I was running in the hills along the western margin of the San Fernando Valley and reveling in the Autumn-like weather. The hills were parched, brown, and the soil dessicated. In 128 days it had not rained.
An area of low pressure was producing some clouds and even a little rain in some parts of Los Angeles County. The last time it had been this cool in the afternoon was in mid-June. The pleasant temperature was a welcome change from the 80s, 90s and 100s of Summer.
Precipitation from the 2015-16 Godzilla El Nino fell short of expectations, with Downtown Los Angeles only recording 65% of normal rainfall and the drought continuing into its fifth year. How long would we have to wait until we received widespread rainfall?
At the moment the expectation is for ENSO Neutral conditions to prevail this Winter. Neutral conditions give forecasters little leverage on which to base their Winter outlook, but based on last year’s Southern California precipitation forecasts, we didn’t have much leverage then either.
With a warming planet, we appear to be in a new regime. Forecasts based on 1950-2000 analogs may no longer be applicable. As of September 15 the Climate Prediction Center’s Precipitation Outlook for Southern California for December, January and February is the equivalent of flipping a three-sided coin.
We may just have to wait and see what the Winter brings.
I squeezed the bag of ice wrapped in the bandanna around my neck and shivered as an ice cold bead of water snaked down my spine. The temperature reading from the shaded sensor clipped to my pack read 106°F.
That had been at 3:30 Thursday afternoon at Ahmanson Ranch. Earlier that day the “in the sun” temp recorded at the nearby Cheeseboro RAWS had topped out at a blistering 119°F!
This morning, Sunday morning, my AC100 heat training was on hold. The sun had just risen and I was running on the dew-covered sidewalk of the Golden Gate Bridge. The temperature sensor was reading about 54 degrees cooler than at Ahmanson — an almost chilly 52°F.
Not to worry — I would be back running in the 100 degree Ahmanson heat Tuesday.
A couple of weekends ago we had cool weather for a 28 mile Angeles Crest 100 training run from Islip Saddle to Chilao Flat. It was a bit windy and chilly at Islip Saddle, but once we were up and over the shoulder of Mt. Williamson the wind settled down and the weather for the remainder of the run was near perfect.
This was the second of four supported AC100 training runs, each covering a different section of the course. These organized runs account for just a tiny fraction of the total mileage a runner does to prepare for this event, and much of the mileage is done on the AC100 course.
Where is the AC100 course? Incorporating segments of iconic trails such as the Pacific Crest Trail, Silver Moccasin Trail and Gabrielino Trail, the AC100 starts in the mountain community of Wrightwood, California and ends in Altadena near JPL, traversing a large part of the San Gabriel Mountains.
Mountain weather — even Los Angeles County mountain weather — can be extremely varied and changeable. At about mile 18 the AC100 course reaches an elevation of more than 9,200′, near the summit of Mt. Baden-Powell. On the same day temperatures on the course can differ by 50 degrees or more. One section can be inundated by a flash flood while another is bone dry. During a Spring training run it might be 100 in the sun at Echo Mountain, while it is snowing on Baden-Powell.
The Mt. Wilson Towercam is usually pointed in the direction of the Angeles high country. When it is, it provides a great overview of about two-thirds of the AC100 course. The view extends from the top of the Acorn Trail at about mile 4 (in the distance on the far right), along the crest past Mt. Baden-Powell, Throop Peak, Twin Peaks and Waterman Mountain to Three Points at about mile 43. Chilao is hidden from view, but the Charlton Flat area and a section of Edison Road is visible on the left. Newcomb Saddle, at about mile 68, is on the lower right. Here’s an annotated Towercam image that shows the approximate location of these features.
Bill Westphal’s Altadena Weather & Webcam gives a lower elevation view of the San Gabriels, near the AC100 Finish. The view is NE toward the Sunset Ridge Trail and Mt. Lowe Road, around mile 93 or 94. The course goes from the right of the photo to the left, but is mostly hidden from view.
If you are willing to jump through some Java security hoops the Mountain Hardware Live Interactive Cam in Wrightwood is a couple blocks from the AC100 Start. It has views of downtown Wrightwood, Wright Mountain, the Heath Canyon landslide, Blue Ridge and several other locations. I temporarily enabled Java and followed the troubleshooting info linked on the web cam page. I’ve been able to get it to work on a desktop system using Firefox or Internet Explorer. Note that enabling Java and adding non-secure URLs to the Java exceptions list decreases the security of your computer.
Following are several Remote Automated Weather Stations (RAWS) and Weather Underground Personal Weather Stations (PWS) along or near the AC100 course, in order from Start to Finish.
It is important to note that the air temperature given by RAWS stations is the temperature inside a sun-shielded, ventilated enclosure 4-8 feet off the ground. Basically it’s the temperature in light shade. The temperature in full sun can be 15°F higher. I’ve found the “Fuel Temperature” to be a better gage of how hellish it’s going to be on exposed areas of trail. (The Fuel Temperature is the temperature of a ponderosa pine dowel in direct sun.)
Big Pines BPNC1 RAWS (6964′) – Off Hwy 2 near Mountain High Ski Area. Top of Mt. Baden-Powell can be 12+ degrees cooler and much more windy. Was 64°F at 6:54 a.m. for 2015 AC100. Fuel temp at 11:54 a.m. was 92°F.
Henninger Flats HNGC1 RAWS (2800′) – Approximately 0.8 miles WSW of Idlehour Aid (~3168′). Marine layer can increase humidity on this section of the course. Was 69-70°F from 4 a.m. to 7 a.m. for 2015 AC100. Fuel temp was 89°F by 11a.m.
Altadena KCAALTAD18 PWS (1214′) – Approximately 0.6 miles S of Finish. For 2015 AC100 temp ranged from 66°F at 2 a.m. to 63°F at sunrise. Temp was 79°F at 9 a.m., 82°F at 11 a.m., and 86°F at 1 p.m. Humidity was high with dew point about 70°F.
Illuminated by a just-risen sun, Goat Buttes reflected sharply on the lake’s surface. Ducks squabbled near some reeds and a bullfrog’s resonant croaking filled the canyon.
Part way through the Bulldog Loop, I’d paused for a moment at Century Lake in Malibu Creek State Park to enjoy the tranquility of the early morning. I snapped a photo and then noticed something very disturbing. The hundred year old coast redwoods across the lake looked brown.
Although coast redwoods have been planted in several areas of Southern California, they do not occur naturally here. The southernmost stand of naturally-occurring coast redwoods is about 200 miles north of Malibu Creek State Park in the Southern Redwood Botanical Area of Las Padres National Forest.
Redwoods have widespread, but shallow, root systems. Drought and warming temperatures are a worst case scenario for these trees, with the upper layer of soil being moisture-starved and baked.
Ironically the redwoods closest to the lake appear to be the most severely affected. This tree away from the lake on the Forest Trail appears to be in better shape, but it too is showing signs of stress.
Malibu Creek State Park isn’t the only locale in Southern California where redwoods are dying. According to this May 2015 San Gabriel Valley Tribune article, 15 redwoods were removed from Verdugo Park in Glendale, and redwoods in other areas of Southern California have also been affected.
As mentioned in an earlier post, the 2004 article “What’s up with the redwoods?” by James Downer, discusses a dramatic decline in coast redwoods planted in Ventura County and describes some of the problems that can affect this tree.
Drought and climate impacts are not limited to redwoods in Southern California. Endemic redwoods, particularly those in the southern extent of their range have also been significantly impacted.
Doing a little sleuthing using Yelp reviews of Switzer Falls, it looks like the creek had low sediment levels in early January 2014, but was heavily silted in mid-March 2014. Based on this, it appears that the initial sedimentation event occurred during the storms of February 26 – March 2, 2014, when nearby Opids Camp recorded 10.95 inches of rain.
The origin of the 2009 Station Fire was in the Arroyo Seco watershed and it was one of the most severely impacted. A question that comes to mind is why did the Arroyo Seco drainage produce such a high rate of stream sedimentation in the February-March 2014 rain event, but not in the very high flows of February 2010 and December 2010, and the moderately high flows of March 2011?
Some of the factors likely include vegetative cover, rainfall rate, recent rainfall history, the soil’s hydrophobicity, the soil support provided by degrading root systems, the magnitude of the peak flow and the shape of the stream discharge curve. Our multi-year drought has been an amplifying factor, further reducing vegetative cover and soil support.
Originally posted January 7, 2016 and rewritten to reflect the current rainfall totals for Downtown Los Angeles. Rain season totals have been updated as of March 31.
Based on 1981-2010 climate normals Downtown Los Angeles (USC) receives, on average, 1.04 inches of rain in November, 2.33 inches of rain in December, and 3. 12 inches in January. This past November Los Angeles recorded only 0.01 inch of rain, and in December only 0.57 inch. January rainfall was a few hundredths above normal at 3.17 inches.
The 2015-16 El Nino is one of the three strongest El Ninos in the past 65 years; the other two were 1982-83 and 1997-98. How does the amount of rain we’ve had so far this rainfall year compare to the other two? Is this El Nino failing to produce the expected amount of rainfall in Los Angeles?
On January 7, when this post was originally written, the rain year totals were in the same ballpark for the date as during the 1982-83 and 1997-98 El Ninos. That is no longer the case, and Los Angeles rainfall totals are falling far behind those other big El Ninos.
As of January 31 Downtown Los Angeles (USC) has recorded only 6.97 inches of rain for this rain year, which is 0.47 inch below normal. At this point during the 1982-83 El Nino Los Angeles had already recorded 12.98 inches of rain, and in the 1997-98 El Nino 9.15 inches. (See updates below.)
The good news is that the Sierra snowpack is above average. That helps with the water supply, but not so much with naturally-occurring local groundwater and other drought impacts in Southern California. It does help that the Los Angeles rain year total is nearly normal, but I’m still waiting to see running water in upper Las Virgenes Creek.
Remarkably, as of this morning, the medium range models are forecasting dry weather to predominate over the next 10 days or so and both the GFS and ECMWF show a mega-ridge of high pressure developing over the West Coast this weekend. We’ll see!
As of March 31 Downtown Los Angeles (USC) has recorded only 9.36 inches of rain for 2015-16 rain year, which is 68.5% of normal. At this point during the 1982-83 El Nino Los Angeles had already recorded 25.72 inches of rain, and in the 1997-98 El Nino 26.89 inches. All the data for the April 1 Sierra Snow Course Measurements are not available yet, but it looks like the snowpack will be around 85% of normal. In 1983 the weighted statewide average snowpack was 227% of normal and in 1998 it was 158% of normal.
For the most part the upper layer of clouds had been above Boney Mountain. Thin wisps of cloud had clung to the ridges in a couple of places, but the ceiling looked like it was going to remain above the peak.
Fog changes the mood and character of a place, particularly a place where airy views and an expansive mindset are the norm. Thoughts turn inward and perceptions more narrowly focused. The big picture becomes entirely virtual.
Earlier in the week the area had been drenched by more than two inches of rain. It had been damp overnight and water filled the profusion of irregular pockets covering the volcanic rock. The rock was plastered with a patchwork of bright green moss and gray-green lichen. Saturated with water, the moss was slippery as ice. I climbed with extra care, especially on the steeper sections.
Where soil collected on tiered steps, obovate leaves of shooting-star and other annuals sprouted, presaging a show of the purple and yellow wildflowers. Chalk liveforever relished the moisture, its drought-scarred leaves rehydrating and recovering.
Higher on the ridge the intricate green foliage of red shanks, still recovering from the 2013 Springs Fire, was heavily-beaded with water. Brushing against it was like being sprayed with ice-cold water.
The last couple of days I’d been checking the weather models to try and get an idea of when the cold front might reach Pt. Mugu State Park. Projections ranged from around 10:00 AM to about 1:00 PM.
A group of us were doing an annual end of the year trail run and scramble over Boney Mountain to the Backbone Trail, and then returning by various routes to the Wendy Drive trailhead. Along the way there are great views of the Boney Mountain Wilderness, Channel Islands, Conejo Valley and Ventura Mountains, but you can’t see very far from inside of a cloud.
It turned out clouds would not be a problem. At least not the first half of the day. When I pulled into the parking area at Wendy Drive the front was little more than a white smudge on the western horizon. The sky was clear and it remained clear the entire time we worked up Boney’s Western Ridge. Everyone enjoyed scrambling up the gullies and rocks to the top of the mountain and then over to Tri Peaks.
We’d reached Tri Peaks about 40 minutes ago. From there I’d run over to Sandstone Peak, the highest peak in the Santa Monica Mountains. From this panoramic vantage point I could see the front was still well to the west, near Santa Barbara. This gave me some time. I was prepared for rain, but didn’t want to miss the wonderful scenery running down the Chamberlain Trail, over to Serrano Valley, and through Serrano Canyon.
Over the remainder of the run I watched as cirrus clouds ahead of the front gradually muted the sun, mid-level clouds began to develop over the peaks, and the wind became more gusty and fitful. Later in the run the clouds started to lower and thicken and the temperature dropped. Eventually it began to smell like rain.
As I crested the hill on Danielson Road I felt a cold drop of rain on my arm and then another on the back of a leg. Clouds covered the sky, and to the west showers draped the ridges and filled the canyons. The front and I were racing the last mile to the trailhead, and I knew who had won.
Due in part to El Nino and the Madden-Julian Oscillation (MJO) Southern California jump-started the 2015-16 rain season with above average rainfall in July and September.
Last year the NWS changed the WATER Year to October 1 – September 30, but the RAINFALL Year remains July 1 – June 30, as it’s been for decades.
Below is the monthly tabulation of rainfall for Downtown Los Angeles (USC) for the 2015-16 Rainfall Year, along with what is considered normal for the month.
Downtown Los Angeles Rainfall
So far this rainfall year Downtown Los Angeles (USC) has recorded 3.23 inches. Even with November as dry as it’s been we’re still more than an inch above normal for the rainfall year — about 1.46 inches above normal as of November 25.
Over the next couple of weeks the medium range models and other tools aren’t especially bullish on our chances for a good, soaking rainstorm in Southern California. Longer term guidance suggests an improving chance of precipitation as December progresses, and above average precipitation in January and February. We’ll see!
The title photo is from November 3. It shows a band of thunderstorms that moved southward across the San Fernando Valley and into the Santa Monica Mountains. The band produced cloud to ground lightning strikes and some heavy showers. Saddle Peak is in the distance on the left. The shower activity in the distance on the right is in the area of Kanan Rd. and the 101 Frwy.
Summits that can be accessed by trail are usually busy places, especially in good weather. That was certainly the case this morning. Each of us had encountered someone we knew on or near San Jacinto’s rocky summit.
It seemed everyone on the peak was doing a different adventure. One hiker mentioned he had run out of food at Wellman Divide. That seemed strange until he explained he was doing the “8000 Meter Challenge” — ascending Baldy, Gorgonio and San Jacinto consecutively in 24 hours. The 8000 meters refers to the (approximate) cumulative gain and loss when doing the three peaks. In round numbers Baldy via the Ski Hut would be about 2375 meters of gain+loss, Gorgonio via Vivian Creek 3350 meters and San Jacinto via the Tram about 1500 meters. If you skip the Tram and do San Jacinto from Idyllwild the gain+loss is about 2680 meters.
An ultrarunning friend that reached the summit shortly after we did was doing Cactus to Clouds to Cactus (C2C2C). This arduous route starts in Palm Springs at an elevation of about 460 feet and climbs all the way to the summit of San Jacinto at about 10,834 feet. Including a couple of short downhills along the way, the total elevation gain is around 10,800 feet. Round trip that works out to about 6600 meters of gain+loss.
Ann, Telma and I were doing a route I’ve enjoyed for many years — ascending San Jacinto from the Tram and then running down to the fire lookout on Tahquitz Peak. The route has excellent running and (on a clear day) hundred-mile vistas. The views of Tahquitz and Suicide Rocks bring to mind many fine days spent with friends at these superb rock climbing areas.
When we got our wilderness permit at the Long Valley Ranger Station the ranger had warned us about 45 mph winds and cold temps on the summit. The strong winds had been forecast to moderate before sunrise and the forecast was spot on. The weather on the summit was near perfect — warm in the sun and cool in the shade with light winds.
After ascending San Jacinto we returned to Wellman Divide and then descended the Wellman Divide Trail and PCT to Saddle Junction. From Saddle Junction it is only a couple of (mostly uphill) miles to Tahquitz Peak. This Google Earth image shows my GPS track from Wellman Divide to Tahquitz Peak and back.
A dozen or so hikers were enjoying the warm sun and great weather at the lookout. As always, the fire lookout host was friendly and informative, answering questions about the lookout’s equipment and surrounding landmarks. Want to become a volunteer host? Check this page.
My usual return route from Tahquitz Peak is to go back to Saddle Junction and then follow the Willow Springs Trail to Hidden Lake Divide. With the Willow Springs Trail closed due to the 2013 Mountain Fire it’s necessary to climb back up to Wellman Divide and then descend to the Tram from there. This adds about a mile and 800′ of gain to the usual route. Although we had descended it earlier in the day, the trail going up to Wellman Divide had a different feel to it, and the out and back wasn’t nearly as onerous as I thought it might be.
About an hour after topping out at Wellman Divide we were back at the Long Valley Ranger Station and not long after that on the Tram and headed down the mountain. I smiled as the decades-old recording in the tram car began, “You’ve had a great day…”