May in Arches National Park is a best window month: highs around 82°F, lows around 51°F. Crowds: peak crowds — #1 busiest of the park's 12 months. Fiery Furnace ranger hikes run May–September; Memorial Day is a peak. The editorial best window here is April–May & September–October. You get about 14h 17m of daylight. To finish Devils Garden Trail (full loop) (2h 45m) before dark, leave the trailhead by about 5:37 PM.
Month data reviewed · how we check this
| Verdict | Best window The editorial pick — weather, access and experience line up. |
|---|---|
| Temps °F | 82° high / 51° low |
| Crowds | peak crowds · #1 busiest of the park's 12 months |
| What May is like | Fiery Furnace ranger hikes run May–September; Memorial Day is a peak |
| Best window (whole year) | April–May & September–October |
| Peak crowds (whole year) | Apr–May, Sep–Oct |
CROWDS: RELATIVE SEASONALITY FROM NPS VISITATION STATISTICS · TEMPS: APPROXIMATE NOAA NORMALS AT MAIN VISITOR ELEVATION — HIGH COUNTRY RUNS 10–20°F COLDER
DAYLIGHT ON MAY 15 · LOCAL PARK TIME (MDT)COMPUTED FROM THE PARK'S OWN COORDINATES FOR THE 15TH — THE MIDDLE OF THE MONTH STANDS FOR IT, AS IT DOES FOR CLIMATE NORMALS. WITHIN A MONTH THESE TIMES SHIFT BY UP TO AN HOUR
LEAVE THE TRAILHEAD BY — TO FINISH BEFORE DARK ON MAY 15WALKING TIMES ESTIMATED FROM EACH TRAIL'S MEASURED DISTANCE AND ELEVATION GAIN — A PLANNING FIGURE, NOT A PACE. ADD YOUR OWN MARGIN FOR PHOTOS, REST AND CROWDS. WATER AT THE COOL-WEATHER RATE, BECAUSE THIS MONTH AVERAGES 82°F. TRAILS WE HAVE NOT MEASURED ARE LEFT OUT RATHER THAN GUESSED
WHAT MAY ASKS OF YOU HEREArches National Park in June — Tough, highs around 93°F, crowds: busy (heat starts deciding the day — walk before 9am or after 5pm).
Our verdict for May is "Best window". The editorial pick — weather, access and experience line up. Expect highs around 82°F and lows around 51°F, with crowds at the "peak crowds" level. Temperatures are approximate NOAA normals at the main visitor elevation; crowd levels follow published NPS visitation statistics.
Across the full 12-month review, the best window is April–May & September–October, and the peak-crowd months are Apr–May, Sep–Oct. May itself we rate "Best window".
June we rate "Tough" against "Best window" for May, with highs around 93°F and crowds at the "busy" level.
About 14h 17m on May 15: the sun rises around 6:06 AM and sets around 8:23 PM local park time (MDT). Computed from the park's own coordinates, so it is the light you actually get at the trailhead, not the nearest city's.
Devils Garden Trail (full loop) takes about 2h 45m of walking, so on May 15 you would need to leave the trailhead by about 5:37 PM to finish before dark — the sun sets around 8:23 PM local park time (MDT). Walking times are estimated from each trail's measured distance and elevation gain, so treat them as a planning figure and add your own margin for photos, rest and crowds.
Get a heads-up before timed-entry and lottery windows open — plus new guides for the parks you care about.
FREE · NO SPAM · UNSUBSCRIBE IN ONE TAP
© 2026 StayNear National Parks · About · Methodology · Privacy · Terms · Affiliate disclosure · Refunds