When the cloud comes down

One minute you are admiring a distant ridge, the next the cloud has swallowed everything. On featureless moorland, low cloud removes your main navigation tool: the view. Familiar landmarks vanish, the horizon disappears, and every grassy hummock looks the same. This is when a map and compass stop being backup and become your primary means of getting home. The good news is that the skills are straightforward — setting the map, taking a bearing, and following a compass line — and they improve quickly with regular practice.

Setting the map

Setting the map means turning it so that its north lines align with the real world. You can do this with a compass in seconds. Lay the map flat on the ground or hold it level. Place your compass on the map with its edge along a grid line — an easting line works well. Keep the compass edge on that line and rotate the whole map, and the compass with it, until the red end of the magnetic needle sits inside the orienting arrow (often called "red in the bed"). Your map is now set. Do not move your feet while you do this if the wind is strong; kneel on the map corners if needed.

With the map set, you can relate what you see to the map. A stream ahead should run in the same direction as the blue line on the map. A spur should match the contour shape. In low cloud, this simple check stops you from walking off in the wrong direction before you have even taken a bearing.

Taking a bearing

A bearing is an angle measured from north. To navigate from A to B, you need the magnetic bearing to walk on. Start by placing the compass on the map with its long edge connecting your position to your destination. The direction of travel arrow must point towards where you want to go. Make sure the arrow is not pointing back along the line.

Now rotate the compass bezel until the orienting arrow lines up with the grid lines on the map. Ignore the magnetic needle for this step. Read the number at the index line — that is your grid bearing. Next, account for magnetic variation. In the UK this is small but not zero, and it changes slowly. Check the margin of your map for the current figure. If variation is, say, 2° west, add 2° to your grid bearing to get the magnetic bearing. If it is east, subtract it. Write the number down or repeat it to yourself.

To follow that bearing, hold the compass flat in front of you. Turn your body until the red needle sits in the orienting arrow. The direction of travel arrow now points along your magnetic bearing. Look up, pick a feature — a boulder, a patch of heather, a distant cairn — that lies on that line, and walk to it.

Following the compass line

Walking on a bearing in low cloud is a skill of small corrections. Keep the compass flat and check the needle every few steps. In wind and rain, it is easy to drift. Pick intermediate targets and walk from one to the next. If there are no features, use pacing and timing.

Count your paces over a known distance — say 100 metres — to find your personal pace count on that terrain. Then use it to measure distance as you walk. Timing works too: at 4 km/h you cover 100 metres in about 90 seconds, plus extra for ascent. But pace counting is more reliable on rough ground.

• Aiming off: deliberately aim a few degrees to one side of your target so you hit a linear feature — a stream, wall or path — and know which way to turn.
• Handrails: follow a wall, fence or stream that leads towards your destination, using the compass to confirm you are on the right one.
• Catching features: identify a large feature beyond your target, such as a loch or road, that will stop you if you overshoot.
• Back bearings: if unsure, take a bearing back to your last known point and check it matches the reverse of your outward bearing.

Practising in good visibility

The time to build these skills is not when the cloud is down and you are tired. Practise on clear days on familiar ground. Set the map at every junction. Take a bearing to a visible cairn and walk it without looking at the map again. Then check how close you got. Do it in wind and rain to simulate the awkwardness of a real winter day.

Regular practice builds confidence. You learn how your compass behaves, how many paces you take uphill, and how much you drift on a side slope. You also learn to trust the needle when your instincts say otherwise. That trust is what carries you across featureless moorland when the cloud is thick and the light is flat.

When it goes wrong

Even experienced walkers make mistakes. The common ones are simple: the compass was not held flat, a metal watch or phone interfered with the needle, the map was not set, or magnetic variation was ignored. If your bearing feels wrong, stop. Re-set the map. Re-take the bearing. Check for metal near the compass.

If you are genuinely lost, stop and sort yourself out. Put on an extra layer, eat something, drink water. Then navigate to a definite feature — a handrail — rather than wandering. Walking downhill is not a plan unless you know what is at the bottom. With a set map, a checked bearing and steady pace counting, you can walk out of low cloud.