How far away is the storm? The flash-to-bang method can help.

When lightning is made by a storm the rapid heating and expansion of the air create the thunderclap. But because sound travels slower than light, there's a gap between seeing the lightning and hearing the thunder it produced. Using Distance = speed x time, by counting the seconds from seeing the lightning you can easily estimate how far away it is.

Conveniently, the speed of sound in air is about 330 metres/second. So depending on your unit preference:

every 3s you wait the thunder travels about 1 km

every 5s you wait the thunder travels about 1 mile

Give it a try at a safe distance from your next lightning storm.

Also see: thunderclap or rumble, thunder clouds, dirty thunderstorm

Flash-to-bang method

Heat islands are urban areas that can have higher temperatures than surrounding rural areas with more greenery.

Heat islands are caused by a number of factors including:

the types of materials we use in cities for buildings, pavement, and roads that can absorb more heat than natural surfaces such as leaves or grass

human additions to the sun's heat such as air conditioning, vehicles, cooking, or machinery

that shapes of our cities that may restrict airflow to carry heat away

the mass of our buildings that can absorb heat and release it gradually, even through the night

More natural, often rural areas with greenery may reflect more light, release moisture and provide shade.

There are ways to help reduce the effect of heat islands such as planting more urban trees, or using green roofs.

Deciduous trees have the handy feature of providing shade for a house in the summer while letting light through in the winter when the leaves fall.

A study using 2015 data found that "doubling tree cover in European cities could cut the number of heat-related deaths during summer months by nearly 40 per cent."

Heat islands

Banner clouds can form on the side of a high or exposed peak and seem to stick to the mountain face like a banner, even on an otherwise cloudless day. There are several theories for how they form but in general strong winds of cold dry air from one side likely interact with warmer humid air on the other. Look out for them next time you're in the mountains.

Also see lenticular clouds, thunder clouds, and more clouds.

Banner cloud

If weather is like the money in your pocket on any one day, climate is like your net financial worth over time.

I liked this simple analogy to distinguish between weather and climate in a New York Times article by Kendra Pierre-Louis. While there are many causes of extreme weather, keeping this analogy in mind helps keep some overall context even when you’re in the midst of an unexpected cold snap.

Weather and climate: an analogy

Are caused by the Earth’s tilt. As the Earth goes around the sun, the tilt of Earth’s axis — 23.5 degrees — causes at different times of the year, the two hemispheres, North and South, to be either tilted towards the sun or away from it.

In winter, and closer to the poles, because light from the sun hits at a greater angle, the solar energy gets spread over a larger area. This makes it weaker, and cooler and gives rise to winter.

In summer, and closer to the equator, light from the sun hits more directly and so is concentrated on a smaller area making it stronger.

The tilt also means that the number of daylight hours is greater in the summer than in the winter, and hence the amount of time it gets heated, which also contributes to the seasons.

Seasons are reversed in the two hemispheres, so if it’s winter in the Northern Hemisphere it’s summer in the Southern and vice-versa. The further from the equator you go, the bigger the effect of the seasons. So, temperatures in Ecuador stay relatively constant throughout the year, while the poles experience extremes of 24-hour daylight or 24-hour night and great freezes and great thaws.

Seasons

Nature’s greatest snow machine, where crazy amounts of snow can fall in huge snowstorms on the downwind — leeward — side of a lake. Where the effect is pronounced, such as on the East of some of the Great Lakes in the US, it can generate regions known as snow belts because of the amount of snow they receive.

It works kind of like this: cold air blows over a lake. As the cold air passes over the warmer lake it picks up water vapour from the lake and it warms. This causes it to rise and in turn cool, such that when it reaches the downwind side of the lake it is now a lot of cold moist air which can cause some incredible snowstorms, like 2–3 inches of snow per hour. Satellite pictures like these show it in action pretty clearly. If the land rises after the lake the air can cool faster and increase the effect — and also cause a rain shadow — and if there’s a whole lot of convection and the air is rising fast you can get what’s called thundersnow — a thunderstorm in a snowstorm. I know.

Find weather interesting? Me too. You might also be interested in: Dirty thunderstorms, thunderclouds, yesterday’s weather (applying weather forecasting to software engineering), rain shadow, lenticular clouds, know your cirrostratus from your altocumulus, and British weather.

Lake-effect snow

Caused by ash and rock interacting inside a cloud instead of ice particles. As you can imagine you can get this with volcanoes which can be pretty spectacular. Here’s more about how lightning forms inside a thunder cloud, the regular kind.

Dirty thunderstorm

Thunder clouds are so impressive. Lightning forms due to air currents in the cloud as warm moist air rises up quickly. All the collisions between particles cause different charges to develop between the top and the bottom of the cloud. When that gets large enough, kapow!

Also see: thunderclap or rumble, dirty thunderstorms.

Thunder clouds

I learned about this nice principle from agile software development. Basically, that when thinking about how much you’ll get done next week, what you got done this week is a good proxy. Sure this week was different because you had that external presentation and an offsite, a bug to fix on live and Amy was sick. But the reality is things will interrupt you next week too. Just like the weather, what happened before is a good first guess at what will happen next.

Yesterday’s weather

California is a nice example both stitching up the Central Valley and Nevada. And in Washington State if you need a bit more sunshine, just try driving East.

Rain shadow

Make spectacular photos like these, these, or this, but generally mean high winds high up. Look out.

Lenticular clouds

Stratus: layers AND Cumulus: heaps + height + Cirrus at the very top and you’re a long way already.

Sketchplanations tagged with weather