Overcast — Weather Glossary
A condition in which the sky is completely covered by cloud, typically defined as 8 oktas of cloud cover. Overcast conditions often occur beneath extensive frontal or stratiform cloud layers. Persistent overcast skies in the UK can limit daytime temperature rise and suppress nocturnal cooling. A UK-focused definition with clear usage notes for day-to-day forecast reading.
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Overcast — Definition
A condition in which the sky is completely covered by cloud, typically defined as 8 oktas of cloud cover. Overcast conditions often occur beneath extensive frontal or stratiform cloud layers. Persistent overcast skies in the UK can limit daytime temperature rise and suppress nocturnal cooling.
Deep Dive Summary
If the extended explanation is not provided for this entry, the key takeaway is still practical: Overcast clarifies how a forecast is framed, not just what is happening outside at one moment.
- Concept → implication, not concept → certainty.
- Trend matters more than snapshot.
- Regional exposure matters in the UK.
UK Forecasting Context
In WeatherEngland.com briefings, Overcast is used with a UK audience in mind: maritime influence, frequent fronts, and strong regional contrasts between exposed coasts and more sheltered inland areas.
You’ll often see it paired with short, practical cues (wind direction, pressure trend, cloud type), because those details explain how the day is likely to feel.
We keep glossary definitions consistent across our UK pages to support clear comparisons between England, Scotland, Wales and Northern Ireland.
Forecast Wording and Usage
In reports, this term is usually used to summarise the pattern in a single phrase, then followed by a practical consequence (for example, cloud thickening, showers becoming more organised, or winds freshening near a front).
- Often paired with a time cue (later today, overnight, into the weekend).
- Commonly accompanied by a confidence note when small shifts matter.
- Used to explain regional splits rather than to ‘decorate’ the forecast.
What It Usually Implies
The best forecasts explain cause and consequence. This term tends to sit on the cause side, so read on to the implied consequence (cloud thickening, showers sharpening, wind freshening, visibility lowering).
- Watch for paired terms (front, trough, inversion, airmass).
- Expect the cleanest signals in the first few days of an outlook.
- Use local radar/observations for short-term detail when variability is high.
How It Connects to Our Forecast Pages
This page is designed to be a quick lookup while you are reading a forecast. If the term appears on a city page, it is usually there to explain a change mechanism (fronts, mixing, stability), not to add colour.
If you want fast browsing, return to the glossary A–Z.
- Definition → context → practical implications.
- Consistent wording across cities.
- Related terms linked for deeper understanding.
If You’re Reading This, You May Also Need…
If Overcast is relevant in a forecast, it is often discussed alongside the concepts below. Reading them together usually gives a clearer, more complete interpretation.
Return to the main glossary for quick browsing: Weather Glossary (A–Z).