Few peaks match the awesome grandeur of Sierra Blanca. At just below 12,000 feet in elevation, Sierra Blanca looms intimidatingly large from the sandy deserts and rangelands that surround the compact range. From some vantage points there is nearly 8,000 feet of elevation differential bewteen the viewer and the summit. Its snow-capped summit is visible well into the summer, from the sizzling deserts below.
Sierra Blanca has many superlatives: it is the highest mountain in southern New Mexico and the highest 'southern' mountain in the mainland USA (i.e. any higher US peaks are north of Sierra Blanca's latitude, and the next higher peaks south are in Mexico). It also has the highest prominence in New Mexico at over 5,000 feet above its defining saddle. The views from the summit are simply awesome. Sierra Blanca is the highpoint of Otero county, and for peakbaggers, nearby Lookout Mountain is the highpoint of neighboring Lincoln county.
From Ruidoso, drive north on highway NM-37 a few miles and turn left onto NM-532, following the signs to the Ski Apache complex. Follow the road to near its terminus. You will likely arrive in the pre-dawn, and park along the highway near the trailhead of trail #15. This is at the last turn before entering the ski complex, which will be gated shut during the night. From Ruidoso to the trailhead it's about 15 miles.
Well... the actual summit of Sierra Blanca lies on the Mescalero Indian Reservation. Technically one needs a permit to hike on Indian lands. The town of Mescalero on US-70 about 15 miles south of Ruidoso might be a good place to inquire. Or, you can simply just hike the peak and take your chances. Judging by the quantity of names in the summit register, I suspect most people do the latter. Use your best judgement.
Snows should be gone by July, and return about late October. Thunderstorms are a daily likelihood for most of July and August. September and October are usually very dry. Get a pre-dawn start if you go up during the monsoon (July-Aug).
For snow climbs, I can't comment. The final ridge is steep with rocky obstacles so even a bit of snow or ice could make it challenging.
(Regarding Lookout Mountain: this lies right in the ski complex and is very nearby a ski lift. In winter, one could ski-step a few feet up the slopes to the seating area (you read correctly) on the summit)
There are campsites sprinkled throughout the region, including some on the road up.
Most of the trails are in the Lincoln National Forest. Try 505-257-4095.
Further useful information can be found at the county highpointers website:
Otero County, New Mexico