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Winter Pre-Trip Planning


Pre-Trip Planning and Preparedness for Winter Trips

by Andy Dappen

Winter outdoor adventures demand more thinking than many summer activities. In winter you need to be tuned into snow, weather, and terrain to know the avalanche hazard. Meanwhile,  minor emergencies can magnify in seriousness  so you need to consider both big and small details. Finally, in winter trails disappear under the snow, so finding your way around requires more planning and skill. Enjoy the mental gymnastics of all this -- it’s fun preparing for and traveling through winter.

Many believe that great field skills and knowledge are the tools for contending with all of the above but pre-trip planning is the main ingredient behind winter preparedness. Knowing the expected weather for the region and elevations you’ll be visiting helps you pack appropriate clothing/gear and anticipate how the snow pack might change (which affects snow stability) while spending the day out. Knowing the regional avalanche forecast for the day ahead will help you pick a destination and terrain that’s safe. Consulting guidebooks (e.g., WenOut snowshoeing guidebook) with the descriptions of many possible destinations will help you find an outing that’s appropriate given the day’s avalanche hazard and will also tell you whether there is special equipment (avalanche gear, ice axes, crampons) you should be carrying. Studying topographic maps from the USGS (on a computer see National Geographic Topo! CD maps or see the Gmap4 system), slope steepness maps from Caltopo.com, and satellite photos from Gmap 4 will help you find your way, keep you off avalanche-prone slopes, and avoid overly bushy slopes.

Much of the pre-trip planning here in Central Washington revolves around the very different weather and snow conditions we can experience in this region. The Cascade Crest gets huge amounts of snow and has milder wintertime temperatures. The Wenatchee Mountains by Mission Ridge are 42 linear miles from the crest and get dramatically less snow (about a third of what the crest receives). It’s also much sunnier, much windier, and substantially colder around Mission Ridge than at the crest. Other peaks on the eastern slopes of the Cascades fall between these two extremes. Places we access out of the Icicle Canyon like Mount Stuart (19 miles east of the crest) and Cashmere Mountain (11 miles east of the crest) may receive anywhere from 50 to 60 percent of the snow that Stevens Pass receives.

Because we can so easily access the Cascade Crest or different destinations in the shadow of the Crest, it’s rare that we can’t find a place to ski or snowshoe that is safe. Beyond safety, good planners can typically find places with a secondary benefit – e.g., a place with less snow to break (easier travel), better quality snow, better weather ( for a mood boost or for longer views), or better photography.

Over time everyone develops individualized pre-trip systems to help them plan for a safe, efficient, and fun outing. Here’s one approach:

Weather. First check the Wenatchee Outdoors Weather Matrix (‘Weather-Regional Links’ link in the Condition Reports) for the day(s) you’ll be out. Look at the expected weather and expected temperatures, from west to east, using the links in the matrix to see the seven day forecast at Stevens Pass, East Slope of the Cascades, Blewett Pass, and Mission Ridge etc. Knowing something about the present and expected precipitation and temperatures helps you make predictions about where you’ll I’ll be finding the best weather, safest weather, best snow for travel, safest snow for avalanches, most favorable temperatures for the day and more. This leads you to decisions about how much clothing will be needed, what kind of storm gear to bring, whether avalanche gear  is needed…

Snow Telemetry. Next, use the Snow & Ski Condition Matrix (in the Conditions Report) at WenatcheeOutdoors. Check the 7-day telemetry graphs for Stevens Pass, Lake Wenatchee, Tumwater Mountain, and Mission Ridge. Check the snow totals, 24-hour snow accumulation, and the wind data. Also look at the SnoTel for Blewett Pass to see how much snow fell here over the past week and over the past few days. Combining this snow information with the weather forecasts, gives you a lot of information about snow conditions, whether the avalanche hazard will be increasing or decreasing, where avalanche hazard will be highest. It will also help you decide where snow quality will be good or bad.

Condition Reports. For additional information that can confirm or rebut the opinions you’re forming, take a look quickly at the recent trip reports from Turns All Year (accessible from the Ski Condition Matrix that’s already open). See if anyone has a recent report from the area you’re thinking of visiting. Also look at the ‘Snowsports’ section of the WenOutForum to see what is being reported locally about snow conditions.

Avalanche Forecast. After all of the above, make your own prediction about the avalanche. Now check your forecast against the Avalanche Forecast from Northwest Weather and Avalanche Center (NWAC). Note the overall hazard and the elevations and aspects where the danger is higher. Also note the trend: during your day out will the hazard be trending to a higher or lower hazard. If you formed your own opinion of the hazard first, you’ll develop a better understanding of how avalanches work and how what elevates the hazard than simply looking at the avalanche forecast. If your forecast doesn’t align with the NWAC forecast, use this as a learning tool to see of you can figure out why.

Choose Appropriate Terrain.  First some definitions: white terrain = slopes under 20 degrees, green terrain = slopes between 20 and 27 degrees, yellow terrain = slopes between 28 and 34 degrees, red terrain = slopes between 35 and 45 degrees, blue terrain = slopes over 45 degrees. Now, using the avalanche forecast, define appropriate terrain. A simple tool here is to rely on the avalanche triangle. If the avalanche forecast is extreme (black), go hiking in the low lands, go downhill skiing, or visit low green or white terrain. If you do go out, make sure avalanches running down nearby slopes can’t overrun you. If hazard is high (red), visit white and green terrain. If the hazard is considerable (orange), this is grayer ground and much depends on the trend. If the avalanche trend for a region you're thinking about visiting is diminishing in hazard, low yellow terrain and especially low yellow ridges might be OK – green slopes are still preferred. If the hazard is moderate (yellow)  the terrain selection is still a bit ambiguous but if the trend shows the hazard is diminishing experienced winter travellers will often visit yellow terrain and make judgements as they go -- green terrain is still safer. If the hazard is low (green), this is the best time to visit yellow and red terrain. The Caltopo map system is really useful for helping find appropriate slopes and appropriate terrain.

Pick a Route. After all of the above, you’ll have a good ideas where the conditions of the day are best  (e.g., Cascade Crest, East Slopes near Leavenworth, Blewett Pass area, or Mission Ridge Area) and the steepness of the terrain you might safely visit. Now find a specific tour. The fastest option here is to open the indexes of the online guidebooks at WenatcheeOutdoors for ‘Skiing- Backcountry’ or for ‘Snowshoeing’. You can look at the complete index or use the Search Box at the bottom to sort out the trips in the region you want to visit. From the index you can open up the complete description of the route as well as the topographic map showing the route. View the map first to see if that route corresponds favorably with what you know about the current snow conditions, the current hazards, and the coming weather. Once you’ve found a promising route, read or print the full description for additional information like driving access, permits, etc. Double check the chosen route against the Caltopo map system to make sure the steepness of the terrain is suited to the hazards.

Map the Route. If exploring something new or ambitious, map the route you intend to follow – it’s much, much easier to do this at home where it’s warm and dry than in the field. Spread the map out, draw the route onto the map, measure the bearings to be followed, write important elevations on the map, etc.  A huge part of staying on course in the field is doing this homework. If you try to do all of this on the fly, windy weather, falling snow, fatigue, the reluctance to stop the party, and the need to hurry will frequently conspire against you and lead to navigation errors that can delay you at best or, at worst, get you really lost.  See the National Geographic Topo! CD maps  or the ‘Map’ tab at WenOut.

Estimate Time. The actual time a route takes is based on many variables (snow conditions of the day, the complexity of the route finding, the thickness of the vegetation you’re passing through, how many people are in your party (more people magnify stoppage times), the fitness of the weakest member of your party, etc. As you gain experience you’ll know how to add or subtract time from a basic system for estimating time. If your trip will be pushing the daylight available, make sure to have a headlight, essentials for making fire, and warmer clothing.

Here are some basics for a party with average fitness and intermediate ability:
  • on flat ground with firm snow and very gentle uphills, an average speed is about 2 miles per hour. 
  • on steady uphills in firm snow, plan on gaining about 1000 feet of elevation per hour. 
  • stops for rest, food, water, and clothing adjustments will cost 5 to 10 minutes per hour 4) on steady descents  you’ll cover ground about twice as fast or at a rate of about 2000 vertical feet per hour. 
  • allow about 30 minutes for a lunch break. 
  • if you’re breaking 12 to 18 inches of snow you may move at half the speed mentioned above unless you have a few really fit people who are strong enough to break the snow more quickly.

Night Before or Departure Day. Give yourself ten minutes of computer time shortly before you leave. Re-check the weather forecast, re-check the avalanche forecast, check the last few days of snow telemetry. Has anything changed to make you reconsider the general destination and specific trip?

Driving There. Finally as you’re getting close to the access point of your tour, pay attention to the slopes around you. What indications do you see of good snow, strong winds, and/or avalanche activity? Use this information to further fine tune plans and avoid hazards.



Our thanks to Cascade Subaru for helping get more people outdoors in winter and for  sponsoring the series of Self-Sufficient Snowshoeing classes where this information was presented.