April Flowers Bringing It

The Merced River approaches 'minor flood' stage tonight, with the previous two night's flows being near 5300 cfs, which is roughly double the average peak spring volume. Valley meadows are wet, some trails are under water, some campsites unusable, and it's a great time to be a duck. While exciting, this is the normal and predictable outcome from a winter that brought the Merced watershed 153% of average snowpack water content as of 1 April (and 176% in the Tuolumne watershed). The waterfalls are ripping right now. You may recall that (after vehicle accidents) swiftwater is the number one factor for visitor fatalities in Yosemite; respect the water. April has been warmer than usual (only one day of wist ice [frazil] in its typically most productive month) and we wonder if peak runoff has come 3-4 weeks earlier than the late May average.

There is still a huge quantity of snow at 7000' and above. While we did have some warm storms this winter that brought rain to high elevations, we had far more storms that delivered snow down to 2000'. Several recent SAR call-outs have resulted from people getting up into deep snow where they didn't expect it. Some have been getting their intel from various posts/photos about nice April hikes that others did last year - that was a very dry winter. The Fourmile Trail and the JMT below Nevada Fall (ice cut) are still closed and dangerous. The High Sierra Camps won't open this season. Expect stream crossings to be challenging and snow to persist well into mid-summer in the high country.

Dogwood flowers are at the puppy stage in Yosemite Valley. Tanagers, orioles and grosbeaks are singing and shining brightly. Peregrines are at their eyries. The green dragons are rolling. "This grand show is eternal..."

The burst of spring

I encountered my first Western Tanager of the year on Monday's Conservancy bird walk - just moments after a participant asked about them. It was a stunning, bright male in the black oaks in front of the visitor center - lots of exclamations from all present. Since then, more males have arrived and are singing in Yosemite Valley. This morning we had the triple feature of the bright neo-tropicals when within a short time we also saw the male Black-headed Grosbeak and Bullock's Oriole. Surprises on Monday were the Lark Sparrow feeding on the gravel trail along Cook's Meadow and the Western Kingbird sallying out from the black oak canopy over the meadow. This morning we had a decent look at Vaux's Swifts.
Those black oaks are pale green with dangling flowers now and a few leaves are starting to emerge. The early dogwood below the former diversion dam site, along 140 has 'blooms' almost 3 inches across which are almost fully white. Most Valley dogwoods are still pale green - they're more than a week behind an average spring schedule.
The Merced River has leapt in volume with the warm weather this week; it's doubled in volume in the past five days. This morning it had already exceeded the average springtime peak - and there are still a few weeks of potential increase to the average high flow date. Low-lying Valley trails are starting to get wet, but there's no real flooding yet. (Last year peak flow reached 2.5 times what it is now!)

Tanager Swarm

This morning's YA birdwalk featured good looks at at least a dozen male tanagers in the black oaks near the Valley Visitor Center. The birds were quite silent, we saw no females, but the guys gave us some lively, near eye-level views of their brightest tropical plumage with the morning sun behind us. I've seen similar concentrations of male tanagers before; once I counted 125 streaming through the oaks near the medical clinic, all moving east together. My eyes hurt for some time afterward from all that color.
The trail beyond Mirror Lake has some muddy, wet stretches, but few people. The view from just ten switchbacks up the Snow Creek Trail is remarkable, with melting snow pouring down from Clouds Rest. In bloom: Nemophila, Phacelia, Castilleja, Viola, banks of Claytonia, and of course, Cornus.
The Tuolumne Grove has about 50% snow cover, with depths of less than a meter. It's melting out quickly and the big trees are drinking big from the melting snowpack. Did we see a goshawk flash by?

Dogwood Day Afternoon

Some late cold weather has stalled the dogwood blooms in Yosemite Valley a little this season; all but a few flowers are still green. It's my sense that the emerging bracts are 3-5 days behind a 'normal' spring's phenology. The one early tree that locals first look for is a few hundred yards below the former diversion dam on Highway 140. Its display is mostly white, but the bracts are still not full-sized.
This morning's birdwalk included the triple feature of three of our brightest neotropical migrants: oriole, grosbeak and tanager. The latter two were on the same flowery oak branch at one point. Best surprise: a California ground squirrel a good 30 feet up in a black oak near the Administration building.
Claytonia and Nemophila are adding some color (white) to the ground cover in the Valley this week.
Expected warmth for the next few days should bring the dogwoods into full glory by next weekend, and it'll bring the river up well over 2000 cfs again.

Black and White TV

A turkey vulture flew over Yosemite Village, about 100 meters up, at 7:30 this morning. Especially on this cold, snowy sun-up, I take this to mean that the vulture roosted in Yosemite Valley rather than soaring upcanyon on thermals from lower elevation - something new for our neighborhood. Will condors be next?
More frazil ice formed up in Yosemite Creek this morning, covering all the channels and scouring more forest terrain of its natural duff. A good volume of slurry flowed into the Merced River. Frazil flowed in Ribbon Creek, too, and it went downstream of Northside Drive for the first time this season.
The handful of planted redbuds in Yosemite Valley are blooming; they endured a taste of snow overnight. Dogwoods are making progress, with some 'blossoms' up to 10 cm across and just starting to turn white.