Sigilla
Cabinet
Thunderstorm symbol, line drawing
Original line drawing. Not an agency logo, and not an emoji.

Thunderstorm

Also called thunder, thundershower, storm icon, lightning and rain

Forecast icon on a weather app or a public forecast table.

Forecast weather symbols

Thunderstorm meaning

A thunderstorm icon means thunder and lightning are expected, often with rain or a shower. A lightning bolt used as a motif is not this forecast.

At a glance

System
Forecast icon, with a station-plot note
Used for
Expected thunder and lightning
Not the same as
A lightning character, or plain rain

A forecast icon for thunder and lightning. Not a decorative bolt, and not ordinary rain.

The name. WWIS lists thunderstorms and thundershowers apart. A lightning bolt by itself is not this icon.

Download drawing

Where it comes from

WWIS lists thunderstorms and thundershowers as separate labels, and storm as another. The Met Office prints thunder showers by day and night, and a thunder icon. MetService describes thunder as one or more cumuliform clouds in which a discharge is seen as lightning and heard as thunder. Apple lists a thunderstorm icon apart from rain. A station that reports a thunderstorm is using an observing code. The code table is not printed in full here.

The line drawing is original to this cabinet. It is not an agency logo, a vendor icon, or the emoji for the same idea.

Weather

What it means

The forecast expects electrical activity. Rain may come with it. Hail may come with it. The icon is not a promise of both unless the service has said so. A thundershower, in the WWIS list, is the showery form. A lone lightning character in Unicode is a picture of a bolt, not a forecast that you will hear thunder.

Variants

Thundershowers

WWIS lists thundershowers beside thunderstorms. The Met Office’s thunder-shower icons are the day and night pair. A shower that thunders is not the same row as a storm they have labeled differently.

Questions

What does a thunder icon mean?

Thunder and lightning are expected. WWIS distinguishes thunderstorms from thundershowers. The Met Office draws thunder showers for day and night.

Is a lightning bolt a thunderstorm symbol?

Only when a forecast uses it as the storm icon. A bolt in a font, or a bolt drawn as decoration, is not a present-weather code and not a WWIS row.

Often confusedCloud with lightningCloud with lightning is a Unicode character. It has a code point. It is not a meteorological service’s thunderstorm icon.
Often confusedRainRain can fall with no thunder. The rain icon does not mean a storm.

Near this

Sources

Named when the entry depends on a text, a date, or a standard. Catalog numbers are not invented.

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symbol.wiki, edited as Sigilla. Last reviewed 18 October 2026. A reading of public tradition, not a ruling.