Messenger Clouds foretell the "Hurt"

As an avid outdoorist, have you ever wondered how some people just seem to be better prepared when the weather suddenly changes? Consider the following scenario:

It’s early Fall, not August-warm, but balmy enough to entice you and your friends out for a float trip. The forecast for the next few days looks pretty good, so you grab permits, friends and 4-weights, and go off for a 5-day river adventure.

On day 3, you’re camped at the confluence of a beautiful side canyon. There was a bit of a halo around the moon last night and early morning you’re musing on this, and some streaky, turned-up mare’s tails as you sip at your first cup of joe. You make a mental note to occasionally glance skyward across the morning. If changes keep brewing, the next 24 hours could be interesting.


Halo cause by ice crystals is cirrus or cirrostratus

Morning Cirrotratus

Late morning, floating downriver to the next camp, you notice those mare’s tails invading from the NNW are now pronounced, thickening, and covering much more of the sky. The pattern suggests a cold front. It should come and go quickly, but what will it bring with it? Regardless, it will mean a tent and a fly tonight, well staked down to survive the inevitable gusts and blusters. And as a precaution you’ll make sure that the kitchen is put away, the camp made gust proof, and the boats are well tied (alpine butterflies anyone? ). A bummer you won’t be able to sleep under the stars tonight, but hey, it’s likely the fishing will be good at the lunch break!

Mares Tales are cirrus uncinus

The fish were active at lunch and now on your recommendation, everyone has eaten early, and storm-proofed the camp. It’s time to set the chairs out and watch the show in the sky as cumulus continues to surge up and darken overhead (happening fast!). They’re getting taller, darker, angrier, and you can see and hear the internal flashes of lightning as cumulus turns cumulonimbus. The temperature is dropping, 20 degrees plus, with very stiff, gusty winds. Now the hail starts. It’s a full-on thunderstorm. Time to retreat to the tents.




The thunderstorm is a beauty. By the time the front has passed 3 hours later there is an inch of hail on the ground. There was not as much rain as you were expecting and the breaking cloud suggests morning will start out clear and fall-like, air crisp and dry, 50 degrees instead of yesterday’s balmy warmth. Everyone is happy that no boat was blown free, and nobody’s tent needs to be retrieved from 100 feet up a canyon wall.



At the takeout, it’s time to reflect on a memorable trip, one that will always be remembered for purple clouds ripped open by bolts of horizontal lightning and sheets of pelting hail. A stupendous show instead of last-minute scrambles to secure the camp and boats.

I’ve lived versions of this story in the mountains in summer in New Zealand, Montana and Colorado; canyons in the west in the Fall; and in the high desert in the spring. And with this story hopefully is an answer to the question “why look at clouds?” Besides the stunning beauty (check out https://onda.org/2020/01/appreciating-stormy-skies/), every outdoor adventurer I know has had to beat a retreat, batten down or cut an adventure short ahead of an unexpected changes in the weather. And even though most active outdoorists are pretty good at reading their surroundings, and are handy naturalists, I’m surprised how often I’m asked “how did you know the wind was going to do that?” or “how did you know we were going to get that storm?”

Outdoorists have always had to keep a weather eye, not just to pick the best of moments for adventures, but to roll with changes when they hit. Spend enough time in the outdoors and you will get snowed on in August, hit by an unexpected storm or squall, or wander into something outside the expected forecast.

The reason for this post is simply to make the case that basic comfort with weather requires an expertise no more difficult than say, a comfort with animal tracks. And just as I don’t always get it right with tracks in the ground, I don’t always get it right with the weather. But tracks in the sky are just like tracks on the ground - you don’t need to be an expert to have fun and get a lot of information out of the signs. You’ve just got to remember to look (up)! A second here, a second there across your day, nothing more is required!

More sketches:

Cirrus (Ci), Cirrocumulus (Cc), and Cirrostratus (Cs) are high level clouds. ...

Altocumulus (Ac), Altostratus (As), and Nimbostratus (Ns) are mid-level clouds

Cumulus (Cu), Stratocumulus (Sc), Stratus (St), and Cumulonimbus (Cb) are low clouds.]

Special thanks to my mountaineering, flying and sailing friends who first got me interested in all things squally and stormy…

Sources, and more:

Natural history of the Pacific Northwest mountains: plants, animals, fungi, geology, climate. Daniel Mathews. Timber Press Inc., 2017.

https://www.weather.gov/jetstream/cloudchart, Don’t miss clicking on the individual clouds in the cloud chart for more information!

For some gorgeous clouds-over-the-high-desert, check out https://onda.org/2018/09/appreciate-clouds/