[UPDATE 3 May 2018 – I hiked San Jacinto Peak from Humber Park this morning. There were small patches of snow around 9000′ near the State Park boundary, from Wellman Divide to 10,100′, and above 10,500′. The snow was just 1-2″ deep and easily hiked without microspikes, and was melting fast already by mid morning. All other sections of trail were more exposed to direct sun and were completely clear. With a strong warming trend, almost all remaining fresh snowfall will likely have gone by Saturday 5th May.]
Today I surveyed the PCT along the Fuller Ridge Trail, then turned up to San Jacinto Peak via Little Round Valley, before returning by the same route.
Overview Today was an especially striking example of how quickly weather can change in the mountains. As expected a storm system overnight brought a dusting of snow above 5000′, a consistent 1.0″ (25mm) of snow on all trails above 6000′, and 1.5-2.0″ of snow on San Jacinto Peak above 10,500′. There was some drifting in the trails (to 4″ deep) in the most exposed areas, such as at the Peak >10,500′ and on the west slope of Fuller Ridge.
At San Jacinto Peak at 1200 today, I recorded a temperature of 23.5°F (-5°C), but the windchill under a light north-east breeze was down to 9°F (-13°C). At times during my hike it tried to snow again, and at others the sun put in brief appearances through the thick cloud.
In contrast to the sharp cold this morning, a very strong warming trend took hold in the afternoon, and even under cloudy skies there was dramatic melting everywhere. Trails that were completely snow covered in the morning were largely clear by the afternoon (see photos below). Remarkably by 1600, all areas below 8000′ were almost completely clear of snow.
Consequently the fresh snow had no significant impact on routefinding or the accessibility of any trails. No traction devices (e.g., microspikes) are necessary anywhere on the trail system.
Weather prognosis The strong warming trend that started this afternoon will continue and strengthen further for the next several days. By Friday (4th May) there will probably be no sign that we even had snow today!