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Home :: Recreation :: Mountain Safety Info :: There's Weather Out There
There's Weather Out There

by John Devitt

One of the great joys of hiking in the mountains is to be able to do it in glorious sunshine and clear air, and it seems to become more glorious and even more clear as we get higher and higher on the trail.

At any time of the year, however, this scene can turn into a cold and wet one in much less than an hour. Colorado, in particular, is located astride the Continental Divide, and our high mean altitude and usually dry climate combines to produce particularly rapid temperature changes. Plans can change in a big hurry.

So what do we do about this and what should we try to learn to make our climbing more fun as well as safe? We can begin by thinking about the year's weather patterns. As spring begins to turn into summer we can begin to believe that a sudden temperature drop will not cause a major safety problem. We may get uncomfortable but we are less likely to stumble into a life-threatening situation. As the real summer is upon us our major concern will be thunderstorms and lightning. We will discuss the latter below. But we also must keep in mind that snow, sleet, and strong winds can make us very uncomfortable in any month of the year, particularly at higher altitudes.

Problems become more serious as autumn approaches. September is, to many of us, one of the very best climbing months., but it is also more unpredictable. Many have experienced a major snowstorm up high in early September. (Would you believe late August? Early August? Late July, etc!!!) However in the fall of the year, the average temperature is lower and sudden attacks of wind and precipitation can become a major threat to those who venture out in only light summer garb. Deaths by hypothermia have occurred in this way. So when autumn has truly arrived, the full complement of winter precautions should click into place and stay in use until the late spring, where this particular story began.

Even in Colorado, weather forecasting has come a long way. The late-night TV forecast is a great help in planning for the next day or so. It's probably completely useless beyond that time, except for the satellite cloud patterns, cold fronts, and high and low barometer symbols. This broader area information changes more slowly and is at least a hint of what the future holds.

Some weather patterns seem to be peculiar to certain mountain areas in Colorado. There are periods in the summer when areas of the San Juans seem to be rain-forest country. In the two-week 1982 CMC Outing, there was only one day when the morning's plans remained intact the rest of the day! In the rest of the state, it is always a good idea to start as early as practical. You just might miss the afternoon rain.

One of the most useful tricks is to stop occasionally, long enough to watch the cloud motions. Notice direction and speed, as well as the colors of the clouds. We all know the dark ones can mean a storm, but the light ones can turn dark very quickly. In the winter, the cloud masses are often so large they cover the sky; therefore you will need to look more for wind and temperature changes.

Summertime lightning storms are an especially puzzling problem to many hikers and climbers. Here again, stop long enough to enable a judgment of the direction and speed of storm cloud movement. If you are on a ridge or summit and the cloud is coming toward you, descend if possible. Descending a few hundred feet down a steep slope will probably get you out of the danger zone. If in doubt, keep descending. Often, the problem will pass and then progress can be resumed. Stay away from water in any form. Spread the party out so that if the worst happens, the rest of you can be useful in helping the victim.

Many weather precautions are "mountaineering common sense." Take good equipment and clothing, watch for weather problems before you are in the middle of them, and have a good time!

Lightning!!!

Places to be during an electrical storm, ABOVE timberline--

  • Several hundred feet below ridge top or summit.
  • Away from water -- snow, wet gully, lake or pond.
  • On your feet, possibly crouching, hands not touching.
  • In the shadow of a cliff if possible -- even notch in a ridge.

Places to be during an electrical storm, BELOW timberline--

  • In trees is OK, but not standing by a tree, especially a tall tree. Stay on the trail.
  • Away from stream or lake.

If temporarily out of the timber, the above items may apply.

Other hints:

  • Set your ice axe down, away from you. The same goes for metal-frame packs. (Is your internal frame made of metal?)
  • If in doubt, descend.

Avoiding Lightning Danger

I often encounter hikers and leaders who have misconceptions about lightning. Someone who is unreasonably afraid of this hazard can be as big a problem to the enjoyment of a trip as the foolhardy party member.

Summarizing here are the main points important to a hiker or climber:

  1. Lightning is a serious hazard when: a hiker...
    • acts as a "lightning rod," as in standing on a ridge above timberline.
    • acts as a preferred electrical conductor of lightning ground current, as in leaning against a wet rock wall with hand or shoulder while standing in a wet gully.
    • is zapped by induced current, as in being near a tall tree, which is struck by lightning.
  2. If you have descended from the treeless ridge crest at least 100 feet down a steep slope, you are probably quite safe if you continue to stand. If instead you lie down, feet pointing down the mountain, ground current could enter your head and leave through your feet. This is probably very bad news! If the slope down from the ridge is very gentle and treeless you are in a place similar to an open meadow and you are still the lightning rod. Keep descending until you get to either a steep slope or the trees.
  3. Hiding in a cave or depression could put you directly in the path of the ground current. Better to be above the current on a rock, on feet only or kneeling - but not with hands on the rock also!
  4. Avoid, if you can, any area wetter than its surroundings. The boulders are safer than the snow or wet gully. Worst of all is a lake or stream.
  5. If you are carrying an ice axe, or similar gadget, it is dangerous primarily when you are close to the electrical activity. If the axe is in a lightning-rod position, it could carry current from your hand to ground. Get rid of it temporarily. Carrying it horizontally in a headlong retreat is probably okay.
  6. If the worst happens and your party finds itself uncomfortably close to the electrical action, spread out as you descend. Then, if someone is injured the others are still available to help. CPR may have to be started immediately. There may also be burn injuries, but by comparison they can wait.

These hints apply to your basic hike or walking climb. Complications arise on technical routes, although the principles still apply.

From Trail and Timberline , No. 915, March 1996. ©1996 Used here with permission of the author.

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