Competition. Tioga Pass Prognosticator No:27. Spring opening.

[Southwest Dave]

This week saw the Yosemite and Mono county crews meet as they have plowed the entire pass to at least one lane wide. There remains a high risk avalanche risk at Olmstead point that needs monitoring and there is still a lot of debris to clear as well as preparing the side roads and utility areas. A lot to do still but a step in the right direction.

Dave.

[tseeb]

Since both Ebbetts and Sonora Passes opened on 5/30, I compared when they opened vs. Tioga since winter of 2011/11.

For the two most recent winters with high snowfall (2010/11 and 2016/17), Ebbetts and Sonora opened 11 and 22 days before Tioga in 2011 and -1 and 16 days before Tioga in 2017. That gives an average of 12 days which would put Tioga opening at 6/11/2019, exactly between two guesses during that week. If I throw out the -1 (when Tioga opened a day before Ebbetts), that gives an average of 16 and puts the opening at 6/15/2019, a day after my guess made almost two months before.

If I average all 8 years of data from 2011/12 to 2017/18, I show Tioga opened almost 9 1/2 days after Ebbetts and almost 13 1/2 days after Sonora. Still not very helpful since Ebbetts and Sonora opened the same day this year.

If anyone wonders why 8730' elevation Ebbetts opens on average 4 days later than 9620' Sonora, I think it's because Sonora is very steep at the top on both sides so there is not as much road at high elevation. Highway 4 is about 7000' at Lake Alpine, where it closed for winter and goes up to 8730' at Ebbetts. It then drops to 7600' at Pacific Valley before climbing to over 8000' at Pacific Grade Summit. It is also possible the average could be thrown off by the two times Ebbetts in the last 8 years that it opened after Tioga or that Ebbetts is the least heavily used of the Sierra passes so there is not as much effort on it as Sonora. More info at https://en.wikipedia.org/wiki/Ebbetts_Pass and https://scenic4.org/the-route/points-of-interest/

[Mark Sedenquist]

@tseeb, it is entirely possible that your statistical analysis will give you an inside edge on this year's contest -- but there's nothing like blind luck. (Please see my winning entry for closing last year).

And, the fact that the Sierra's got an incredible amount of snow this year. I actually think the most likely opening this year will be July 2nd at 4 pm.

Mark

[Southwest Dave]

As my first prediction passes by I am going to throw another dart myself and predict that the pass will open on June 22nd at 8am.

Dave.

[glc]

Ebbetts opened late in 2017 because there was severe road damage under all the snow that had to be repaired.

[CAnative]

NPS website for Yosemite says that road work will Start on Big Oak Flat road on June 10th and then on Tioga Pass road after it opens. Work will be done on weekdays and expected delays of 15 mins. So it appears they won't hold off on opening road until all of the work is completed on it.

[Mark Sedenquist]

So it appears they won't hold off on opening road until all of the work is completed on it.

That would appear to throw a possible monkey-wrench into our terms of engagement as to what constitutes the road opening.

But that's why Sheriff Dave is paid THE BIG BUCKS to make decisions.

Mark

[Southwest Dave]

Nothing has changed really. Perhaps they are referring to routine maintenance the same as other roads in the park that need repair after a winter season. Once the road is open to traffic and it's been officially announced we have the date, roadworks or not. It would seem they may keep us in the dark from now to the point of opening though.

From Yosemite website.

Crews are working on side roads and utility areas. Much additional work remains prior to opening. As this work is routine, there may be no further updates until the road is ready to open. There is no estimated date for opening.

Dave.

[tseeb]

While I think it will open earlier, the earliest I can select today is July 1 at 8:30 AM so that is my new guess.

[Southwest Dave]

Yosemite have said it will not open this weekend but that does not imply it will open soon after. Work continuing around Olmstead point in particular which suggest an avalanche risk remains. Watch this space.