Elain and I had been wanting to climb the North Ridge of Pinnacle Peak for some time. Although avalanche hazard had thwarted a previous attempt this winter, we had gained knowledge of the approach and a digital photo of the northwest face of the north ridge. From our scouting trip we learned that the lower part of the route is actually not on the north ridge, but on the northwest face of the ridge. The avalanche and weather forecasts for Saturday looked favorable, but Sunday's forecasts looked grim, with a low-pressure system expected to come through the Cascades Saturday night. Officially, the Park Service doesn't open the gate at Longmire until 10:00 AM and closes it at 6:00 PM, which is too short a window for us to realistically make a car-to-car ascent. However, we heard a rumor that the Park Service sometimes opens the gate as early as 8:00 AM, when the weather is good. After some discussion, we decided that a car-to-car ascent might be possible with an 8:30 start. It was worth a try, anyhow.
When we arrived at Longmire at 7:30, there was already a queue of cars waiting to drive up to Paradise. We asked around about the gate, and found out that the park rangers were planning to open the gate a 8:00. We were delighted when the gate opened just after 8. By 8:30 AM, we were hiking up the snow slope above Narada Falls. The approach to Pinnacle Peak was pretty straightforward, with just a bit of sidehilling on steep snow slopes. By 10:30 AM we reached treeline at 5660', just below the northwest face of the north ridge. There we left our snowshoes and trekking poles, hoping it would be easy to pick them up on the way back down. [At this point we were not sure whether we would descend via the ascent route or via the Pinnacle-Plummer col or via the Pinnacle-Castle col.] Another hundred feet higher we reached the base of the route, at which point we broke out the rope and rack. The sun was starting to boil off the morning fog, and it was warming up considerably. The slope we were climbing was still in the shade, and snow conditions were excellent for cramponing. We simul-climbed up the face, using the occasional picket or tree-sling for protection. A 15' step of quite steep snow and a short mixed gully were the only speedbumps in an otherwise mellow (average 45 degrees) 5 pitches of simul-climbing, at the end of which we reached the high side of a prominant notch in the spine of the north ridge. This was the start of the belayed climbing.
The first obstacle above the notch was a large gendarme. It was immediately obvious that we could not climb straight up the gendarme. Fortunately, we spied a narrow down-sloping ledge that skirted up and left around the base of the gendarme. For the first belayed pitch, we traversed along this ledge, and then around a corner into a steep, exposed gully. The gully was about 65 degrees containing aerated snow-ice that was poorly bonded to the underlying rock. At the base of the gully, a sheer cliff dropped away several hundred feet to the Pinnacle Glacier. I gingerly kick-stepped my way up the gully, shafting my tools with each step. Near the top of the gully the slope steepened and the snow became rather thin, and I was relieved when I topped out onto the spine of the ridge. I protected the gully with pickets, but it is unlikely they would have held. Elain joined me at the belay spot, which was perched on a knife edge with spectacular drops on either side. Our relief turned to worried concern when we studied the second pitch. A 40' rock wall barred further progress along the ridge. Not being rock climbers, this was an unwelcome development. To improve the odds, I switched to bare hands, but (expecting more mixed climbing above the step) kept the crampons on and the tools handy. The first few moves were on an arete on the left hand side of the step. At this point, the arete gave way to a corner and the angle steepened. At the top of the rock step the angle of the ridge spine moderated a bit, but became devoid of holds. This forced me to traverse leftward out onto the steep, snow-plastered east face. Out came the gloves and tools. I climbed up the east face where the ice met the rock, torquing my pick in small cracks in the rock and with one crampon on ice and the other on rock features. In this fashion I eventually reached the spine of the ridge, at which point I welcomed some moderate ridge scrambling until I reached a suitable belay spot.
When Elain joined me, we studied the third pitch. The start was a 10' rock step, leading up onto a small rib. From there, the route presented two options. Along the ridge spine, two small spires blocked progress, but could perhaps be climbed directly. Alternatively, we could traverse out across the east face and attempt to reach a north-facing snow ramp that appeared to lead directly to the lee side of the summit cornice. Neither option was particularly appealing. In the end I compromised, climbing partway up the first rock spire, then bailling and doing a high traverse across rock, snow and moss to meet the upper part of the snow ramp. The snow ramp was steep and sugary, but provided just enough support to make progress. Most of the summit cornice was overhanging, but mercifully where the snow ramp terminated the cornice lip was merely vertical. With some inelegant moves and a fair bit of cursing, I was up onto the summit cornice. Another 20' of scrambling led to the true summit. The time was 3:15. Elain soon joined me, and we took a quick break to hydrate and put away some gear. We discussed our descent options, and agreed that we were not enthusiastic about descending the north ridge. Too many rappels, we would likely end up benighted. So we decided to descend the south face, and hoped that post-holing back over the Pinnacle-Plummer col without snowshoes would not be too awful.
By 4:00 we were scrambling back down the south face route. A quick rappel down a gully got us onto the snow slopes of the south face. We post-holed down the snow slope, slowly due to the sun-softened snow, eventually traversing over to reach the col. On the other side of the col, the north-facing slopes were much firmer and made for excellent cramponing. We were enthusiastically cramponing down into the huge basin below Pinnacle's northwest face when Elain realized we needed to start traversing over toward the north ridge to get our snowshoes. We soon realized that leaving our snowshoes so high up (5660') was a mistake; we had to side-hill on steep soft snow for what seemed like forever, crossing several steep ribs and gullies, before finally regaining the snow tracks from our ascent. We hiked up the gully for 100' to reach our snowshoes. After a short break, we started the hike out. Elain's routefinding skills allowed us to get back to the Stevens Canyon Road without any of the sidehilling on steep slopes that we had encountered on the ascent. The last of the twilight faded when we reached the road. Venus twinkled brightly through a break in the clouds. We quickly plunge-stepped down the snow slopes above Narada Falls, reaching the car at 7:34 PM. We drove down to Longmire and found (as expected) that the gate was closed and locked. Although we had overnight gear in the Jeep, we preferred to try and get home that night. We walked over to the National Park Inn and inquired with the innkeeper. She joked around a bit with us, but finally gave us the combination to the gate lock.
We later found out that the Park Service had actually closed the gate much later than we had expected, at 7:30 PM.
Gear we used: ice tools, crampons, 50m x 8.5mm double ropes; #3 knifeblade; 2 bugaboos; Ushba wedge piton; #3 nut; #8 hex; #3 friend; various tri-cams from #0.5 through #2.5; screamers; pickets
Things we learned:

Photograph of the west face of Pinnacle
Peak (taken a few weeks prior to our ascent). Our approximate route
is shown in red. The dotted line means that our route was on
the other side of the ridge (out of view).

Photograph of the east face of of Pinnacle
Peak (taken a few weeks prior to our ascent). Our approximate route
is shown in red.

Steve in front of the big gendarme on the north ridge

Steve approaching the snow traverse on the first pitch

Steve just below the third pitch. The overhanging summit
cornice can be seen in the top of the picture. It is actually
about 40m from where I am standing, but looks closer due to forshortening.

Steve starting the third pitch