View Full Version : lightning safety in san juans and the tree line
As someone who hasn't spent much time in Colorado in the summer, the lightning danger advisories seem a bit mysterious.
I'm planning a CT hike this August and was just poring over the TI maps of the San Juan mtns and was wondering if getting below treeline is safe enough during those famous afternoon storms. And is there no way to be safe above treeline?
For example, I was looking at the CT trail between San Luis Peak and Snow Mesa and it seems almost entirely above treeline but there are a few points where one can quickly get below treeline by leaving the trail. Is this what the experienced ones here would advice? Or can you find sheltered locations (like a low lying area between higher places..) above treeline?
Sorry for the vague question but it's hard to know what to expect when you are from flatland.
My method of finding shelter in above-treeline storms is to pitch my tarp and wait it out sitting on my dry sleeping pad. Nothing will protect you from a direct strike, but that's extremely unlikely. The greater danger is from ground currents from nearby strikes, where the voltages across the length of the body are in the hundreds of volts, not tens of thousands from a direct strike. It's best to have as small a contact area with the ground as possible, so if you can sit or even crouch on your pad, that's ideal. This is not the best shelter and I only do this if getting below treeline is not feasible.
It's easy enough to estimate if a given storm cell will intersect your path. You can estimate its distance with the 5 seconds = 1 mile formula for time of lightning flash to thunderclap. You will be able to estimate its direction of travel from the wind you'll be feeling and from watching the storm (almost always westerly winds, clouds heading east). So you should have quite a bit of warning to get as low as you can and pitch your shelter. You don't necessarily need to seek shelter every time you hear thunder--the storm may be 5 or more miles away and moving in a different direction.
There were times on the CT when I could literally outrun a storm cell and leave it behind me, and other times when a storm developed so fast right above me I had little time to do anything but an emergency pitch in high rocky ground.
I think Garlic's advice is pretty good. In addition to that, I would add that lightening is seldom an issue before 12 or 1 pm -- so it's best to start early when you're going to be exposed so you can get in ~6-7 hours without worry. It's much safer to be surrounded by trees than to be a high point yourself -- just take care that you're not right next to a tall tree.
Even on Snow Mesa there's variation in the terrain... if lightening is threatening, shelter low but not by a stream or overhang.
That section you are asking about is pretty much of a plateau.
Would be one of the tougher ones to go dowhill from.
I agree with Garlic and don't even worry if i have more than 5 seconds.
I'm even ok with 3.
You need to be lower than the highest point obviously. But not in a ravine or gully (lightning likes these kinds of places)
Normally, lightning in CO is in the afternoon from 3 PM onwards. (normal but not always)
so, I'd check out the section on Google Earth (Use shift key and mouse wheel to tilt the earth and exaggerate the terrain to study the section in question and try to hit that 10 miles or so in the morning.
Have fun. (I've had a few close calls but mainly because my safety time was always a bit less than others i hiked with.)
Never had a problem with lightning while backpacking...
One time though, I did trail work and we saw the lightning strike a ridge less than a mile away do in the Spanish Peaks. (http://en.wikipedia.org/wiki/Spanish_Peaks)
Nothing like being near lightning strikes while being surrounded by piles of metal tools. :eek:
I am afraid my experience through this section was harrowing, to say the least, due to lightning.
First, we camped on Snow Mesa near the pond on a day with no lightning but strong squalls. Unfortunately after dark the lightning started. It made for a very unsettling night, should we stay put or pack and hike on in the dark? We definitely felt like lightning targets.
The next day on Jarosa Mesa, the sun was shining but a storm built above us. The first strike knocked one of our group to the ground. (He was not injured) We tried to shelter but the only available cover was shorter than our sitting height. Three or four strikes within about a quarter of a mile of us. Again very harrowing.
With frayed nerves we went off trail down lower to trees to make an early camp. That night there was a very intense very extended lightning storm which I really believe would have been life threatening had we been camped on the Mesa. (We were fine where we were).
That said, there were definitely places to shelter if one had half an hour to an hour of warning that a storm was approaching. In our case it was the first strike of the day that was the really close one and the nighttime storm that was the harrowing one.
The first thing on the Colorado Trail that would scare me seriously is lightning. The weather pattern remains pretty much the same at the time of year when I thru hiked in San Juan Mtn. range last month.
Despite one crazy thunder storm mixed with lightning, hails, and heavy down pour near Antenna Summit, in which I stopped early and pitched my tent on a slope, and stayed overnight with a highly decomposed sheep 50 yards away, the positive side of the experience is what I got from a sheep herder, David, on Snow Meas. He said he would always ride on the horse and never seek for a shelter or a low spot on the mesa. He'd never got hit by any lightnings during his months long assignment. I'm kinda lighted up and felt more confident in the rest of my trip when got hit by a nasty gale storm at Verde Lake above 12,200', and rain/lightning in the morning from Animas River to Molas Pass.
I personally feel one should always take prudent approach. When a storm comes, one should either retreat to the tree line (may stay under trees, but not too close to it), or pitch a tent at a low spot/in brushes/behind rock out crops in a exposed area if can't get down to the tree lines quickly. Sometimes, a "storm" could be like a monsoon, last for hours. Colorado weather is unique.
Last year a ranger told me that they lost a shepherd to lightning near Stony pass.
People have been struck by lightning at 10 miles from a storm. It's random as he!!.