My girlfriend, Tabbatha, and I ascended the North Lykken -> Skyline -> San Jacinto Peak route yesterday, 18 Mar 2015, starting at 0430. Wildflowers were abundant, especially at low and middle altitudes. Snow coverage from the beginning of The Traverse to Grubb's Notch was 5%, and there was no need for special equipment. We had lunch at Grubb's Notch at 1230 and departed the Long Valley Ranger Station at 1300.
Past the High Trail junction at the stream, the snow coverage on the trail increased to 90% on the north-facing slope. Microspikes or similar would have been best, but since we had crampons with us, we determined it was more efficient to travel uphill without using them. After passing Wellman's Divide, the east-facing slope had much less snow coverage. Clouds, which were not present before, began to move in swiftly. We continued on since we were prepared for cold weather and precipitation. A few hundred meters past the final switchback below Miller Peak, thundersnow began. There were many lightning strikes near us, and we were already in a vulnerable position. We decided to turn around less than 100 m below San Jacinto Peak, rather than take the increased risk of being struck in the more exposed terrain above.
We found that surface conditions had changed dramatically in just a few minutes. Graupel, perhaps up to 20 cm deep in some places, had covered the trail immediately below us. We descended quickly. It was now 1600, and once we reached dense tree coverage, we decided to bypass Wellman's Divide and took a bearing eastward toward Tamarack Valley. We were thankful to be wearing gaiters. The lightning subsided by the time we reached Tamarack Valley, and we walked through lightly falling snow toward Long Valley. After some route-finding, we arrived at Long Valley at 1800.
Had I known a beer costs $8 at the tram station, I would have carried one up and cached it in the snow. <grin>
-Jesse
