This route that is written here is only recommended for winter use. The route is doable in summer. However it involves a lot of extra effort such as intense bushwhacking, scrambling and off trail navigation. Also the footing in this section of mountains often can be poor with mossy rocks and lots of thick underbrush and steep slopes.
In winter many of these obstacle are ruled out by three or more feet of firm snow. The route cutting over the low point on Skyline Ridge becomes dramatically more doable with the firmer snow covering over the thick underbrush, mossy rocks, scrambling and the scree navigating that is needed in the summer. This now becomes an enjoyable winter climb that is very easy to access on most winter days and the trailhead is very obvious. I highly recommend this summit and maybe linking Sky Mountain to your winter plans. Adding Skyline Ridge would a little more dicey, especially if you are trying to reach the true summit. Skyline Ridge is a true scramble and the rocks covered with snow could be very interesting in icy conditions. I would advise saving Skyline Ridge for a short summer scramble.
VIA STEVENS PASS: Take Route to Stevens Pass when at the ski area park in the overflow lot on the north side of the highway from there you will see a snow filled road. That will be where you start for your trip to the summit. It should be noted that in winter there is no charge to park there.
From the Parking area you want to head north to the snowy road that is left of a gray building. Take this road, which will be a packed down ski and sledding trail up the mountain. This particular section usually is heavily traveled. In summer this is a dirt road and there actually is a climbers path. But in winter this climbers path is not available much of the time so it is easier just to stick to the dirt road as it rises up the mountain.
Once up roughly a mile and nearly 1000 feet of elevation gain you will hit a Y intersection with two path. The right will continue to cell tower which you don't want and the left one will take you to Lake Skyline. Take the left path.
Once you hit Lake Skyline traverse around the lake in order to hit Skyline Ridge and aim for a gap in the ridge northwest of Lake Skyline and east of Skyline Ridge. Once in the gap look for the safest way to decend from the gap. All ways will be steep but there are some good ways through the trees that are fairly safe from avalanche danger. Head down roughly 150 feet (the slope I was on was roughly 50 degrees) and then once you are on more level ground traverse to the left. You will see Tye Peak in front of you and should take note of the gap between Tye Peak and Sky Mountain. You want to head over to that gap while trying your best to maintain the elevation you have. In summer this terrain is very rocky and brushy but in winter many of these obstacle are snowcovered making for easy travel.
Once in the gap make a right and head straight up the ridge to the summit of Tye Peak. An ice axe will required for most winter trip up this mountain. You should take note of cornices and avalanche conditions before you continue to the summit. Stay on the high slopes as much as possible when you are on this ridge. Soon you will hit the summit and be able to enjoy if you are lucky great views of the Central Cascades. Return the way you came.
In order to be successful in the route an ice axe, and snowshoes are absolutely required. Keep in mind that you will be the only person heading for the mountain on that day so bring enough food and water just in case you run into serious issue. Though it is close to Stevens Pass once you go over that ridge you are in true backcountry wilderness. Therefore it is always advised that a shovel is brought as well as a light weight bivy. As with all winter hikes and climbs proper clothing as well as the 10 essential are required.
External Links For the best weather and snow conditions in the immediate surrounding reach go www.stevenspass.com or click here
Here is a link to shots of live shots of Stevens Pass.
Here is the Noaa forecast for the western Cascades