Mount Riley Wilderness — a wilderness area in Doña Ana County, New Mexico — is a popular subject for landscape photographers. It is part of Organ Mountains–Desert Peaks National Monument. It sits roughly 41 km (25 mi) W of La Union.
Mount Riley Wilderness is an 8,382-acre (3,392 ha) wilderness area in the Organ Mountains-Desert Peaks National Monument managed by the U.S. Bureau of Land Management in the U.S. state of New Mexico. Established in 2019, this Wilderness located on the eastern end of the West Potrillo Mountains and bordering the nearby East Potrillo Mountains, contains three shield volcanoes that rise prominently from the Chihuahuan Desert floor. Cox Peak is the high point of the wilderness area and the Potrillo Mountain Complex at an elevation of 5,930 feet (1807 m), Mount Riley sits at 5,905 feet (1799 m).From the Wikipedia article “Mount Riley Wilderness”, licensed under CC BY-SA 4.0.
Sunrise & sunset directions
At Mount Riley Wilderness the sunrise point swings a long way through the year: about 62° (ENE) at the June solstice and 118° (ESE) in late December. Sunset moves from 299° (WNW) in June to 243° (WSW) in December, and the midday sun climbs to 82° in summer but only 35° in winter.
| Date | Sunrise | Azimuth | Sunset | Azimuth | Noon sun | Daylight |
|---|---|---|---|---|---|---|
| March equinox (Mar 20) | 7:13 AM | 90° E | 7:20 PM | 271° W | 58° | 12h 07m |
| June solstice (Jun 21) | 6:04 AM | 62° ENE | 8:18 PM | 299° WNW | 82° | 14h 14m |
| September equinox (Sep 22) | 6:57 AM | 89° E | 7:06 PM | 271° W | 58° | 12h 09m |
| December solstice (Dec 21) | 7:05 AM | 118° ESE | 5:09 PM | 243° WSW | 35° | 10h 04m |
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
Wilderness areas reward those who camp: being on location at sunrise and in the dark is the main advantage over day visitors.
| Month (15th) | Blue hour starts | Sunrise | Golden hour ends | Golden hour starts | Sunset | Blue hour ends | Daylight |
|---|---|---|---|---|---|---|---|
| January | 6:43 AM | 7:10 AM | 7:46 AM | 4:51 PM | 5:27 PM | 5:54 PM | 10h 17m |
| February | 6:26 AM | 6:51 AM | 7:25 AM | 5:22 PM | 5:55 PM | 6:20 PM | 11h 04m |
| March | 6:55 AM | 7:19 AM | 7:52 AM | 6:45 PM | 7:17 PM | 7:41 PM | 11h 57m |
| April | 6:15 AM | 6:40 AM | 7:13 AM | 7:05 PM | 7:38 PM | 8:03 PM | 12h 58m |
| May | 5:45 AM | 6:12 AM | 6:47 AM | 7:25 PM | 7:59 PM | 8:26 PM | 13h 47m |
| June | 5:35 AM | 6:03 AM | 6:39 AM | 7:41 PM | 8:16 PM | 8:45 PM | 14h 13m |
| July | 5:46 AM | 6:14 AM | 6:49 AM | 7:41 PM | 8:16 PM | 8:44 PM | 14h 02m |
| August | 6:08 AM | 6:34 AM | 7:07 AM | 7:20 PM | 7:54 PM | 8:19 PM | 13h 20m |
| September | 6:29 AM | 6:53 AM | 7:25 AM | 6:44 PM | 7:16 PM | 7:40 PM | 12h 23m |
| October | 6:48 AM | 7:12 AM | 7:45 AM | 6:04 PM | 6:37 PM | 7:02 PM | 11h 25m |
| November | 6:12 AM | 6:38 AM | 7:13 AM | 4:35 PM | 5:10 PM | 5:36 PM | 10h 32m |
| December | 6:35 AM | 7:02 AM | 7:39 AM | 4:30 PM | 5:07 PM | 5:34 PM | 10h 05m |
Local time (America/Denver), 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 Mount Riley Wilderness, the Milky Way core is visible in a dark sky from February through October. June gives the longest window (about 6.3 hours on a moonless night), and the core peaks around 29° above the southern horizon. Our light-pollution model puts the sky at about Bortle 3 (rural sky), good enough for detailed Milky Way images.
| Month | Core visible (15th) | Hours | Max altitude | Direction |
|---|---|---|---|---|
| January | Below 10° in darkness | — | 2° | — |
| February | 4:37 AM – 5:27 AM | 0.8 | 18° | SE → SE |
| March | 3:48 AM – 5:48 AM | 2.0 | 25° | SE → SSE |
| April | 1:43 AM – 5:13 AM | 3.5 | 29° | SE → S |
| May | 11:42 PM – 4:32 AM | 4.8 | 29° | SE → SSW |
| June | 9:56 PM – 4:16 AM | 6.3 | 29° | SE → SW |
| July | 9:53 PM – 2:53 AM | 5.0 | 29° | SSE → SW |
| August | 9:22 PM – 12:52 AM | 3.5 | 29° | S → SW |
| September | 8:38 PM – 10:48 PM | 2.2 | 26° | SSW → SW |
| October | 7:58 PM – 8:48 PM | 0.8 | 18° | SW → SW |
| November | Below 10° in darkness | — | 3° | — |
| December | Below 10° in darkness | — | -18° | — |
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: 3 Bortle 3 — Rural sky. Some light domes sit on the horizon, but the Milky Way still looks complex overhead. Modeled zenith brightness ≈ 21.62 mag/arcsec².
Weather & best season
Long-term NASA satellite data for this area show October as the clearest month (about 29% average cloud cover) and July as the cloudiest (52%). June 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 | 76 | 85 | 91 | 96 | 105 | 110 | 109 | 107 | 102 | 95 | 86 | 78 |
| Low °F | 19 | 8 | 20 | 32 | 40 | 56 | 62 | 59 | 47 | 28 | 20 | 19 |
| Precip. (in) | 0.5 | 0.5 | 0.2 | 0.2 | 0.2 | 0.4 | 2.5 | 1.8 | 1.6 | 0.7 | 0.5 | 0.6 |
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 wilderness area
- Night skies are often among the darkest in the country.
- Motorized and mechanized equipment, including drones, is prohibited in designated wilderness.
- Group size limits and permits may apply; check with the managing agency.
- Practice Leave No Trace — camp on durable surfaces away from lakes and streams.
- Pack weight matters: a single zoom and a light tripod cover most situations.
- Shoot RAW to keep the most latitude for high-contrast sunrise and sunset scenes.
Season: Most high wilderness is snow-free from July to September; lower deserts are best in spring and autumn.
Suggested gear: Lightweight tripod, Spare batteries, Headlamp, Navigation. Work out exposures with the depth of field, ND filter and NPF rule calculators.
Permits, drones & access
Drones: Drones may not take off from or land in federally designated wilderness, where mechanized equipment is prohibited under the Wilderness Act.
Nearby photo spots
Other locations within 40 km of Mount Riley Wilderness, closest first.
Wilderness Area
Wilderness Area
State ParkFAQ
When is the best time to photograph Mount Riley Wilderness?
What time is golden hour at Mount Riley Wilderness?
Where does the sun rise and set at Mount Riley Wilderness?
Can you see the Milky Way from Mount Riley Wilderness?
Do you need a permit to photograph at Mount Riley Wilderness?
How far is Mount Riley Wilderness from La Union?
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.