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Tioga Road opening date prediction...

PostPosted: Sat Apr 29, 2017 9:12 am
by Justin-T
I think many people are naturally interested in this question, especially this year with the massive snowpack, officially 143% as of April 1. I decided to use the data going back to 1980, showing snowpack on April 1 each year with the actual date the road opened, to get a prediction. The data is available here:

https://www.nps.gov/yose/planyourvisit/tiogaopen.htm

A regression shows there is - no surprise here - a strong correlation between the amount of snow on April 1 and the opening date (r2 = 0.75) and the regression line allows me to predict an opening date of June 14 for 2017. You can see though that there is a lot of variation, with very similar snowpacks producing dates from May 24 (137%), to July 1 (156%). Here's the data (not sure why Excel converted the real dates to a 5-digit number :roll:, so I marked a couple of points that bracket the intercept at 143%):

Image

Re: Tioga Road opening date prediction...

PostPosted: Sat Apr 29, 2017 9:22 am
by AlmostThere
Unless of course we get more snow. Another system will be coming through late next week.

Re: Tioga Road opening date prediction...

PostPosted: Sat Apr 29, 2017 9:33 am
by Justin-T
True, but I bet there was snow in May in some other years too... Anybody want to make their own prediction? :twisted:

Re: Tioga Road opening date prediction...

PostPosted: Sat Apr 29, 2017 11:14 am
by MadDiver
Cool, nice work!

Re: Tioga Road opening date prediction...

PostPosted: Sun Apr 30, 2017 7:18 am
by balzaccom
And Yosemite just announced that the Bridal veil Campground is open for reservations starting August 1!

Re: Tioga Road opening date prediction...

PostPosted: Sun Apr 30, 2017 5:28 pm
by Phil
Can we take random guesses, or do we have to be scientifical about it?

So, aside from rockfalls, downed trees, sidings, etc., if we take out what they're doing from the east, we have about 45 miles to the east gate at Tioga Pass. As of the 27th, and assuming that they began on 04/15, they had plowed 14 miles from Crane Flat. Barring more snow and big problems, say maybe just slightly over a mile per day, then maybe throw in 10 days for touch up and problem areas.

Even logistically, without historical averages (although there is a correlation), you're probably about right. For the sake of argument though, I'll go ahead and say 06/19. But really, from my perspective, it opens on whatever day I get there. Then the only problem left is being able to walk more than 100 feet off the shoulder without being at least up to your knees.

Re: Tioga Road opening date prediction...

PostPosted: Sun Apr 30, 2017 6:14 pm
by Justin-T
Phil wrote:Can we take random guesses, or do we have to be scientifical about it?

Just a bit of fun, so you can pin a calendar up and throw a dart at it if you want. If the page you're aiming at is June I have a feeling you've got as good a chance at being right as me. 8)

Re: Tioga Road opening date prediction...

PostPosted: Thu May 04, 2017 11:58 am
by Phil
Slow going for the plows. As of the 3rd, they're only to White Wolf. Wet snow and only making 1/2 mile per day of progress.


https://www.nps.gov/yose/planyourvisit/tioga.htm

Re: Tioga Road opening date prediction...

PostPosted: Thu May 04, 2017 8:12 pm
by Justin-T
Do they clear only west to east? No crew coming in from the Lee Vining side? Must be at least 25 more miles to clear from White Wolf!

Re: Tioga Road opening date prediction...

PostPosted: Thu May 04, 2017 8:51 pm
by Phil
I may be wrong, but I think that the Caltrans crews only plow from Lee Vining up to the gate at the Tioga Pass entrance station. And I believe that the NPS crews only work west to east with the park boundaries because of access problems from the east where they would have problems bringing in equipment because it's not stored there.They have a lot of avalanche zones, and the site said they were doing advance work at Olmstead Pt, so I'm sure they're throwing a lot of anfo satchels this year, because I doubt they're using Avalaunchers or artillery pieces.

Re: Tioga Road opening date prediction...

PostPosted: Thu May 04, 2017 8:53 pm
by AlmostThere
Still thinking mid to late June. Unless it's unseasonably hot up there for extended periods. It was freakin' hot in Fresno today, 98F and yet, it's dropping like a rock over the weekend to the 70s again, they say....

Re: Tioga Road opening date prediction...

PostPosted: Thu May 04, 2017 8:57 pm
by Phil
Yesterday at this time the AC was running, tonight it's the heat. Although we did have our first rattlesnake of the year about 2 hours ago.

Re: Tioga Road opening date prediction...

PostPosted: Fri May 05, 2017 10:23 am
by Bighead
Things can change but May is supposed to be well above average temps. Also as everyone knows "wet snow" actually melts faster and your snow pack is significantly wetter this year. I'll guess June 9th.

Re: Tioga Road opening date prediction...

PostPosted: Fri May 05, 2017 10:41 am
by AlmostThere
Only because they are plowing, not because the melt will be done.

It's snowing this weekend on the pass, in the high country. 25 F predicted for Saturday night at 9000 feet.

Re: Tioga Road opening date prediction...

PostPosted: Thu May 11, 2017 10:03 am
by Justin-T
Looks like they went about 5 miles in 6 days (White Wolf on the 3rd, to near Yosemite Creek by May 9), so still a long way to go, but they seem to be speeding up a bit, he says hopefully. :D