Yosemite Valley Depth Guide

I’m going to Yosemite Valley tomorrow and will take my kayak. The website says that you can paddle the river as long as:

The depth is 6.5 feet

The Sum of Air temp, and Water Temp must be below 100.

This does not make sense. Like in the Summer, the air temp is 75, the water probably 50…that adds up to 125…more than 100, but you can paddle then.

I’m guessing the air temp right now is about 65 degress, and the water about 42. That adds up to 107. That is over 100, so it makes sense, but not in the Summer.

Anybody shed light for me?


Sounds like a typo

– Last Updated: Apr-12-07 12:44 PM EST –

A commonly quoted safety rule is to not paddle without immersion gear (wet suit or dry suit) if the temperature of the air and water add up to LESS than 100 degrees F. It's not a fool-proof rule, but it's not too bad. That is probably the recommendation they were trying to make. If that isn't the answer, then I have no clue.

Oh yeah, and that "depth" figure is probably a gauge reading. It may be that the river is considered unsafe at a gauge reading greater than 6.5 feet (water too fast and high), or not runable below that level (too shallow). From what you say, it I can't be sure. Gauge readings are arbitrary, and have no relationship to actual river depth. Usually it's nothing more than a "giant ruler" nailed to the side of a bridge pier, and if it's something more modern, the scale that is used got it's start in some similar arbitrary way.

Yes, You Are Correct
Yes, this is why he said it is still too cold. What you say makes complete sense now. I understand what it means to have the combined temps be less than 100 degrees Farenheit.

And yes, the water level may be higher than 6.5 feet, making it somewhat unsafe for the average paddler, rafter, or person on an innertube.

Thanks for clarifying this for me. I appreciate that.

Night Time Air Temps Below Freezing
Night time air temps in Yosemite Valley are still well below freezing. They had snow this week. Remember the water in the Merced River is about 100% snow melt.

Its hard to imagine how cold it is in Yosemite Valley when you are 75 miles away in the San Joaquin Valley and its nearly 80 degrees.

This time of year tourists, including Californians, are showing up with nothing but shorts and T-shirts and going home early, or buying some really expensive clothes from the tourist shops…