I started today hiking from San Jacinto Peak to the PCT via Little Round Valley, then surveyed almost all the PCT above 8000′ (Fuller Ridge southbound to Saddle Junction), and finished with Devils Slide Trail. At San Jacinto Peak it started snowing at 0630, and continued lightly until 0930.
Overview Last night most trails and many exposed aspects were snow-free. However, the entire mountain above about 5500′ received a light dusting of snow today. It is fair to assume that almost all major trails on the mountain currently have a light covering of snow. I measured about 1.0″ (2.5cm) at San Jacinto Peak and Annie’s Junction, 0.75″ in Little Round Valley, and 0.5″ at Strawberry Junction and Saddle Junction. The snowfall was largely graupel, a powdery hail-like snow that actually makes traction very easy on trails when it is fresh. Although traction aids (e.g., microspikes) are not currently essential, this may change as the current snow goes through freeze-thaw cycles and starts to become icy, especially where it is compacted by hiker traffic. Conditions may also change further as it is snowing again lightly this evening (at least in Idyllwild at 5550′), and further snow is forecast for the whole mountain later this week.
Severe cold This is the biggest hazard at present. Early this morning at San Jacinto Peak I recorded a temperature (including windchill effect) of -24.7° F (-31.5° C)! (See video below.) While this is extreme, temperatures are forecast to remain well below freezing at night above 6000′ (1800m), and at higher elevations below freezing all day, for at least the next 10 days. These forecast temperatures do not include additional dangerous windchill effects. Unless you are certain that you have the very best equipment suitable for such conditions, camping above 8000′ (2400m) for at least the next 10 days could be life-threatening.
Water The only concern with water right now is that most sources above 8500′ are frozen solid. This will remain a problem, especially in the mornings, for at least the next several days. For example at the crossing of the North Fork of the San Jacinto River on Fuller Ridge today at noon, I was unable to kick through several inches of solid ice with a hiking boot heel to reach the flowing trickle underneath (see photo below).
Pacific Crest Trail While much of the PCT through the San Jacinto Mountains is currently covered with a little snow (<1″), the route is relatively easy to follow. By this afternoon, the snow from the morning was already starting to melt on some sections on exposed southerly aspects (e.g., near Strawberry Cienega). Hikers very unfamiliar with snow/ice travel will find microspikes useful in some areas. Please also see comments above regarding severe cold, water problems, and additional forecast snow.
Upper Deer Springs Trail (from Fuller Ridge Junction to San Jacinto Peak) Lightly snow-covered (generally <1″ but 2-3″ in areas of drifting). In Little Round Valley about 90% snow cover of a few inches from January storms persists (under the fresh snowfall), but the trail is still fairly clear.
Devils Slide Trail Largely clear below 7000′, a very light covering of snow above 7000′.