Wednesday, September 30, 2009

Another Great Fall?

Fall seems to be progressing at a typical pace in the eastern Sierra. You can find links to various fall color reports in Dan Mitchell’s blog.

Autumn of 2007 was exceptional. The dogwoods around the 5000 to 6000 foot elevation in Yosemite were unusually red, as you can see in the photo above, made along Highway 120 west of Crane Flat in October of 2007. A week after making that image I met a ranger on my way down to the Tuolumne Grove and asked her about the color. She said that conditions were perfect, since we had had a warm September followed by a cool October.

We’ve had a warm September this year, but yesterday the temperatures dropped off a cliff. Monday’s high in Yosemite Valley was 87, Tuesday’s 65. Thursday and Friday are supposed to be slightly warmer, but then the weather is expected to cool off again. Could we have another great fall?

I’ve tried to find information that would back up the ranger’s claim that a warm September followed by a cool October brings good fall color. A Wikipedia entry discusses the anthocyanins that produce reds and purples, and says that “when the days of autumn are bright and cool, and the nights are chilly but not freezing, the brightest colorations usually develop,” but nothing about the effect of warm temperatures followed by cooler weather. If anyone can point to better sources of information about this topic, please let me know! Otherwise we’ll just have to wait and see.


  1. Hi,

    This might help.


  2. Michael, thanks for mentioning the fall conditions coverage at my blog!

    Speaking of fall, last fall I had the most incredible coincidence of conditions in the Valley. I was there for 2 1/2 days right at the beginning of November... and had glorious rain the whole time! I'm sure you know the wonderful effects of the moisture and the overcast in the Valley, but the most unusual experience was having fall colors and full rivers and waterfalls at the same time.


  3. Thanks for the link Dave - very interesting article. Both this article and the Wikipedia entry say that the best color comes from sunny days followed by cool nights, although nothing about a stretch of warm weather followed by cooler temps per se. But we are having sunny days and cool nights right now, so maybe that bodes well. In any case I have a good feeling about this fall...

  4. You're welcome Dan. I remember that rain in early November last year. I even thought I might get a Horsetail Fall photo since there was plenty of water in it, although it was past the fall window for the best light. But alas the sun didn't cooperate anyway. And yes, I certainly appreciate the way moisture brings out subtle colors in leaves, moss, tree trunks, etc. My Oak Trees and Swan Slab image was made under just those conditions:

    Anyway, glad you had such a great experience last fall, and to hear that you appreciate early November in Yosemite. My favorite time in the Valley - fall color, interesting weather changes, usually few visitors - magic! Maybe I'll see you out there this fall.

  5. Last year I planned a trip to the East Side on Week 3 of October. Then, it snowed/rained right before my trip. I got some OK aspen shots, but most the leaves had turned brown or black. Got some great shots of evening light on rock monuments off 120 though! I guess an attude to take is - dream and hope for brilliant fall color and have a back-up plan
    ;-). I'm planning the trip again this year. OK everyone - Let's hope and dream BRILLIANT COLOR!!

  6. Last fall was strange, especially on the east side. It was very warm until almost mid-October, and the aspens were slow to turn. Then on October 10th a front descended from the north and dumped six inches of snow in Lee Vining Canyon. I was over there teaching a workshop, and we got some great photos of snow-covered aspens.

    I came back a couple weeks later and found, like you, that most of the trees were bare or had brown leaves, but the June Lake loop had somehow escaped the damage and was beautiful.

    Anyway, I'm with you, and hoping and dreaming for great color too.


Note: Only a member of this blog may post a comment.