May in Great Smoky Mountains National Park is a good month: highs around 77°F, lows around 52°F. Crowds: busy — #5 busiest of the park's 12 months. Lush green; firefly-lottery applications open (for June). The editorial best window here is June & October. You get about 14h 03m of daylight. To finish Alum Cave Trail (2h 5m) before dark, leave the trailhead by about 6:26 PM.
Month data reviewed · how we check this
| Verdict | Good A solid visit with a caveat — usually crowds or heat. |
|---|---|
| Temps °F | 77° high / 52° low |
| Crowds | busy · #5 busiest of the park's 12 months |
| What May is like | Lush green; firefly-lottery applications open (for June) |
| Best window (whole year) | June & October |
| Peak crowds (whole year) | Jun–Aug, 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 (EDT)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 77°F. TRAILS WE HAVE NOT MEASURED ARE LEFT OUT RATHER THAN GUESSED
WHAT MAY ASKS OF YOU HEREGreat Smoky Mountains National Park in June — Best window, highs around 84°F, crowds: peak crowds (synchronous fireflies light up early june (lottery entry)).
Our verdict for May is "Good". A solid visit with a caveat — usually crowds or heat. Expect highs around 77°F and lows around 52°F, with crowds at the "busy" 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 June & October, and the peak-crowd months are Jun–Aug, Oct. May itself we rate "Good".
June we rate "Best window" against "Good" for May, with highs around 84°F and crowds at the "peak crowds" level.
About 14h 03m on May 15: the sun rises around 6:29 AM and sets around 8:31 PM local park time (EDT). Computed from the park's own coordinates, so it is the light you actually get at the trailhead, not the nearest city's.
Alum Cave Trail takes about 2h 5m of walking, so on May 15 you would need to leave the trailhead by about 6:26 PM to finish before dark — the sun sets around 8:31 PM local park time (EDT). 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.
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