How to Navigate in Low Visibility
We've all been there; Confidently rambling about the mountains, at ease in the knowledge that we know exactly where we are. It's often all too easy to become complacent, especially when we're venturing on local ground and "know the hills like the back of our hands", we fall in to the age old trap of leaving the map and compass in the bottom of our bags. I've done it and you've done, it's more than likely that 99% of us have, and most of the time, we escape unscathed. But what happens when bad weather rolls in? What happens when we become enclosed by thick fog, snow storms or get caught offguard by the earlier, colder and darker nights that winter brings. Unable to spot landmarks or escape routes, how do we find our way when we can only see a few meters ahead?
Well, to answer the question we thought we'd ask the experts so went off to the Peak District to meet Trev and Dave from Edale Mountain Rescue Team. Here's what they told us...
Fail to prepare, prepare to get lost!
When we were chatting to Trev and Dave, one thing became very clear, be prepared! “Navigation starts at home,” they told us, and we’d be inclined to agree.
Know your route - before you head out for a hike, run or whatever the adventure might be, whether it’s local or unknown, you should always plot the route. Know where you’re leaving from, where you’re going and what the route and surroundings look like. Pick out features, landmarks or anything that could be used to locate yourself should the weather turn. Trev recommends setting checkpoints, having them written down or marked on the map so you can tick them off as you go. That way, if you do end up losing your bearings, you’ll have a much smaller space in which to re-locate yourself.
Plan escape routes - even during the summer here in the UK the weather can be unpredictable, you never know when a heavy cloud might descend and limit visibility. By planning where the nearest path back to safety is from any point on your route will ensure that should the weather turn, you know the best way to escape. Be mindful of where are the nearest buildings, roads or rivers are that will lead to safely back to civilisation.
Pack the right kit - yes, I know this isn’t directly about navigation (although a map and compass should be #1 and #2 on your list), but packing the right kit can make the difference between keeping calm in a whiteout and all out panic stations. Check the weather, and even if all looks well, a spare jacket for the cold and a head torch for unanticipated darkness will help prevent you getting caught off guard.
Tip #1 - Setting the map
Trev told us that many folks fall into the trap of trying to set the map by using features and landmarks. Done by sight alone, it’s easier than you might think to line up the wrong feature and start heading in the wrong direction, and in a situation where you can’t make out any features at all, this technique would be pretty darn difficult.
Your compass is your best friend when setting the map, whether you can see for miles or a mere few meters. Lie the compass on the map and rotate until North on the map lines up with magnetic North on the compass, that way, all the features (whether you can see them or not) will all line up and you can take a bearing for the direction you should be heading. A simple task, yet one that so often Trev and Dave see done wrong.
Tip #2 - Leapfrogging
Whether it’s a partner, friend or the bloke you met in the pub last night, navigating in low visibility is made much easier when there’s more than one of you. Here’s the situation:
You need to navigate across featureless ground. To complicate things, it’s misty and the visibility is low. You know your current location and have used your map to take a bearing of the direction you want to go, but know that attempting to walk on a bearing (whilst looking at your compass) is pretty much impossible to do accurately. The solution?… Leapfrogging.
With the bearing you’ve taken, send your most courageous companion on ahead, making sure they know to walk slowly and listen for your explicitly detailed directions of “left a bit… Stop there… Right a bit” to ensure they’ve walked and stopped in line with the bearing. If it’s windy and you can’t hear, use your arms to signal positioning, but make sure you discuss it before hand so you’re both on the same page. Walk on to where your buddy stopped and repeat the whole process until it’s either clear enough to make out features to follow or you make it back to safety.
Tip #3 - The five D’s
We’ve mentioned the four D’s before, but Trev’s tips include 5 (and an unofficial 6th).
Direction - What direction should you be heading in at different points in the journey? This could be an “approximately North-West” or a more precise “38 degrees.”
Duration - How long do you think it should take you to reach each notable feature or 'checkpoint' on your route? Being realistic helps for this step, and you should take terrain into account when estimating timings.
Distance - How far is it between each checkpoint on your route? This will also help to determine the duration between points.
Description - What does the route look like? What are the notable features that you can use as 'checkpoints' for each stage of your journey. Think inclines, flat terrain, marshland, forests, streams, valleys, walls, and roads. You should not only identify details of your route, but a few notable 'off-route' features to tell you that you've overshot or taken the wrong path too.
Destination - Where are you heading and what do you expect to find when you get there? Should you be looking for buildings and roads, or a more obscure spot like a part of a forest that looks great for an overnight bivvy.
The 6th (unofficial) ‘D’ that Trev told us about was Dangers. Is there anything in your route that you should avoid? Obvious dangers like cliffs and sharp drop-offs or other areas to avoid such as privately owned land.
Tip #4 - Head torch tips
Much like when using your full beams whilst driving, wearing a head torch in heavy fog can often worsen the visibility, which (believe it or not) can be counter intuitive. In a situation like that, Trev says the best thing to do is pull the torch down from your head to hang it from your neck. This has the same effect as dipping the beam in your car, it means the moisture in the air isn’t being reflected directly into your eyes, and opens up your field of vision. He also told us that using it down by your side as a hand torch is also just as effective, though makes it trickier to use the map at the same time.
There you have it. By no means not a fully exhaustive list of tips, but hopefully by watching the video and reading this you will have learnt a thing or two to help you survive if the weather closes in and you need to navigate yourself around in low visibility. If you're hungry for more, why not grab yourself a book to brush up on your navigation knowledge, we recommend either 'The Ultimate Guide to Navigation' or 'Navigation in the Mountains'... Happy reading!
We’d also just like to say a great big thank you to Trev and Dave from Edale Mountain Rescue Team for taking the time to help educate us on these tips. Mountain Rescue Teams all over the country have saved countless lives and continue to make our favourite playgrounds a safer place for adventures.