Nightime Temps in the Sierra

“Hello everybody. I will be on the JMT, North to South from August 20 until about October 1. Just takin' my time... Anyway, it's been 41 years since I last did this which might lend a clue as to my age and also to my mental condition to wait so long to do it again. What can I expect in the way of night temps? I want to pack as light as possible (sleeping bag included).”

“Temps should be mild, into the low 40's. That being said you need to be prepared for the worst. I've awakened to heavy frost many mornings in August and been hailed on in July.”

“I would say it is more likely to have nice, albeit crisp, weather in September than to have bad weather, but you are definitely getting close to "winter" at altitude when you get close to October. I got 4 inches of snow at 10,000 feet on October 15 a couple years ago on the eastern slope of the Sierras (about 10 air miles east of the JMT) - the western and central parts got 3-4 feet in the same storm and lots of people had to be rescued.”

“When Mel, SARboy, and I came down off of Sheperds Pass on Sept 2nd in 2000 it was blowing about 35 mph and snowing sideways. That was a cold day. Be prepared.”

“IMHO, when you are in the Sierras for any length of time, you need to be prepared for rain, sleet, and freezing temps anytime.

Solitary - Remember the first Llama trip when we got caught in the hailstorm in Humphrey's Basin in August? That's when I had to invent my boot dryer!
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“and I've experienced temps down into the teens up at Guitar Lake in August. Elevationplays a key role of course. If you find youself getting cold replan your camps to be at lower elevations. Each 1,000 feet of loss can gain you an average of 4 degrees.”

“As a bona-fide gear whore I have a bunch of sleepy bags & other stuff.. and even though I'm always trying to watch my pack weight I never take anything less than my 20 degree bag, my 100wt fleece tops & bottoms & my fleece cap to sleep in, whenever I'm headed to higher elevations in the Sierra. Too easy to get "surprised" by temps & weather you never would have expected!

There's no such thing as "predictable" weather up there! Love the Boy Scout Motto - "Be Prepared"!”

“Thanks one and all. You have convinced me that it's better to be a pound and a half heavy at 35 degrees than to be a pound and a half light at 15 above. Good advice and I will hope to see some of you yahoos on the trail.”

“Are you hiking solo?”

“It was that hail storm in '99 and that snow in 2000 that convinced me you had better be prepared when you are up high. If you are hiking through fast and light then you will probably be walking during the storms but if you plan on relaxing a day and leaving the tent up while you go out and fish or explore, better have a tent that you can button up tight. Otherwise you might come back to camp and find everything wet. Not a fun prospect considering how cold it can get after a storm.”

“I don't plan to be solo unless my buddy goes out early. I own a Big Agnes waterproof 15 degree bag that weighs about three pounds (Deep Creek). I plan to tarp-tent with a 10x8 silnylon tarp which I make an a-frame. Honestly I expect my pack will weigh about 30-35 pounds with food, and I'm taking my time. No rush. I intend to fish a lot and enjoy the camping as well as the hiking.”

“Sourdough: At that pack weight and as long as you expect to be out between resupplies( you haven't mentioned that) I'd expect you REALLY like to eat fish.”

“Good point, landscasperjb. Yes I do like to eat fish and I hate to admit it but my buddy and I do intend to sacrafice a few of those little beauties to the god of hunger as need be. However in the first 100 miles we wont need to carry more than five days of food due to resupply at Toulumne Meadows, Red's Meadow and Lake Edison. That will be less than 10 pounds at each start and we're traveling pretty Spartan otherwise. From Muir Trail Ranch on I see a heavier pack with maybe no more resupply.”