Mt. Lemmon Elevation: How High Is It?

Mount Lemmon tops out at 9,171 feet (2,795 m) above sea level, the highest point in the Santa Catalina Mountains and the high point of Pima County. Tucson, down in the valley, sits at 2,389 feet. That means a drive of about 27 miles lifts you 6,782 feet — roughly a mile and a quarter of vertical gain — and it is the reason a summer afternoon up here can feel like a completely different state.

The Numbers Behind Mt. Lemmon Elevation

• Summit elevation: 9,171 feet (2,795 m), per the National Geodetic Survey, on the North American Vertical Datum of 1988. You may still see 9,157 feet quoted online — that is the older USGS figure still floating around, and the surveyors' number today is 9,171.
• Tucson elevation: 2,389 feet, the official figure for the city.
• Total climb: 6,782 feet of gain from the Tucson valley to the summit, over 27.2 miles of the Catalina Highway (also signed as the Sky Island Parkway, a National Scenic Byway).
• Average grade: roughly 250 feet of climb for every mile you drive up.
• Summerhaven elevation: about 8,000 feet — sources range from 7,764 feet at the census point to 8,200 feet, depending on where on the mountain you stand. Just over 1,000 feet below the summit.
• Highest point in the Santa Catalinas: Mount Lemmon. The only taller peak near Tucson is Mount Wrightson at 9,452 feet, over in the Santa Rita Mountains to the south.

What the Elevation Does to the Weather

Temperature drops roughly 3 to 5 degrees Fahrenheit for every 1,000 feet you climb. Multiply that by 5,600 feet between Tucson and Summerhaven and you get the single best-known fact about this mountain: Summerhaven generally runs about 20 to 30 degrees cooler than Tucson on a summer afternoon. A 103-degree day downtown is often a 75 to 80 degree day here.

Elevation also decides what grows. In those 27 miles the road climbs through five life zones — Sonoran Desert scrub at the bottom, then desert grassland and chaparral, oak woodland, ponderosa pine forest, and finally a mixed conifer and aspen forest at the top that includes Douglas fir, white fir, corkbark fir and Engelmann spruce. It is one of the steepest ecological gradients in North America, and it exists purely because of the climb. You can see the whole sequence photographed on our Mt. Lemmon flowers, plants and trees guide.

And in winter, elevation means snow. The Ski Valley base sits at about 8,200 feet, making it the southernmost ski area in the United States — an hour from cactus country.

Elevation Along the Drive

• Tucson valley floor — 2,389 ft. Saguaros, palo verde, 100-degree summers.
• Molino Basin — the road's first big step up into oak woodland, where the saguaros thin out.
• Windy Point — about 6,600 ft. Hoodoos and cliff-edge views of the whole Tucson basin. The spot most people stop for the photo.
• Rose Canyon Lake — 7,000 ft. A six-acre stocked trout lake ringed by ponderosa pines.
• Summerhaven — about 8,000 ft, and where our cabins are. Cooked breakfast, a general store and pines in every direction.
• Ski Valley base — about 8,200 ft, with the lifts running up toward the summit.
• Mt. Lemmon summit — 9,171 ft. Sky Island Parkway ends at a mountaintop in the Coronado National Forest with the University of Arizona's SkyCenter observatory nearby.

Want the stops in order with drive times? Our Catalina Highway scenic drive guide and our guide to Mt. Lemmon's overlooks cover them in more detail.

What 9,171 Feet Feels Like

You are not going to get altitude sickness at 9,171 feet — that is a concern people run into above 10,000 feet, and mostly higher still. But you will notice the difference in a few practical ways:

• The air is thinner. Air pressure at the summit is around 70 percent of sea level, so a steep trail feels harder than the same walk would at home, especially if you are visiting from a low elevation.
• The sun is stronger. There is less atmosphere above you to filter UV, so sunburn arrives faster up here than in Tucson — even on a cool, cloudy day. Bring the hat and sunscreen.
• You dry out faster. The combination of elevation, low humidity and wind means you should drink more water than feels necessary.
• It cools off after dark. That same elevation drop that keeps summer comfortable means temperatures fall fast in the evening, all year. A jacket in the car is never a bad idea.
• If you have a heart or lung condition, take the climb and the walking slowly and check with your doctor before a big hike.

How Mt. Lemmon's Height Compares

For scale, 9,171 feet is higher than Mount Mitchell in North Carolina at 6,684 feet, which is the highest point in the entire eastern United States. It is taller than the highest point in Texas, the highest point in South Dakota, and higher than the top of any state east of the Rocky Mountains. It is not the tallest thing in Arizona — that is Humphreys Peak at 12,637 feet above Flagstaff — but it is a mile and a quarter of climbing you can do in a car in about an hour, and that is the part visitors find hard to believe.

One more bit of context for the state as a whole: Arizona is one of the most mountainous states in the country, with roughly 210 named mountain ranges. Only Nevada has more, at 314. The Santa Catalinas are one of those ranges, and Mt. Lemmon is their high point.

Mt. Lemmon Elevation in Photos

Planning around the elevation: the mountain makes its own weather, so check conditions before you drive up. Our Mt. Lemmon weather page carries the forecast and live cameras, and our road conditions guide covers closures, chain requirements and the road hotline. In winter especially, the same elevation that keeps summer cool can close the highway above a certain point — do not assume the top is open because the bottom is clear.

Mt. Lemmon Elevation: Frequently Asked Questions

How high is Mount Lemmon?

The summit is 9,171 feet (2,795 m) above sea level, the highest point in the Santa Catalina Mountains and the highest point in Pima County. It is measured on the North American Vertical Datum of 1988; older sources that list 9,157 feet are using the superseded USGS figure.

How much elevation do you gain driving up from Tucson?

About 6,780 feet. Tucson sits at 2,389 feet and the summit is 9,171 feet, so the 27-mile Catalina Highway climb is roughly a mile and a quarter of vertical gain, at an average of about 250 feet per mile.

How high is Summerhaven, Arizona?

About 8,000 feet, a little over 1,000 feet below the summit — which is why our cabins in Summerhaven stay so much cooler than Tucson in summer and see real snow in winter.

Is Mt. Lemmon higher than mountains in the eastern United States?

Yes. At 9,171 feet it is higher than Mount Mitchell in North Carolina (6,684 feet), which is the highest point east of the Mississippi River, and higher than the highest point of any state east of the Rocky Mountains.

Does the elevation affect visitors?

At 9,171 feet you are below the range where altitude sickness is usually a problem, so most visitors feel fine. You may notice the thinner air on a steep trail, and you will burn faster in the sun and dry out faster than you would in Tucson. Drink water, wear sunscreen, and take big hikes at an easy pace. Anyone with a heart or lung condition should check with a doctor first.

When does it snow on Mt. Lemmon?

Winter storms typically bring snow between December and March, and the Ski Valley base at 8,200 feet is the southernmost ski area in the United States. Snow can also fall in late fall and early spring. Check our road conditions guide before driving up during or after a storm.