Category Archives: weather

San Gorgonio Mountain Snow, Avalanches and Glaciers

Snow on the Sky High Trail on San Gorgonio Mountain on July 27, 2019.
Snow on the Sky High Trail on San Gorgonio on July 27. San Jacinto Peak is in the distance.

Update July 21, 2023. Another big snow year. This Google Earth image of San Gorgonio Mountain is overlain with Copernicus/ESA Sentinel 2 imagery taken on July 19, 2023. The GPS track (yellow) is the upper portion of the Dollar Lake – Dry Lake Loop, a keyhole loop that starts at the South Fork Trailhead.

The weather was Southern California perfect. Shorts and short-sleeves were the dress of the day. Winds were light, no thunderstorms were in the forecast and no large wildfires polluted the air. Although temps in the valleys were nearing 100 degrees, the weather on the summit of 11,499′ San Gorgonio Mountain was altitude-conditioned bliss.

I’d spent about 15 minutes enjoying the summit, then run back down the Summit Trail. Turning left onto the Sky High Trail, I continued a keyhole loop that had ascended the South Fork Trail, Dollar Lake, and San Bernardino Divide Trails. Altogether, the route was about 21 miles long and the approximate elevation gain/loss was 4700′.

San Gabriel beardtongue (Penstemon labrosus) along the South Fork Trail.
Penstemon along the South Fork Trail.

From the start of the run, the effects of the wet 2018-19 Winter and big snowpack were everywhere. Wildflowers bloomed in profusion, seeps and small streams greened the landscape, and grasses and ferns grew thick beneath the trees. The roar of the streams at South Fork Meadows left little doubt as to what kind of Winter it had been.

On the way up the Dollar Lake Trail, I’d seen elongated patches of snow in the chutes along the crest. While there was no snow directly on the trail between Dollar Lake Saddle and the summit, there was more snow than usual on the north side of the peaks.

But there was snow on the Sky High Trail. Topping out at over 11,300′, the Sky High Trail is one of the most spectacular trails in Southern California. I marvel at its airy location every time I run it. Near the top of the trail, I’d crossed a small patch of snow and thought, “Well, at least there was a little snow on the trail.”

Large patch of snow on the Sky High Trail at an elevation of about 11,100' on July 27, 2019.
Large patch of snow on the Sky High Trail at an elevation of about 11,100′ on July 27, 2019.

A little disappointed, I’d put my poles away and continued running down the trail. At around 11,100′ I rounded a corner and surprise, surprise — there was a much larger patch of snow on a southeast-facing section of trail. It was about 100 yards across and steep enough that a fall would be a bad idea. Fortunately, the snow conditions were perfect. A few hikers had recently traversed the snowfield, and I followed in their footsteps.

However, that wasn’t the last of the snow. At an elevation of about 10,200′, not far past the C-47 crash site, the trail crosses a long chute that extends nearly to the top of Gorgonio. The snow in that chute had melted just enough that a thin strip of trail was exposed.

Thinking that had to be the last of the snow, I continued the traverse to Mineshaft Saddle (9936′) and began the descent of the Dry Lake Trail. Once past a rocky section of the trail, I picked up the pace, energized by the increased oxygen at lower elevation. Enjoying the downhill, I descended into an area of converging chutes and gullies, when the path through the lodgepole forest abruptly ended.

Avalanche debris on the Dry Lake Trail above Dry Lake. July 27, 2019.
Avalanche debris on the Dry Lake Trail above Dry Lake.

The trail was obliterated. Large trees were ripped from the ground, broken, tossed, and piled up as if they were matchsticks. Underneath the debris were mounds of dense, icy snow — the remnants of an avalanche. This report on SoCalSnow.org includes photos of an avalanche in February 2019 on the north face of San Gorgonio and mentions previous avalanches.

That snow, at an elevation of about 9400′, had finally been the last on the trail. Because the compressed snow is effectively a big block of ice, it could be around for a while.

In the area of the avalanche, the Dry lake Trail enters a large area of rocky rubble that extends into the Big Draw. According to the Dibblee Geologic Map for San Gorgonio Mountain, this rubble is glacial till, produced by the largest of several pocket glaciers that existed on San Gorgonio Mountain, Shields Peak, and San Bernardino Peak.

San Gorgonio Mountain's summit, on the left of the crest, is more than 2400' above Dry Lake.
This is the first time Dry Lake has been full this time of year since 2011.

Continuing down the trail to Dry Lake I saw where some of this season’s meltwater had gone — for the first time since 2011, Dry Lake was full in late July.

Last Saturday’s run was so enjoyable that yesterday I went back to Gorgonio and did it again. As might be expected during a Southern California Summer heatwave, the snow on the Sky High Trail, and elsewhere, is melting fast and won’t be around for long.

Here are a few photos taken along the way. The album includes photos from both the July 27 and August 3 runs. A couple of photos from a run on September 7 were also added.

Some related posts: San Gorgonio Mountain Snow Follow Up, Still a Little Snow in Southern California; San Gorgonio Mountain: Falls Creek Loop, August 2017; After the Lake Fire: The Dollar Lake – Dry Lake Loop on San Gorgonio Mountain

Upper Las Virgenes Creek Still Flowing in Mid-July

Upper Las Virgenes Creek, July 17, 2019.

Following our five year drought, Downtown Los Angeles and many neighboring areas recorded above-average rainfall in two of the last three rain years. This has had obvious and observable effects on the area’s plants and animals and aided in the ongoing recovery of habitats affected by drought and wildfire.

This is the first time since the Summer of 2011 that there has been flowing water in upper Las Virgenes Creek in mid-July at the crossing near the Cheeseboro connector. It’s just a trickle, but keep in mind that during some of the drought years, this section of upper Las Virgenes Creek never flowed.

Update November 19, 2019. Increased surface water and pooling in Upper Las Virgenes Creek. See the post Running Into Fall.

Update August 28, 2019.  The surface flow of Upper Las Virgenes Creek near the Cheeseboro connector is down to a bare trickle and some small pools.

Update August 7, 2019. Upper Las Virgenes Creek is still trickling.

Notes: In rain year 2016-17 Downtown Los Angeles (USC) recorded 19.00 inches of rain from July 1 to June 30, and in 2018-19, 18.82 inches. During the intervening rain year, 2017-18, only 4.79 inches was recorded.

Warming Up for the ANFTR Trail Races

Stratus in the San Gabriel River drainage from Mt. Wilson road.

Was back on Mt. Wilson this morning, enjoying the mountains, and getting in a little more training for the upcoming Angeles National Forest Trail Run races.

There were already two cars parked in the loop road turnout when I got there, and another car pulled in behind me. All were runners.

The turnout is near the start of the ANFTR course and most of the runners were planning to do the ANFTR 25K loop or a variation. One runner — training for the ANFTR 60K and AC100 — was doing the 50K course.

The extensive layer of low clouds in the canyons of the West Fork and East Fork San Gabriel River at the start of the run was indicative of a cool onshore flow. Too cool and comfortable, really. Anticipating warmer temperatures for the ANFTR race, I wore an extra layer for the run, and probably should have worn more.

The last two years the ANFTR races have been run during record-setting heatwaves. We’ve had a lot of cool weather this year and for a while it looked like the pleasant weather might carry over to race day, July 6. But following the finest of ANFTR/Mt. Disappointment traditions, it now looks like temps will probably be warming up for the race. Maybe not quite as hot as the last two years, but still on the toasty side. We’ll see!

The highest temperature recorded at Clear Creek on the day of the ANFTR/Mt. Disappointment races for 2005-2019.
High at Clear Creek for the 2005-2019 ANFTR/Mt. Disappointment races. Click to enlarge.
Average hourly Clear Creek temperatures on the day of the ANFTR/Mt. Disappointment races for 2005-2019.
Hourly Clear Creek temperatures for 2005-2019 ANFTR/Mt. Disappointment races. Click to enlarge.

Update Thursday, July 11, 2019. As it turned out, temperatures for the 2019 edition of the Angeles National Forest Trail Run were in the “middle of the pack” compared to other years. The high temperature recorded at the Clear Creek RAWS on July 6 was 80°F. This was down 25°F from 2018. Hourly fuel temperatures at Clear Creek ranged from 101°F to 104°F between noon and 5:00 pm. The high at the Mt. Wilson RAWS on July 6 was 75°F, down 20°F from 2018.

Average hourly Clear Creek fuel temperatures on the day of the ANFTR/Mt. Disappointment races for 2005-2019.
Hourly Clear Creek fuel temperatures for the 2005-2019 ANFTR/Mt. Disappointment races. Click to enlarge.

Note: The temperature in a commercial weather station is measured inside a white, ventilated instrument housing, several feet off the ground. Mid-day temperatures in the sun, in the summer, with a cloudless sky will be much warmer than this. Some stations, such as Clear Creek, also measure the fuel temperature — the temperature of a pine dowel in direct sun about a foot off the ground. According to the NWS (and common sense) exposure to full sunshine can increase heat index values by up to 15°F. In my experience the fuel temp gives a better indication of the actual temperature a runner can experience in the sun, especially on exposed mountain slopes facing the sun.

Update Monday, July 1, 2019. Last week the GFS weather model was forecasting temps on race day to be near 100 at the lower elevations and over 90 on Mt. Wilson. This morning’s GFS max temperature forecasts are down about 10 degrees from that. Basically highs in the low 90s (in the shade) for the lower elevations and around 80 at Mt. Wilson. Temps in the sun, especially on exposed sun-facing slopes, could still top 100. If the forecast holds, the temperatures today should be similar to those on race day. We’ll see! Here are links to the Clear Creek RAWS and Mt. Wilson RAWS.

Some related posts: ANFTR/Mt. Disappointment 2019, Another Scorching Angeles National Forest/Mt. Disappointment Trail Race, Record Heat for the 2017 Mt. Disappointment 50K & 25K

Lasky Mesa: Dark Clouds and Sun

Dark Clouds and Sun. Photography by Gary Valle'.

From a run this May in Upper Las Virgenes Canyon Open Space Preserve (Ahmanson Ranch).

Normal rainfall for May at Downtown Los Angeles (USC) is 0.26 inch. This year Los Angeles recorded 0.81 inch in May, according to the NWS .

It was definitely wet and cool! Nineteen days were partly cloudy to cloudy. Ten days recorded at least a trace of rain. The average high was 70 degrees.

Oddly, during our recent drought, above normal May rainfall totals were recorded in 2011 (0.45 inch), 2013 (0.71 inch), and 2015 (0.93 inch). The most rainfall recorded in May at Los Angeles was 3.57 inches in 1921.

Islip Saddle to Baden-Powell: No Worries About Snow Flurries

Mine Gulch and Mt. Baldy from Mt. Baden-Powell on June 8, 2019.
Mine Gulch and Mt. Baldy from Mt. Baden-Powell

Each year, around Memorial Day, I like to do the out and back on the Pacific Crest Trail from Islip Saddle to Mt. Baden-Powell. It’s fun to see how much snow (if any) remains on Mt. Baden-Powell and to get an idea of how much snow there is on Mt. Baldy, San Jacinto Peak and San Gorgonio Mountain. It’s also a good way to continue acclimating to higher elevation.

Snow at 8750' near the junction of the PCT and Dawson Saddle Trail in the San Gabriel Mountains, near Los Angeles.
Snow at 8750′ near the junction of the PCT and Dawson Saddle Trail

This year I was a couple of weeks late getting to Baden-Powell, having done runs on Mt. Wilson Memorial Day weekend and Mt. Waterman the weekend after. That’s OK, over much of the holiday weekend it was cold and snowy at the higher elevations of the local mountains. The temperature at the Big Pine RAWS (6964′) was in the thirties all day Sunday, May 26, and it was certainly much colder than that at 9400′ on Baden-Powell.

There were no worries about snow flurries and cold weather today! The weather was perfect for the run. Cool in the shade and warm in the sun.

Summit of Throop Peak in the San Gabriel Mountains, near Los Angeles.
Summit of Throop Peak.

In some places between Throop Peak and Baden-Powell, there was still snow on the trail, but it could be avoided by moving to the sunny side of the crest. The last time there was more snow here in late May – early June was in 2010.

Perhaps because of the more seasonable weather, there were many (mostly) happy people on the trail that, like me, were thoroughly enjoying the wonderful day.

Related post: A Cool and Breezy Out and Back Trail Run from Islip Saddle to Mt. Baden-Powell

Painted Lady Butterflies in Upper Las Virgenes Canyon Open Space Preserve

Painted Lady Butterflies in Upper Las Virgenes Canyon Open Space Preserve. May 12, 2019.
Painted Lady Butterflies

Back in March, a profusion of painted lady butterflies in Southern California made headlines. The colorful insects were said to be passing through the area on their way to Oregon and other points to the north.

Two months later millions of the black, orange and white butterflies continue to be seen in the West San Fernando Valley, Upper Las Virgenes Canyon Open Space Preserve (Ahmanson Ranch), and other areas. Recently there has been an uptick in their numbers and there have been some remarkable displays of the flyers along local trails.

Painted lady in Upper Las Virgenes Canyon Open Space Preserve with the characteristic four eyespots on the hindwing.
Painted lady in Upper Las Virgenes Canyon Open Space Preserve with the characteristic four eyespots on the hindwing. Click for a larger image.

There are three very similar species of “lady” butterflies in the genus Vanessa — the painted lady (Vanessa cardui), the American lady (Vanessa virginiensis) and the west coast lady (Vanessa annabella). The Canadian Biodiversity Information Facility web site has a side-by-side comparison of these species and this post on BugGuide.net compares the American lady to the painted lady.

The lady butterflies I’ve looked at closely in Upper Las Virgenes Canyon Open Space Preserve have the identifying characteristics of the painted lady (Vanessa cardui). Here are an open-wing photo and a closed-wing photo of painted lady butterflies in Upper Las Virgenes Canyon Open Space Preserve.

This three-minute slow-motion video of painted lady butterflies in upper Las Virgenes Canyon reveals their fluid, bird-like flight. The purple flowers in the video are winter vetch, an introduced plant which is also more abundant this year.