Lemhi Pass is a mountain pass in Lemhi County, Idaho. The nearest town is Salmon, about 42 km (26 mi) away (Lemhi Pass lies ESE of town). It is listed on the National Register of Historic Places.
Lemhi Pass is a high mountain pass in the Beaverhead Mountains, part of the Bitterroot Range in the Rocky Mountains and within Salmon-Challis National Forest. The pass lies on the Montana-Idaho border on the Continental Divide, at an elevation of 7,373 feet (2,247 m) above sea level. It is accessed via Lemhi Pass Road in Montana, and the Lewis and Clark Highway in Idaho, both gravel roads. Warm Springs Road, which roughly follows the divide in Montana, passes just west of the pass's high point.From the Wikipedia article “Lemhi Pass”, licensed under CC BY-SA 4.0.
Sunrise & sunset directions
At Lemhi Pass the sunrise point swings a long way through the year: about 55° (NE) at the June solstice and 123° (ESE) in late December. Sunset moves from 305° (NW) in June to 237° (WSW) in December, and the midday sun climbs to 68° in summer but only 22° in winter.
| Date | Sunrise | Azimuth | Sunset | Azimuth | Noon sun | Daylight |
|---|---|---|---|---|---|---|
| March equinox (Mar 20) | 7:38 AM | 90° E | 7:46 PM | 271° W | 45° | 12h 09m |
| June solstice (Jun 21) | 5:48 AM | 55° NE | 9:25 PM | 305° NW | 68° | 15h 37m |
| September equinox (Sep 22) | 7:22 AM | 89° E | 7:33 PM | 271° W | 45° | 12h 11m |
| December solstice (Dec 21) | 8:10 AM | 123° ESE | 4:56 PM | 237° WSW | 22° | 8h 46m |
Azimuth is measured clockwise from true north (90° = east, 270° = west). Computed for 2026; values change by less than a degree from year to year.
Golden hour & blue hour by month
Mountain passes sit above valleys, so they reward sunrise and sunset with layered ridges, valley fog and long shadows.
| Month (15th) | Blue hour starts | Sunrise | Golden hour ends | Golden hour starts | Sunset | Blue hour ends | Daylight |
|---|---|---|---|---|---|---|---|
| January | 7:36 AM | 8:09 AM | 8:56 AM | 4:32 PM | 5:19 PM | 5:51 PM | 9h 10m |
| February | 7:05 AM | 7:36 AM | 8:17 AM | 5:21 PM | 6:02 PM | 6:32 PM | 10h 26m |
| March | 7:18 AM | 7:47 AM | 8:26 AM | 7:01 PM | 7:40 PM | 8:09 PM | 11h 53m |
| April | 6:19 AM | 6:50 AM | 7:29 AM | 7:40 PM | 8:19 PM | 8:50 PM | 13h 29m |
| May | 5:31 AM | 6:06 AM | 6:48 AM | 8:14 PM | 8:56 PM | 9:31 PM | 14h 51m |
| June | 5:10 AM | 5:47 AM | 6:33 AM | 8:38 PM | 9:23 PM | 10:00 PM | 15h 35m |
| July | 5:26 AM | 6:02 AM | 6:46 AM | 8:35 PM | 9:19 PM | 9:54 PM | 15h 16m |
| August | 6:05 AM | 6:36 AM | 7:17 AM | 8:01 PM | 8:42 PM | 9:14 PM | 14h 05m |
| September | 6:44 AM | 7:13 AM | 7:52 AM | 7:08 PM | 7:46 PM | 8:16 PM | 12h 33m |
| October | 7:20 AM | 7:50 AM | 8:30 AM | 6:10 PM | 6:50 PM | 7:20 PM | 11h 00m |
| November | 7:00 AM | 7:32 AM | 8:17 AM | 4:22 PM | 5:06 PM | 5:38 PM | 9h 34m |
| December | 7:32 AM | 8:06 AM | 8:55 AM | 4:05 PM | 4:54 PM | 5:27 PM | 8h 48m |
Local time (America/Boise), including daylight saving time. Golden hour runs from about −4° to +6° solar altitude, so the morning golden hour begins during blue hour, before sunrise.
Milky Way & night sky
From Lemhi Pass, the Milky Way core is visible in a dark sky from April through August. June gives the longest window (about 3.2 hours on a moonless night), and the core peaks around 16° above the southern horizon. Our light-pollution model puts the sky at about Bortle 1 (excellent dark-sky site), which is excellent for astrophotography.
| Month | Core visible (15th) | Hours | Max altitude | Direction |
|---|---|---|---|---|
| January | Below 10° in darkness | — | -4° | — |
| February | Below 10° in darkness | — | 7° | — |
| March | 5:38 AM – 5:58 AM | 0.3 | 12° | SSE → SSE |
| April | 3:37 AM – 4:57 AM | 1.3 | 15° | SSE → S |
| May | 1:35 AM – 3:45 AM | 2.2 | 16° | SSE → S |
| June | 11:56 PM – 3:06 AM | 3.2 | 16° | SSE → SSW |
| July | 11:39 PM – 1:49 AM | 2.2 | 16° | S → SSW |
| August | 10:37 PM – 11:47 PM | 1.2 | 15° | SSW → SSW |
| September | 9:27 PM – 9:47 PM | 0.3 | 12° | SSW → SSW |
| October | Below 10° in darkness | — | 7° | — |
| November | Below 10° in darkness | — | -3° | — |
| December | Below 10° in darkness | — | -20° | — |
Window when the galactic core is at least 10° high during astronomical darkness on the 15th of each month. Pick nights within a few days of the new moon. Plan exact nights with the Milky Way planner.
Estimated sky darkness: 1 Bortle 1 — Excellent dark-sky site. The Milky Way casts faint shadows; zodiacal light and airglow are obvious. Modeled zenith brightness ≈ 21.94 mag/arcsec². Aurora needs roughly Kp 5.5+ to show low on the northern horizon here.
Weather & best season
Long-term NASA satellite data for this area show July as the clearest month (about 37% average cloud cover) and March as the cloudiest (67%). July is the warmest month and January the coldest, which matters for gear, snow access and how long batteries last at night.
Average cloud cover (%)
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| High °F | 38 | 46 | 61 | 70 | 81 | 87 | 93 | 91 | 87 | 77 | 62 | 44 |
| Low °F | -31 | -24 | -11 | -2 | 13 | 23 | 32 | 31 | 19 | -3 | -22 | -26 |
| Precip. (in) | 1.6 | 1.7 | 1.9 | 1.9 | 2.2 | 1.9 | 1.0 | 0.8 | 1.3 | 1.4 | 1.6 | 1.9 |
Monthly climatology for the surrounding 1° grid cell from NASA POWER (MERRA-2). Mountain sites can be colder and cloudier than the cell average.
Photography tips for this mountain pass
- Look for the road itself as a leading line — switchbacks from above make strong compositions.
- Weather changes fast at elevation; carry layers even in summer.
- Summit pull-outs often face one direction; use the sun azimuth table to see whether sunrise or sunset suits the view.
- Wildflowers bloom late at pass elevations — often July to early August in the Rockies and Sierra.
- Tell someone where you're going in remote areas and carry the ten essentials.
Season: Summer and early autumn are the main season; winter visits depend on plowing and avalanche conditions.
Suggested gear: Telephoto lens, Tripod, Warm layers, Road-condition app. Work out exposures with the depth of field, ND filter and NPF rule calculators.
Nearby photo spots
Other locations within 25 km of Lemhi Pass, closest first.
Campgrounds nearby (Recreation.gov)
- Agency Creek Campground9.3 km (5.8 mi)
- Horse Prairie Cabin11.0 km (6.9 mi) · reservable
- Bloody Dick Cabin15.8 km (9.8 mi) · reservable
- Mcfarland Campground21 km (13 mi) · reservable
- Mcfarland Campground21 km (13 mi)
FAQ
When is the best time to photograph Lemhi Pass?
What time is golden hour at Lemhi Pass?
Where does the sun rise and set at Lemhi Pass?
Can you see the Milky Way from Lemhi Pass?
Do you need a permit to photograph at Lemhi Pass?
How far is Lemhi Pass from Salmon?
Sources
Location data: Wikidata, Wikipedia. Sun, moon and Milky Way times are computed by LWPhoto Atlas for 2026. Climate: NASA POWER. Sky darkness is a population-based estimate (Walker's law), not a measurement. See data sources & licenses.