Snow and Water levels 2011

[Cross Country]

When my school district had us start before Labor Day it cut out one trip per year from then on. Booo.

[rlown]

richlong8 gives a really good list. I have two more to add. One which is common is known as ice bridging, where you get snow, then rain, then cold....then whatever....but in a nutshell the symptom is layers of ice with air pockets underneath resulting in inaccurate depth readings. Another thing which I believe can affect some of the sensors located on or nearby slopes is lateral movement during melt resulting in rapid changes in reported data.

I thought they tried to put the sensors in a field rather than on a slope? I can see how the sensors get confused on the thaw/freeze thing. My only reference was seeing the snow field up around summit lake near piute pass. That seems to be a "manual" sensor though.

[exodus]

When my school district had us start before Labor Day it cut out one trip per year from then on. Booo.

That bites for sure. I go on a yearly trip with someone in the same situation. Because of a number of different factors (including starting school so early), we really only have one week we can go together now because my kids have to be out of school, we can't trounce on other vacation plans, and he starts in the first week of Aug! It's just getting going up there at that time in some years.

[exodus]

Oh, to stay on topic here... this thread is AWESOME. I thought I was the only one who obsessed over snow depth and water content. I literally watch snow melt from about mid-March to June (for the aforementioned reasons above0.

I agree with a lot of the assessments here in that it really matters how warm the Spring is. Even these small storms we have in the Spring don't seem to have a huge impact at a high level on when things open up because the snow from them quickly melts. However, for those of us planning early season trips, they can make a huge difference... just a few days can mean an entire lake basin ice free or not.

[ERIC]

I thought they tried to put the sensors in a field rather than on a slope? I can see how the sensors get confused on the thaw/freeze thing. My only reference was seeing the snow field up around summit lake near piute pass. That seems to be a "manual" sensor though.

Yep, they typically do. But during melt even a slight slope under or surrounding a sensor can have an affect (even if the slope is 100 or more feet away from the site). A few of the higher elevation sensors are either located where the clearings are small surrounded by sudden drops or inclines (e.g. on or near a pass), or, are on a wide-ish clearing with a gradual slope.

[kpeter]

The CDEC servers are temporarily down, but the 5/16 summary report is available for all stations.

During the 7 days through 5/16 the following 9500+ stations lost water content:
Dana Meadows, Mitchell Meadow, Crabtree Meadow, South Lake.

....and the following 9500+ stations added water content:

Blackcap Basin, Upper Tyndall, Leavitt Lake (I cheated on its elevation since it is a popular station!), Cow Pass.

The amount of water content added does not look huge yet--perhaps because last week involved some melting before the snows arrived--so the full impact of the snow does not register in a weekly report. But it is interesting that about half the stations lost water content despite the snows through Monday. The snowfall must have been somewhat erratic.

But as I said, who cares about the snow? In a season like 2006 about 15% of the water content melted each week in May, and in an average year perhaps 10% a week in May and more in June. We have seen 0-5% melt a week so far.

sigh

[Mike M.]

An ominous note: the wording on the Yosemite website was changed late last week in reference to the Tioga Pass reopening. It now reads: "The Tioga Road (Hwy 120 through the park) is closed, probably until mid to late June (due to snow)."

Mike

[kpeter]

The Tioga message is a bit ominous.

I've been monitoring the Kibbie Ridge station since I'm thinking of an early season trip to NW Yosemite. Last year I went to Vernon Lake on June 16, and it was perfect timing.

This year the Kibbie Ridge station is exactly 8 days behind last year's schedule. Since it is at a relatively low elevation it could still catch up quite a bit if it warms up. It was dry last year by June 1. It currently has 15" of water content--the same as it had on May 15 last year (today being May 23.)

At the moment it looks like even lower elevations are one week behind last year, which itself was about a week later than average.

[Cross Country]

Just remember this: on a really high snow year there a few places one can go. Those places are usually crawling with people. Part of the reason I went BP instead of camping was to avoid overcrowding.

[Mike M.]

Tioga Pass opening update, as of 5/23, from the park website:

Last Update: May 23, 2011

Tioga Road: Yesterday, crews plowed from May Lake to May Lake Pit. Snow depth is 15 feet or deeper.

Additionally, as of May 20, Mono County Public Works and Mammoth Mountain crews have plowed to 3.8 miles from Tioga Pass. Mammoth Mountain is using snowcats to expedite the process.

http://www.nps.gov/yose/planyourvisit/tioga.htm" onclick="window.open(this.href);return false;

Excellent progress. Fingers are crossed. 15 feet of snow is quite a bit. Plus, the days have been mild to cool in between storms -- we need some hot weather to help things along.

Mike