Cloudspotting: Identifying Clouds and the Weather They Bring
We get some very varied weather here in the UK. From sudden downpours and gale-force winds to freak blizzards and scorching heatwaves, Britain’s temperate climate means we see cold, wet winters and warm, wet summers. This is great because it means our green spaces stay just that – green – all year long, meaning we can expect to see magnificent outdoor scenery at any time of year. So next time you think about cursing the Great British drizzle, remember it waters our gardens and provides us with some wonderful plants and stunning landscapes!
However, when we are outside, it can be rather annoying when the heavens open and we’re not well-prepared – it definitely leaves a dampener on the day. We thought we’d curate this handy guide to help our Grangers customers identify different kinds of clouds and what weather they bring with them. Obviously, we recommend checking the forecast beforehand but even the forecast can get it wrong. When you’re out on your adventures, foreseeing the kind of weather conditions clouds signify can be a real advantage - helping to keep you warm, dry and safe outdoors.
Clouds can be separated into three different categories based on altitude: low, mid and high-level clouds.
Low-level Clouds
Usually about 6500ft above sea level.
- Stratus clouds are low-altitude, white or grey blankets that shroud the sky. They are the lowest-lying of all the clouds and are associated with overcast days, however, they don’t tend to bring rain.
- Stratocumulus clouds are stratus clouds that have clumped together, creating a lumpy shape that indicates a change in the weather. It’s very rare for stratocumulus clouds to produce rain and, when they do, it’s normally a faint drizzle.
- Cumulus clouds are the most common, resembling a floating, fluffy cauliflower that’s detached from other clouds. Indicating fair weather, they’re normally spotted on sunny days. However, depending on the temperature, they can morph into cumulonimbus clouds.
- Infamous for bringing heavy precipitation and storms, cumulonimbus clouds are huge clouds that can spread between the differing levels of the troposphere, towering up into very high altitudes (you can’t really miss them). Their tops seem to resemble an anvil.
Mid-level Clouds
Between 6500 and 20,000ft above ground,
- Altocumulus clouds represent calm, clear weather and are layers or patches of cloudlets that are scattered across the sky. They do not produce precipitation.
- A thin layer or veil, altostratus clouds are featureless and are normally a blueish-grey colour.
- Nimbostratus clouds look quite ominous. A dark, thick, grey blanket rolled out across the sky can block out the sun and signal continuous rain or snow is heading your way.
High-level Clouds
Around 20,000ft+ above ground.
- Those wispy clouds that look like pulled cotton balls or tufts of hair scattered across the sky are cirrus clouds. They indicate a change in weather but don’t directly bring the change: they are so high up that their rain never reaches the ground. Instead, it re-evaporates and forms more clouds.
- Cirrocumulus clouds can have a honeycomb, scaley or ripple appearance that are formed from ice crystals. They are associated with dry, sunny weather as their precipitation cannot reach the ground.
- Cirrostratus clouds are thin veils of cloud that can cover all or part of the sky. Cirrostratus can indicate that persistent rain is coming, though it does not produce rain itself.
Hopefully, you are now a little more clued into cloud identification, so when you spot a cumulonimbus or nimbostratus, you’ll know to walk swiftly in the opposite direction and call it a day (unless you enjoy gallivanting in rain storms). Impress your friends and wow your family with your stellar cloudspotting skills: it will certainly earn you some cool points as an unusual party trick. But to really become an expert on all things clouds, check out the Met Office Cloud Classification, offering a more in-depth dive into the most common kinds of clouds we experience in the UK – and some of the more unusual ones. Remember, whatever the weather, you can keep yourself and your gear protected with Grangers.