High Sierra Topix

I am planning a multi-month walk this coming summer in our favorite range, and wonder what when the first big snow tends to hit in the fall--what might be considered a season ender if you don't plan to continue equipped for steady and/or deep snow. What has your experience been? Any suggestions for historical summaries - typical and record highs/lows, precip, and so forth that reasonably represent the Sierra backcountry as opposed to Bishop or Mammoth?

Thanks!

First of all you must know that it can vary year to year. Personal experience; I backpack regularly in October in the high country - 10,500 and up. Most trips I get a light snowfall (afternoon thunderstorm) that melts off fast except on north facing or shaded slopes. In October, I have never encountered enough snow to end a trip, but I have had enough snow to make north facing talus slopes treacherous and scary. I have done a couple of trips in November in dry years and found conditions to be similar but even colder to what I expect by Mid October. But that was a dry year, I would imagine that November often sees significant snow even early in the month.

Second half of October can bring in some heavy snow, but as Brian wrote
it varies.
I've been up in October with no snow fall, and then another year I got dumped
on by several feet in 2 days up near Emerald Lake out of Lake Sabrina.
If you are going out in October just be prepared for anything especially
the second half of the month.

Try this: http://www.raws.dri.edu/

Can't remember if I got the link or not from HST. Seems like it was here. If you have time to digest it.

In the last 8-10 years, I have had snow on three trips now. Seems just like my early days of bping, if it rained I headed out. Now it is snow, so I will make adjustments to it too. With snow though, usually comes cold too and I know I won't be able to function if I get too cold or wet, especially my hands. Last year in Yosemite in early Oct., I hit four inches of snow the second day out around the Sunrise Camp area. Weather turned great after that. When I got back to my low riding car, I had a flyer on it saying the Tioga Pass road was closed. By the time I left, the snow had melted off around TM so I was able to head home over Tioga Pass.

I've backed off from October trips. I'm not a snow fan or an extreme cold fan when fishing, except when i'm on the way out and i know i can do it safely. I plan my yosemite trips a week after the high sierra camps shut down. Less people, hungry fish. I should note that fishing get's a lot tougher when your rod guides are constantly freezing over (if you fish.)

We still do get snowed on after the 20th of sept, but it's generally a short snowfall/flurries and we can be on a trail at that point if it get's rough.

Russ

I can't recall a snowfall in September big enough to cause real problems unless you're off trail and have to hop talus to get out - a few inches of snow on a trail is no big deal, a few inches of snow on talus can be dangerous as all get out. October is often very nice, but you can get a couple feet sometimes in october, and that can change the game right quick. I personally don't trust any weather forecast past about 4 or 5 days at that time of year, so I wouldn't plan a trip after about the first week of October that required me to get from Point A to Point B in a certain number of days, unless it was a short trip and I could go when the next few days looked to be good. September I would trust. On the other hand, If you can allow plenty of time and are prepared and equipped for a big snowfall if it comes, October is a great time to be out there and enjoy your own private mountains.

Wow!!

Brings back memories. I did my thesis on determining the probability of a fire ending event in the Caribou Wilderness. (A fire ending event is a precipitation event sufficient to stop the spread of a natural occurring fire -- or a 'let burn' in the lay parlance).

Without going into the techo jargon and way more weather and fire modeling I want to list here, Sept 20 in the Caribou wilderness is the 50th percentile date for sufficient rainfall. This is not the first snowfall that shuts down the backcountry, just the first significantly wetting storm. If you want the probability by date I can provide it.

When i used to Mule Deer hunt in Southern Utah, I got trapped (in october) on a lava bed/scree pile under about 8" of snow. 8 inches in i think 4 hours as that's about how long it took for me to get up where i thought the deer were. I fell through once and ripped the leather on my boot right down to the gortex lining. I was really lucky. Still kinda upset i ruined a great pair of boots.

October is great for the crispness of the air (in the sierras), but it also requires one to carry more warmth. My batteries dont seem to like October either.

Russ

Many thanks for the collective experience and wisdom of the group--I really appreciate it!

Often there is bad weather on Labor Day, some communist thing I suppose:)

Please keep in mind that snow is not going to be your danger key. Wet is. If it is a classic fall wet snow, or rain, you must stay dry.

Often folks have not made the gear switch for fall weather. Make sure you can stay dry.

When I lived in Truckee we often skied at Mt Rose Meadows in September, a few inches of snow on DG.

I did a ski tour from Mt Rose to Kings Beach in the middle of October 10 years ago, three to four feet of snow on the ground.

That much snow is a real problem without skis or sno shoes.

A few years ago I recollect some hikers caught by an early season snow at Rae Lakes, they got cold and wet, which is a bad thing. I do not recollect more details, perhaps someone else does.