Weather is what the atmosphere is doing over hours or days in one place — "the weather turned wet by Thursday". Climate is the long-run pattern of that weather in a region, measured over decades — "Lisbon has a mild Mediterranean climate". A cold morning is weather; a place being reliably cold in January is climate.
The core difference: timescale
Both words describe the same physical thing — temperature, rain, wind, humidity — but at different resolutions. Weather is the snapshot: what you look out of the window and see, what the forecast covers, what changes by the hour. Climate is the statistical summary: what those conditions average out to over a long stretch, conventionally thirty years or more.
Because of that, weather is unpredictable beyond about a week, while climate is describable in advance. You cannot say what the weather will be in Cairo on 3 August next year, but you can say with confidence that Cairo's climate makes it hot and dry.
Using each one
- The weather was against us all weekend. (one specific stretch of time)
- Northern Scotland has a wetter climate than the south-east. (a settled long-term pattern)
- A single storm is weather; a shift in how often storms arrive is climate.
The test you can run
Try adding today or this week to the sentence. If it still makes sense, the word is weather: "the weather today" works, "the climate today" does not mean anything useful. Then try adding over the last fifty years. If that fits, you want climate.
The old shorthand is worth remembering because it is exact: climate is what you expect, weather is what you get.
Why the distinction matters
Most public confusion between the two shows up in one argument: a cold snap being offered as evidence against long-term warming. That mixes the scales. A single freezing week is a weather event, and climate describes what those events average to across decades — so one cold spell no more disproves a warming trend than one tall child disproves an average height. The reverse holds as well: a record-hot afternoon on its own is weather, not proof of anything.
The figurative senses
Both words have well-established non-meteorological uses, and here the same logic applies. Climate means the prevailing mood or conditions of a situation — the political climate, a climate of fear, the current economic climate. It always implies something settled and background.
Weather shows up in phrases about coping: weather the storm (to survive it), under the weather (mildly unwell), make heavy weather of something (to make it harder than it needs to be). Note that weather as a verb also means to wear down by exposure — weathered stone, a weathered face.
Frequently Asked Questions
Is a heatwave weather or climate?
A heatwave is weather — it is a specific event with a start and end date. Whether heatwaves have become more frequent or intense over decades is a question about climate.
Can I say "the climate today"?
Not about the atmosphere. "The climate today" only works in the figurative sense, as in "the business climate today". For actual conditions outside, use "the weather today".
What is the difference between climate change and global warming?
Global warming refers specifically to the rise in average global temperature; climate change is the broader term, covering that warming plus the resulting shifts in rainfall, storms, sea level and seasons.