaustion risk. Flash flood risk is low. The Narrows typically opens by mid-April. The catch: it's popular — shuttle lines get long by 9am on weekends.
May
May gets hot quickly. By late May, canyon floor temperatures regularly hit 90°F by early afternoon. Mornings are the window — start hikes by 6-7am. Memorial Day weekend is brutal for crowds. But precipitation is minimal and The Narrows water levels drop.
June
Dangerously hot for exposed hikes. Angels Landing in June means 100°F+ on the exposed ridge with no shade. People get airlifted for heat stroke regularly. The Narrows is the smart play — you're wading in 60°F river water. Start before dawn or skip the strenuous trails.
July
Triple-digit heat and the start of monsoon season. Afternoon thunderstorms roll in 3-4 days per week, and each one brings flash flood risk in the slot canyons. The Narrows closes regularly in July when flows exceed 150 CFS. This is the most dangerous month for flash flooding at Zion.
August
Peak monsoon. August has the most precipitation days of any month (8 on average). Flash flood risk is at its absolute highest — even if skies are clear above you, a storm miles upstream can send a wall of water through a slot canyon. The Narrows closes frequently. If it's open, go early.
September
Monsoon tapers off but isn't gone. Early September is still hot (91°F average high) with flash flood risk. Late September improves dramatically — highs drop to the low 80s, crowds thin after Labor Day, and afternoon storms become less frequent. Late September is the sweet spot.
October
The other best month along with April. Highs of 77°F are ideal for all-day hiking. Flash flood risk drops to low. Fall colors arrive in the canyon — cottonwoods turn gold against the red rock. October is popular (505K visitors in 2024) but not the desperate crush of summer.
November
Underrated. The crowds vanish, the air is crisp, and the light is golden. Highs of 61°F are comfortable for hiking. The Narrows water temperature drops below 50°F — drysuits required if open at all. First frost is typical. Great for photography.
December
Quiet and atmospheric. Snow occasionally dusts the canyon rims while the floor stays dry — one of Zion's most photogenic scenes. Holiday week (Dec 25 - Jan 1) brings a small crowd bump. Short days mean you lose light by 5pm.
Flash Flood Risk at Zion — This Is the Data That Matters
Flash floods are the #1 safety risk at Zion, and most travel guides mention them in one sentence. That's not enough. This is the park where slot canyons funnel water from miles away into narrow passages faster than you can climb out.
The North American Monsoon brings afternoon thunderstorms from mid-July through September. These storms are hyper-localized — it can be clear and sunny at your location while a storm upstream is generating a flood wave heading your way. The NPS closes The Narrows when Virgin River flows exceed 150 cubic feet per second (CFS) or when the National Weather Service issues any flash flood warning.
Highest Risk: July & August
Afternoon monsoon thunderstorms develop 3-5 days per week. The Narrows can close with hours of notice. Slot canyons (Keyhole, Pine Creek, Orderville) are especially dangerous. Seven people died in the September 2015 Keyhole Canyon flash flood. Check NPS conditions the morning of any canyon hike.
Lowest Risk: Oct – June
Outside monsoon season, flash flood risk drops to near zero. March has the most rain (2.1″) but it falls as steady winter rain, not the violent downbursts that cause flash floods. Spring snowmelt raises river levels but predictably, not catastrophically. October through December is the safest window.
Which Month Is Best? Ranked by What You Want
Best Overall
Both offer the golden zone: 70s highs, low flash flood risk, all trails and The Narrows open, shuttle running. April is slightly warmer for Narrows wading. October has better photography light and fall color.
Best for The Narrows
Water levels are manageable, flows below 150 CFS, and the water temperature is tolerable (55-65°F). Summer monsoon months mean frequent closures. Late April works too but the water is cold.
Best for Angels Landing
The exposed chain section bakes in summer — rock surface temps can exceed 110°F. Spring and late fall temps (60-75°F) keep it safe. Permits required year-round. Get the day-before lottery if seasonal lotteries sell out.
Best for Solitude
The shuttle stops running in late November. You can drive the scenic drive yourself. Visitor counts drop 70%+ from peak. Daytime highs of 52-57°F are comfortable with a jacket. Snow on the canyon rims is magical.
Best for Photography
Low-angle winter light paints the canyon walls gold and amber. Snow on red rock is the signature shot. No shuttle means easier tripod setups. Golden hour lasts longer due to canyon wall angles in winter.
Worst Overall
Triple-digit heat, peak flash flood risk, extreme crowds, and The Narrows closes frequently. People get airlifted for heat stroke on Angels Landing. The only upside: late-afternoon thunderstorms create dramatic photography (from a safe distance).
Canyon Floor vs. Rim: The Temperature Split
One thing most guides miss: Zion has a 20°F temperature gap between the canyon floor (4,000' elevation) and the rim (7,000'). When it's 100°F on the Riverside Walk, Observation Point can be 80°F.
This matters for trip planning. If you're visiting in summer, plan rim hikes for midday (when the canyon floor is scorching) and canyon-floor hikes for early morning or evening. The Pa'rus Trail stays shaded longer than most due to its orientation. Angels Landing starts in the canyon and climbs to the rim — you get both temperature zones in one hike, which makes summit arrival at midday in July genuinely dangerous.
Zion Weather Records & Extremes
Canyon floor. Utah's statewide record is 117°F — Zion has matched it.
Rare extreme. Canyon floor averages rarely drop below 25°F even in January.
Per year. Desert climate means sunshine is the default — even in winter.
Virgin River flow rate at which NPS closes The Narrows trail to all hiking.
For Utah's statewide temperature records, see our Utah records page. The hottest temperatures ever recorded in every state puts Zion's heat in perspective against the full national picture.
Frequently Asked Questions
What is the best month to visit Zion National Park?
April and October are the best months to visit Zion National Park. Both offer temperatures in the 70s (ideal for hiking), low flash flood risk, and all major trails open including Angels Landing and The Narrows. April averages a high of 74°F with just 5 precipitation days. October averages 77°F with fall cottonwood colors against the red rock. The main difference: April has warmer Narrows water for wading, while October has better photography light.
Is it too hot to hike Zion in July?
Yes, July is dangerously hot for most Zion hikes. The average high reaches 101°F at canyon floor level, and exposed trails like Angels Landing can exceed 110°F on the rock surface. NPS reports regular heat-related rescues and airlifts during summer months. The Narrows (wading in the Virgin River) is the only safe strenuous activity — but even that closes frequently in July when flash floods push flows above 150 CFS. If you must visit in July, hike only before 8am or after 6pm, carry a gallon of water per person, and avoid Angels Landing entirely.
When is flash flood season at Zion?
Flash flood season at Zion runs from mid-July through September, coinciding with the North American Monsoon. July and August have the highest risk — afternoon thunderstorms develop quickly and can send walls of water through slot canyons even when skies are clear at canyon level. The Narrows closes when Virgin River flows exceed 150 CFS or when the National Weather Service issues a flash flood warning. September's risk decreases but doesn't disappear. Flash floods have killed visitors at Zion — the September 2015 flood killed 7 people in Keyhole Canyon.
What is the best time to hike The Narrows?
Late April through mid-June and late September through October are the best windows for hiking The Narrows. In spring, water levels drop as snowmelt ends, and temperatures are warm enough for comfortable wading. The water is cold (mid-50s°F) but tolerable with canyoneering socks or drysuits. Summer months (July-August) bring frequent monsoon closures. By late October, water temperatures drop below 50°F and the wading becomes genuinely uncomfortable without drysuits. The Narrows typically closes for the winter season in late November when water becomes too cold.
Does it snow at Zion National Park?
Snow is rare at Zion's canyon floor (4,000 feet elevation) but common on the rims and higher trails (7,000 feet). The canyon floor might see 1-3 light snowfalls per winter, usually melting by midday. The rim can accumulate several inches. When it does snow, the contrast of white snow on red sandstone is one of Zion's most photographed scenes. Temperatures at the canyon floor rarely drop below 25°F even in the coldest months — the canyon walls provide thermal insulation.
Data Sources & Methodology
Temperature and precipitation data from NOAA NCEI climate normals for Springdale, UT. Flash flood risk ratings based on NPS Zion weather and climate data, including historical Narrows closure frequency. Visitation statistics from NPS IRMA portal. Angels Landing permit information from NPS.gov. Our site's 139M+ historical weather observations used for Springdale and St. George climate context.
Explore Nearby National Park Weather
Look Up Weather for Your Zion Trip Dates
Search 55+ years of NOAA records for Springdale, St. George, and Cedar City. See what the weather was on your exact travel dates in past years.
Search Weather History