Weather and water update 25th September 2026

Tropical moisture emanating from the south generated welcome thunderstorms in the middle of the day on Thursday 24th September, although the impacts were highly localized. Idyllwild (at 5550 ft) received only 0.03 inch of rain, although a torrential downpour was reported in Mountain Center (4500 ft). There was minimal evidence of rainfall throughout the trails at mid elevations, but intense rain above 9000 ft included 0.48 inch at Wellman’s Cienega (9300 ft) and a brief but spectacular mixed rain/hail storm above 9900 ft produced 0.98 inch at San Jacinto Peak, with widespread accumulations of hail remaining into the following morning (photos below).

Temperatures are currently trending above seasonal (well above average for overnight lows), although 27th-29th are forecast to be cooler. Conditions warm yet again thereafter, and temperatures in the first week of October are expected to be well above seasonal. Temperatures at the highest elevations now feel distinctly autumnal, especially on the breeziest days, but are actually averaging generally above seasonal. There is the possibility of light precipitation on Monday 28th.

Despite the moderate tropical rains in early September, water flows quickly returned to their late August levels. With the additional rainfall on 24th, higher elevation water sources (>9000 ft) have very briefly improved flow rates, but again these improvements will be brief.

At this time main springs and creeks largely continue to flow, albeit weakly, rates having dropped dramatically since July. Ephemeral sources are dry, while “perennial” water sources remain at low flow rates for the time of year. Key sources such as the pipe in Round Valley (flow rate 0.6 L/min on 21st September), the North Fork crossing of Deer Springs Trail (6.5L/min), and the creek in Little Round Valley, are flowing. Wellman’s Cienega is flowing weakly, especially from mid morning onwards (flow rate 0.5L/min on 22nd September). The Deer Springs crossing at PCT Mile 185.4 is functionally dry.

Water is flowing weakly but reliably in Tahquitz Creek near its source at PCT Mile 177 and again further downstream at the north end of Little Tahquitz Meadow (although it is dry between those two locations). Strawberry Cienega is dry. Willow Creek is flowing very gently where it is crossed by Willow Creek Trail, and further downstream where it is crossed by the “King Trail”. Middle Spring on Devil’s Slide Trail is now functionally dry for hikers, but I continue to maintain a tiny pool suitable for thirsty dogs and wildlife. The North Fork of the San Jacinto River is dry where it crosses Seven Pines Trail and further downstream where it crosses Dark Canyon Road. On the Desert Divide, Live Oak Spring is flowing weakly, but both Cedar and Apache springs are no longer reliable.

The scheduled annual maintenance closure of Palm Springs Aerial Tramway started Tuesday 8th September, with a tentative reopening on Monday 5th October 2026.

Be rattlesnake aware. As temperatures have cooled, observations have become less frequent, especially above 8000 ft, but sun-exposed mid elevation areas such as Devil’s Slide Trail, South Ridge Trail, lower Deer Springs and lower Marion Mountain trails, and around Suicide Rock, have continued to record rattlesnakes on warm days throughout late September. Above about 5000 ft elevation, the venom of Southern Pacific Rattlesnakes (Crotalus oreganus helleri) in the San Jacinto mountains is predominantly neurotoxic, almost always fatal for dogs and sometimes for humans (see my long read article linked here for further information describing the unprecedented survival of our dog Anabel after a July 2020 neurotoxic bite).

Be bear aware. Although rarely reported, up to six individually identifiable Black Bears have been observed in the San Jacinto mountains in the past decade. Of these, one with an ear tag has been here since 2017 and was seen repeatedly in 2025 (see, for example, my video from 14th September 2025 linked here). Another individual was fitted with a satellite collar in April 2026, and in just one month ranged widely from 8500 ft on the north side of San Jacinto Peak south into the Santa Rosa Mountains (per CDFW). There have been no reports of negative interactions with humans in the high country, at or near wilderness campsites, or on trails.

Dark Canyon campground has not reopened in 2026 due to staffing/budget issues, although Dark Canyon Road (the access to Seven Pines trailhead) has remained open all year.

Following superficial grading late last year, Black Mountain Road (4S01) is in slightly better condition than in 2025, but remains far rougher than in June 2020, the last time it was comprehensively graded. South Ridge Road is in poor condition (although not as bad as 2019) and generally requires a high clearance and/or AWD/4WD vehicle to reach the South Ridge trailhead at the top of the road.

Daily survey hikes by the Trail Report year-round in the San Jacinto mountains include multiple routes to the highest peaks including San Jacinto Peak typically 2-3 times per week (but almost daily during and following storm conditions), Tahquitz Peak and area at least once per week, plus a wide variety of other trails on intervening days.

The equinoctal sunrise as seen from San Jacinto Peak, 22nd September 2026.

WEATHER

After persistently hot weather in July and August, cooler conditions prevailed from 30th August into early September. Temperatures were around seasonal for the first few days of September, before rising yet again to above average.

Tropical Storm Marie (briefly Hurricane Marie) tracking offshore far to the south-west of our region generated moderate rainfall on Sunday 6th, with impressive totals of 1.17 inches at San Jacinto Peak, 0.97 inch at Wellman’s Cienega (9300 ft), and 0.55 inch in Idyllwild (at 5550 ft). Very light patchy drizzle on 7th then turned into a dramatic but brief thunderstorm with heavy hail in the high country on Tuesday 8th. This moisture, while still very much tropical in origin, was not directly associated with Marie, but was being drawn north directly from Baja. At San Jacinto Peak, a further 0.41 inch fell in just an hour in the afternoon on 8th.

Dry, mild weather continued for much of September, until the localized thunderstorms on 24th as described above. With the exception of brief cooling on 27th-29th, forecast temperatures for the remainder of September and well into the first week of October are expected to be well above seasonal. At this time there is no significant precipitation forecast for this region from the several hurricanes/tropical storms active in the eastern Pacific to our south and south-west.

At San Jacinto Peak (10,809 ft/3295 m) on Friday 25th September 2026 at 0830 the air temperature was 57.1°F (14°C), with a windchill temperature of 44.6°F (7°C), 65% relative humidity, and an intermittent SSW breeze sustained at 0 mph gusting to 3.3 mph.

At the Peak on Tuesday 22nd September 2026 at 0650 the air temperature was 40.9°F (5°C), with a windchill temperature of 32.2°F (0°C), 33% relative humidity, and a steady NW wind sustained at 8 mph gusting to 11.9 mph.

At the Peak on Monday 21st September 2026 at 1020 the air temperature was 49.8°F (10°C), with a windchill temperature of 39.0°F (4°C), 48% relative humidity, and a fresh due South wind sustained at 8 mph gusting to 13.6 mph.

Remnants of the hail storm from the day before, early morning 25th September 2026. Above, my tracks through accumulated hail (doing a good impression of a snow patch) at about 10,200 ft on the Peak Trail, and below, a close-up of the constituent hail stones averaging 0.25 inch diameter.

TRAIL CONDITIONS

Current water conditions are summarized in the paragraphs in the introduction above.

The first comprehensive trail trimming in decades is being undertaken by the Trail Report this year on the upper Peak Trail. Unmanaged chinquapin overgrowth had narrowed the trail to just 10-12 inches wide in places, which is problematic year-round but especially in winter conditions (example photos in prior reports since June).

Deer Springs Trail from the trailhead to Little Round Valley was cleared of the handful of blowdowns from last winter by the Trail Report.

Trail maintenance work by USFS and State Park volunteers earlier this year cleared Willow Creek Trail of blowdowns from last winter. Brush trimming work was undertaken on both the USFS and State Park sections of the trail in late July, although it was much more limited on the State Park section, and the upper switchbacks closer to Hidden Divide remain badly overgrown in places.

The Caramba Trail from near Reeds Meadow through Laws Camp and on to Caramba, and the Cedar Trail from Willow Creek Trail to Laws, are euphemistically (and perhaps dangerously) described by the Forest Service as “not maintained”. In reality both trails have been abandoned for more than a decade and no longer exist. They are so heavily overgrown, largely with dense whitethorn which obscures several hundred downed trees, that hikers should not attempt to follow them (regardless of how much you may trust any particular app).

An informal use trail to Laws is much more direct, generally well maintained, and avoids the bushwhacking of the abandoned trails (some local Idyllwild hikers dubbed it the “King Trail” when I established the route in 2019). It leaves Willow Creek Trail exactly 1.0 mile from Saddle Junction, 0.46 mile from the Skunk Cabbage turning (trailhead at N 33.7796, W 116.6590). The route is marked with cairns (and subtle flagging to aid USFS work crews) and descends following former deer trails for 1.2 miles, meeting Willow Creek about 0.15 mile upstream from the site of the historic Laws Camp (the remains of which were destroyed by the 2013 Mountain Fire and subsequent flood and treefall damage). Blowdowns from this winter have already been removed by the Trail Report, and the huge pine tree that fell in late 2024 was kindly removed by Forest Service volunteers in May 2026.

East from Laws the old Caramba Trail is initially heavily obscured by blowdowns and thick regrowth, but the easternmost 1.5 miles closest to Caramba camp is often well marked with cairns placed by myself and others. Much of the old trail rock work is visible in places. The first mile east of Laws is currently marked largely along the former trail route with orange flagging (for use by USFS work crews), although it is not recommended to follow this in some areas as it goes directly through blowdowns and obstructive vegetation, not around them.

Work to rehabilitate the original Caramba Trail started in June this year – combining the Trail Report, other volunteers, and Forest Service employees – almost exactly 13 years after it burned in the Mountain Fire. Unsurprisingly it is proving to be a very slow process and it is possible that 2-3 years of work may be required to fully rehabilitate the old trail routes. Please do not remove, move, or (as described above) attempt to follow, flagging in this area which has been placed to guide USFS work crews.

The Trail Report “adopted” Seven Pines Trail as a priority for maintenance work due to a disproportionate number of lost hiker rescues (with the agencies evidently no longer maintaining the route). In the past seven years we have removed 101 downed trees and the trail is largely trimmed and cleared annually. Thankfully only two large blowdowns affected the trail this past winter, and both now have very easy workarounds. Although our work has restored this delightful trail to its best condition in decades, Seven Pines remains a genuine wilderness trail very unlike the wider, bare, obvious routes of, for example, Devil’s Slide or Marion Mountain trails. Cautious navigation remains invaluable for those without extensive experience of hiking this trail.

Spitler Peak Trail is clear of treefall hazards, despite having been decimated by about 65 new blowdowns in mid February storms. In February-March the Trail Report cut almost all of these, bringing to 235 the number of trees we have removed from this trail in the past seven years. The remaining four large cedars were removed by Forest Service at the end of March.

The San Jacinto Trail Report celebrates ten years of operation in 2026. The Report has helped tens of thousands of hikers, and saved multiple lives, both directly and indirectly. Since the Report became established online, snow/ice rescues in the San Jacinto Mountains have dropped 82%, with an additional benefit of saving Riverside County hundreds of thousands of dollars. While all time is volunteered, the Report uses small private donations to help cover operating costs. Donations keep the Report available to all, free from advertising or paywalls, and independent from agencies. If you have found this Report useful, please consider using this link to the Donate page. Thank you very much for your support.

The best-known of the springs at the northern end of Wellman’s Cienega (9300 ft) flowing gently, early morning 25th September 2026. Flow is reasonable to mid morning, but weakens rapidly thereafter (0.6L/min on 25th, expected to halve over the following week).

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