High Sierra Topix

longri wrote:

SSSdave wrote:I'd bet few here actually have a thermometer in their backpacking gear and that inputs are likely mere guessing unless a person specifies how whatever was measured and where.

Of course. Most people have no need for the information. Even if you have one, how do you know it's accurate? Who calibrates their thermometer?

For the purpose of the thread a few degrees inaccuracy won't matter for the sake of an informal web discussion like this. However without a thermometer I won't trust what someone thinks cold temperatures might be simply by how such feels to them. Personally as a hardware electronics career person have a dozen or so themometers including some on my multimeters as attached probes calibrated to voltage reading scales that I could easily compare for ballpark confidence if that mattered. Since mid 80s installed digital themometers on the outside of my Suburus, well before that became a feature of some vehicles, as have always been interested in how temperatures change going through different landscapes. Also as a snow skier, extremely useful on snowy mountain roads for understanding when slushy road surfaces are more likely to be dangerous.

Despite many a snow camping trip at high elevations (though mostly in the spring), the coldest I have recorded was 7 degrees at Lower Lola Montez Lake near Donner Summit, in November. Honest to gosh liqiud thermometer. 1976. I have been on plenty of trips where I expected to have it get colder than that but it never has. Temperature is strange sometimes. Went on one spring ski trip, march I believe, Desolation, which my buddy and I always referred to afterward as "the 40 degree trip". Every time we looked at the thermometer for three days straight, no matter what time of day or night, it read 40 degrees. And no, not a malfunctioning digital job, a liquid unit that I have used many times before and since. Actually a rather damp and dismal trip for the most part, did not see the sun for those three days and it was humid, so a damp cold in which nothing would dry.
Other end of the spectrum was 1993, late summer on the JMT, so warm we never broke out even a windbreaker during the day, even on the high passes, only wore more than a t-shirt early morning and late evening. Canyon of the San Joaquin was brutally hot.

If you look at various Sierra locations on the NWS website for the current cold snap, you seel that the valleys are actually colder than the higher areas. You can get 10+ degrees colder simply by selecting a campsite in the wrong location! Years ago in winter, I was camped at Camp4 in Yosemite Valley, cold as hell! All bundled up I started up the Yosemite Falls trail only to become so over-heated that I had to fashion a "tank top" out of two handkerchiefs, LOL. Camp on the top of the rim of Yosemite Valley in winter and you will be warmer than in the Valley.

By the way, you can tell it is cold, without a thermometer, if you lick metal and your tounge sticks, or when you get frost on the inside hairs of your nose.

Coldest when I had a thermometer along to verify was either -8 or -12, too long ago to remember for sure. It was between 30 to 35 years ago up on Tioga Pass in mid December. The friend I was with had never been out overnight in the snow before, or on skis either for that matter, but did have lots of Sierra experience with a pack on. We had pitched a tent between 2 cabins at TPR, and made it through the night. The coldest temps were actually the next morning, after sunrise when it grew colder the later it got. It was all we could do to keep our heads and hands out of our sleeping bags while playing cards when my friend just snapped and jumped up and started throwing everything of his in his pack. He couldn't handle the cold any longer and said that seeing how he drove us up to the trailhead, if I wanted a ride home I had better get my ass up and get packed because he was leaving. Not sure of the miles between Lee Vining and Pasadena, but I am sure it was further than I wanted to walk or hitch hike. To this day I can get him to go backpacking anytime spring, summer, or fall, but trying to talk him into a hike when snow is on the ground is a ****.

One time overnight hiking down a closed road in winter in the local mountains (San Gabriels in SoCal) we spent the night on an exposed section of asphalt pavement when everywhere else had snow a couple feet deep. Think it being bare of snow was due to it being on a curve and the wind blew the road bare. The next morning when I got up to take a pee, it froze instantly upon hitting the asphalt. My question is, how cold do you think it would have to be for liquid coming out of your body at 98.6 degrees to freeze that fast? Wish I had had a thermometer that time.

On a late season fire (December) the measured low was -18 with a 20mph wind blowing. Not much fire got put out that night...

The coldest air is in the canyon bottom and ridge top. The middle third of a slope is called the thermal zone and can be 10F+ warmer than the V canyon bottom.

Wandering Daisy wrote: By the way, you can tell it is cold, without a thermometer, if you lick metal and your tounge sticks, or when you get frost on the inside hairs of your nose.

I don't know about licking metal (visions Ralphie in of "A Christmas Story" come to mind) but your nose hair freezes around 0 degrees F.

The coldest I've experienced in the Sierra was 10F. The thermometer on my watch only works to 14F, but I remember Alpine Mike saying, "It's TEN!" in the morning. . . but I was wearing shorts with snowshoes on the way out that day:)

This is a pertinent topic for our family, as we now spend most of our Sierra time in winter and spring. I experienced my coldest straight temperature on my last ski trip: -14 on Feb. 20/18 (note that on that night I was in the TM ski hut, feeding the woodstove). Two days later, the temp was -9. On this trip the coldest night I spend out was just 0, with blowing snow bringing the wind chill down below zero... perhaps -7. (temps. come via the winter ranger's met station, so pretty accurate.) Skiing in one Jan. down "Cold Canyon" to the Toulumne River, I slept right by the frozen river on a dead still night that was -6 or so. I slept warm without anything but my ancient -30 down bag and a ridge rest.

The coldest recent temps that I know of from the Toulumne was the -22 they recorded in mid Jan. 2013, but I bet there were colder nights. We too would like to know the very coldest ever recorded in the Sierra; Bridgeport has a very cold, 40 below zero reputation. Where are the best historic records kept?

Harlen wrote:Where are the best historic records kept?

The best source I know of is CDEC but their temperature record for Tuolumne Meadows only goes back to September 1999.

It seems likely there were colder nights in Tuolumne in the last 50 years and pretty much guaranteed it was colder during the last glacial period 12,000+ yrs ago.