Fog Emoji

A low, horizontal band of gray haze. Depending on the platform, the design is a cloudy rectangle, a swirl of mist, or, on older Apple renders, the Golden Gate Bridge disappearing into fog. 🌫️ is Unicode's answer to the question "how do you draw low visibility?"

The emoji does two very different jobs. Half the time it's weather (coastal fog, airport delays, atmospheric photography). The other half it's cognitive: brain fog, the clinical and informal shorthand for trouble concentrating. A 2024 RECOVER study found 64% of Long COVID patients report cognitive symptoms commonly described as brain fog, and the emoji has become the default visual for those posts.

There's a third register, smaller but persistent: mystery, noir, and confusion. A detective post. A horror movie review. "I don't know what's happening in my life right now 🌫️." Meteorologically, fog is defined as visibility under 1 km (3,300 ft); mist is 1 to 2 km; haze is 2 to 5 km. The emoji doesn't care about those numbers, but the feeling is the same: something is in front of you that you can't see through.

Approved in Unicode 7.0 (2014) as U+1F32B FOG.

Three registers, in rough order of volume on X and Instagram:

Brain fog and mental health. Since 2020, this has quietly become the dominant usage. Long COVID posts, ADHD content, perimenopause threads, chronic fatigue communities, antidepressant side-effect check-ins. A 2024 Northwestern study found 86% of Long COVID patients in the US report brain fog compared to 15% in India, a gap researchers attribute mostly to cultural reporting norms, not disease severity. The emoji tracks US/Western usage patterns closely.

Weather. Morning marine-layer photos from San Francisco (locals call their fog "Karl"), airport-delay complaints, atmospheric mountain shots, moody autumn content. Pilots and weather accounts use it precisely: 🌫️ in a METAR context means visibility below 1 km.

Mystery and noir. True-crime posts, horror reviews, Sherlock Holmes and Jack the Ripper content, "foggy memory" captions. Less common than weather or brain fog, but consistent.

It's rarely flirty, rarely funny. The default vibe is slow, heavy, and a little sad.

🌫️ came through the same 2011 emoji ad-hoc push that added 🌡️, ⛈️, and the rest of the weather family. Unicode approved it in version 7.0 (June 2014), and Apple, Google, and Microsoft all shipped it in 2015 as part of Emoji 1.0. It sits in the "weather-ti" subcategory next to 🌀 cyclone and 🌬️ wind face.

Apple's early fog design did something unusual: it reused elements of the much older 🌁 Foggy emoji (which depicts the Golden Gate Bridge) and added a simple gray band on top. That design decision is why 🌫️ is still informally tied to San Francisco on older iPhones. Later redesigns moved to abstract mist. Samsung and Google went purely abstract from day one.

The brain-fog meaning was not a planned use. The term "brain fog" appeared in medical literature as early as the 1990s, but it was COVID-19 and specifically Long COVID that made it mainstream. Usage of 🌫️ in that register spiked in 2021 and has stayed elevated since, because the symptom is durable and the community discussing it is large.

1. 1272King Edward I bans sea-coal smoke in London after complaints about health. The city's industrial fog problem predates Unicode by 742 years.
2. 1905A Londoner coins the word "smog" to describe fog mixed with coal smoke, in a paper delivered at the Public Health Congress.
3. 1952The Great Smog of London kills an estimated 12,000 people over 5 days in December, prompting the 1956 Clean Air Act.↗
4. 2011Unicode's Emoji Ad-Hoc Committee proposes fog in L2/11-052 alongside the rest of the weather symbol family.↗
5. 2014Unicode 7.0 approves U+1F32B FOG.↗
6. 2015Apple, Google, Samsung, and Microsoft ship the emoji in Emoji 1.0.
7. 2020COVID-19 pandemic makes "brain fog" a household term. 🌫️ starts appearing in Long COVID threads and mental-health content.
8. 2020Emoji 13.1 ships 😶‍🌫️ Face in Clouds, a ZWJ sequence combining face-without-mouth with fog.↗
9. 2024Nature-published research links Long COVID brain fog to serotonin depletion, giving the metaphorical emoji a mechanistic basis.↗

• •The foggiest place on Earth is the Grand Banks off Newfoundland, where cold Labrador Current water meets the warm Gulf Stream and produces 206 foggy days a year, per Guinness World Records.
• •San Francisco's fog has a name: Karl. The nickname was popularized by a Twitter account started in 2010. At its peak @KarlTheFog had over 350,000 followers. The account went quiet in 2022, but the name lives on.
• •A 2024 RECOVER study found 64% of Long COVID patients report cognitive symptoms, typically described as brain fog. The underlying mechanism appears to involve serotonin depletion triggered by persistent viral antigens.
• •The Great Smog of London in December 1952 killed roughly 12,000 people over five days. It was coal-smoke fog, not natural fog, but the visual is what most people picture when they think of London mist.
• •The word "smog" was coined in 1905 to describe fog mixed with coal smoke. "Pea-souper" came from the yellowish-green tint tarry soot added to the mist.
• •The 😶‍🌫️ Face in Clouds emoji is a ZWJ sequence that literally combines 😶 face-without-mouth and 🌫️ fog. It was added in Emoji 13.1 in September 2020, just as brain-fog discourse was going mainstream.
• •Fog is classified in meteorology into at least seven types: radiation, advection, upslope, evaporation, precipitation-induced, freezing, and ice fog. Pilots are required to distinguish them because they behave differently.
• •California's Tule fog is a dense radiation fog that forms in the Central Valley after winter rains. It's the state's leading cause of weather-related fatal car accidents.