Great Thanksgiving snow storm 27th-29th November 2019

The past three days has seen the most prodigious November snow storm to occur in the San Jacinto mountains in living memory. The quantities of snow that have fallen would not be unexpected in say January or February, but in November?!

The depths that accumulated at mid and lower elevations were especially remarkable, including a November record for Idyllwild, where meteorological records began in 1943. The previous record for Idyllwild snowfall in November was 19.5″ in 1952 (and even that may not have been all in one storm event).

Videos from San Jacinto Peak on each of the last three days are on YouTube, the latest being from just after sunrise Saturday morning.

Special thanks to the indefatigable Anne for reporting on weather conditions in Idyllwild while I was on the mountain for an extended period, and to Kyle Eubanks for company on Wednesday/Thursday and for always reliable snow depth data on the route to/from the Tram.

Currently the USFS gate at Humber Park remains open. Regardless, there are always up to nine legal parking spaces this side of the gate (near the upper Ernie Maxwell trailhead). The next closest legal parking is just downhill on Forest Drive.

Currently many major trails have not been traveled and are obscured by heavy snowfall. Cautious navigation is strongly recommended everywhere.

Snow depths measured today are listed at the foot of this posting. Melting of the first snowstorm of the season last week had been considerable in most areas, with nearly half of last week’s snowfall lost above 8000′, and much more lost below that elevation.

Snow depths are currently ideal for snowshoeing almost everywhere above about 5000′ elevation. This will change with rapid melting already underway below 6000′.

Microspikes will become increasingly useful at lower and mid-elevations over the next few days as established trails become consolidated by hiker traffic and undergo freeze-thaw cycles. They are especially useful for descending trails when they become icy and compacted.

Crampons (always with an ice axe if you know how to use it) may become useful around the high peaks once the snow has consolidated over the next few days.

Hikers should be prepared for temperatures at or below freezing in the high country, and well below freezing when considering windchill effects.

Looking south-east from San Jacinto Peak early this morning, 30th November 2019, with the rising sun reflecting off the Salton Sea.

WEATHER As is seemingly normal these days a rapid warming will result in temperatures at or even above freezing as high as San Jacinto Peak by 1st December. Another (small this time!) snow storm, with rain below about 7000′, arrives on 3rd/4th December, before yet further warming.

At San Jacinto Peak (10,810ft/3295m) today, Saturday 30th November 2019 at 0640 the air temperature was 20.6°F (-7°C), with a windchill temperature of -2.5°F (-19°C), 23% relative humidity, and a sharp WNW wind sustained at 17 mph gusting to 28.3 mph.

At the Peak on Friday 29th November 2019 at 0840 the air temperature was 6.2°F (-15°C), with a windchill temperature of -18.2°F (-28°C), 100% relative humidity, and a brisk WNW wind sustained at 11 mph gusting to 23.2 mph, while snowing heavily.

Jean Peak (left side of the image) as seen from San Jacinto Peak before sunrise, 30th November 2019.

TRAIL CONDITIONS

All trails above about 4500′ are covered with between 10″ and 35″ of snow, depending on elevation. This includes the Pacific Crest Trail from south of Mile 151 (the Hwy 74 crossing) to about Mile 196.

Reliable, well-traveled tracks are currently in place only for Devil’s Slide Trail, from Saddle Junction to San Jacinto Peak, and from the Tram through to Wellman Divide. However strong winds in the high country will have obscured tracks within hours or even minutes.

SNOW DEPTHS measured today are as follows. Average depth is given. With strong winds during this storm, drifts are significantly deeper than the average in places. Altitudes are approximate.

San Jacinto Peak (10810′): 36″ (incl. 4″ on morning of 27th November) (drifts to 50″ on east side).

Wellman Divide (9700′): 17″

Annie’s Junction (9070′): 24″

Saddle Junction (8070′): 25″ (includes 4″ on 25th November)

Devil’s Slide Trail at Humber Park (6550′): 17″

Idyllwild (at 5550′): 21″ (storm total, but already melting rapidly today)

PCT Mile 151 (at its crossing with Highway 74) (4700′): 12″ (thanks to Jill G. for this information)

Summit hut (10,700′) at San Jacinto Peak on Saturday 30th November 2019 (above), and the same view on Wednesday 27th November 2019 (below).

Wellman Divide (9700′) this morning 30th November 2019 (above), and the same view on Wednesday 27th November 2019 (below).

Jon recording the weather at San Jacinto Peak on Thanksgiving Day 2019 in -7°F (-22°C) windchill conditions (photo courtesy of Kyle Eubanks).