John Metcalfe was CityLab’s Bay Area bureau chief, covering climate change and the science of cities.
Bask in the sublime beauty of “Karl,” the city’s chilly miasma, with these always-updated satellite images.
It’s cold and cottony, sails over the city like the gloomy mist preceding a ghost invasion, and even has a name, “Karl”—San Francisco’s lovely fog, arriving each summer to smother the horizon and the hopes of sun-loving beachgoers.
Now locals and anyone worldwide can check in on Karl’s current condition thanks to Fog Today, which pulls detailed scans from NOAA’s new geostationary Earth-observation satellite, GOES-16. The site presents static images taken with the last five to 10 minutes and also loops from the previous day, so you can watch the fog spread silently, but often explosively, over the coastline and into the San Francisco Bay. (Unfortunately it does not process nighttime images, because the dark-induced noise makes it look like locusts are overrunning the city.)
Logan Williams, an Open Lab Fellow at BuzzFeed who lives in east San Francisco, built the site partially out of love for West Coast weather. “Watching the fog flow in is beautiful, and seeing it flow over the hills is an experience many in the Bay Area cherish,” he says. “With these satellite images, we can watch the macro-scale view as well, and it’s equally fascinating—atmospheric eddies, rivers, and ripples revealed through our fog.”
There’s also a practical side to Fog Today. The summertime miasma—formed by moisture-rich ocean air hitting seasonally colder coastal waters and shifted winds, and aided into the Bay by the welcoming geography of the Golden Gate—can quickly transform pleasant, bright excursions into struggles through Silent Hill streets. There’s a reason visitors often hear the quote falsely attributed to Mark Twain: “The coldest winter I ever spent was a summer in San Francisco.”
“Summer weather forecasts for the Bay Area are sometimes not very useful, because everything depends on the fog,” says Williams. His tactic is to use public-access websites like NOAA’s to keep an eye-in-the-sky view, because “fog dictates so much of the Bay Area's weather, and it was so easy to see,” he says. “And I saw an opportunity to make this easier for other people.”
But for whatever reason people visit Fog Today—to ooh and ahh or to predict when to pack a jacket—Williams hopes they’ll recognize the value of technologies used to study weather and climate, which could face funding cuts under President Trump’s proposed budget.
“I think it can be too easy to forget that a lot of the things we take for granted, including accurate weather forecasts, are a result of government investment in technology and its maintenance,” he says. “I wanted to remind people of that and also raise awareness of the politicization of these useful, and economically valuable, satellite systems.”