Bishop Pass / Dusy Basin Area in Late September / Early October

For general summer use in the west I have a 30F comfort rated bag. As a rule thru September (which this could be called) I bring that. But I would also be able to switch to my shoulder season setup if the forecast is unseasonably cold

You can day hike over Thunderbolt Col and back via Knapsack. Moderate off trail stuff

Or bag a peak. Mt Sill is a 14er and arguably the simplest of the big ones in the Palisade group. A medium to tough day from Dusy, depending on your background

A loop back to South Lake over two nights seems hard to conjure. The good news is that the area  around Dusy basin is spectacular. You could easily keep yourself entertained day hiking for two days.

I’d  personally want a warmer bag than 30% at that time of year.

>I’d personally want a warmer bag than 30% at that time of year.

I’m thinking about one of those Enlightened Equipment Accomplice quilts, but I’m not sure if 20 is low enough…or 10.

Our current quilt is a Thermarest Vela rated 32F, which I don’t think is gonna cut it.

jscott, I did say comfort rated or true to temp when mentioning my 30°F bag. Since that is not EE I’m unsure what the correct translation is. 20°F? Deeper? That would bring us closer to talking about the same thing.

Assigned ratings are tricky, even if the manufacturer adheres to EN Standards.

So for Jeb who’s shopping for sleep gear, here’s a baseline I found useful: A healthy solo quilt user identifying as male and of average size will benefit from 450g, or one pound, of 900FP goose down to mostly experience comfort at 20°F.

If the shopper is also nerdy enough to recognize a good design that will help.

The most valuable tools for sifting thru the market are conducting spec comparisons (fill weight, fill power, accurate sizing, total weight, features such as differential cut, draft collars) between makers; and reading unaffiliated user feedback on threads, especially on large platforms like reddit UL.

Data which should be viewed with skepticism are review sites (OGL, etc), YouTubers, and submitted reviews on the manufacturers site.

I guess the more direct question to answer is what overnight temps at the end of september / beginning of october are within the range to be prepared for. Teens? 20s? Single digits? Not sure where if there’s a good place to look this up.

I don’t have late season experience in the Sierras but if I was planning a two night trip in that time frame I would want to have a couple of options in my gear closet so that I could make a last minute decision based on weather reports.

Recall that Dusy Basin is at 11,600 feet altitude. there’s zero tree coverage. It’s gonna be cold at night in late September.

I’d want to be prepared for 10F nights that time of year… but as to bag rating, so much depends on if you are a cold or warm sleeper… huge variation from person to person. Weather forecasts are a must… any time of year, but especially then, but unlikely you will find anything at is specifically for that spot.

Weather Forecast… go to NOAA for Bishop, CA…. scroll down to the map, move the target area from Bishop up to Dusy Basin (you can zoom in and move around the map for detail to find Dusy), hit ‘enter’, and look at the NOAA forecast for Dusy Basin… can scroll down again and click on the ‘hourly weather forecast’ chart… that will bring up an hour by hour forecast for two days…. and you can click on next 2 days… BUT… the forecasts are only interpolated for location and altitude; they will not actually be specifically crafted for Dusy… they will not be able to predict the micro climate at Dusy Basin… some basins are colder as they act like a ‘cold sink’ at night. That time of year better to be too warm than too cold…

The other thing for weather might be… a week or so ahead start watching the forecasts for Sacramento and/or Fresno… if you see a forecast for a sharp drop or rise in temps or a weather front coming in, you can figure that will affect Dusy Basin within a day or two at the most…. If you see a 20F drop in temps or a 20F rise, that will also affect Dusy… or even start watching the forecasts for the PNW/Seattle for an even longer range indication… even now in the summer when the temps drop in Seattle about two  days latter we feel it here in CA…

I often hike in the Sierra Nevada in late September/early October as it’s my favorite time to be in the range as the Aspens are a nice color, no bugs, and water crossings are low. Snow is possible.  I hiked the JMT a couple of years ago and finished on Mt Whitney on Oct.6.  I started in snow, but had great weather the rest of the trip; nights were cold of course.  You never really know what you’ll get.

I always go hiking with a 20F degree bag there in September and with the layers to hike in the same temperatures. If needed, the extra layers can be worn to bed to give you more margin.

Temperatures will likely be below freezing at night and low 20’s is common. A different location may have different temperatures in the same area.  I doubt you’ll see anything below the upper teens unless you are in a wind tunnel with a good wind chill.  If there is wind, try to find some shelter behind boulders, etc, or consider moving on to a better spot.

Dusy Basin end of September, low 20’s and possibly teens at night.  Also, be prepared for snow anywhere.

As to loops, suggest camp both nights in Dusy Basin and day hiking an out and back or loop into Palisades Basin.  If your off trail experience is limited, there is enough left of the old trail over Knapsack Pass to make it a great introduction.  (tip: from the top of Knapsack the trail goes to the left and climbs a bit before descending into the basin).

Yeah I think that sounds like a good plan. That’s probably what we’ll do. Thanks.

Forecast is looking pretty warm right now

Unless I’m looking at the wrong forecast, overnight lows in the low 40s.

We’re having unusually warm weather. Still… not sure I would trust a 40F forecast for Dusy… forecast is similar for much lower elevations, so suspicious of 40F for Dusy…

This trip ended up being completely amazing by the way. Thanks for all the help!

Please share details and pics!

Jeb, yes please give us some details and pics if you have them. I like revisiting this area vicariously.

Oh sure, here’s a couple (I actually sadly didn’t take many pictures, I had my phone off in my bag most of the time)

(for some reason every time I hit submit it says “Error: your reply cannot be empty” so I’m going to try posting this and then adding another post below)

The weather was perfect. Little chilly at night, but clear and sunny during the day. No bugs, great hiking weather. Can’t wait to do it again!