Anyone who's spent much time in San Francisco quickly learns the limitations of typical weather-forecasting apps: "Today's high 68 degrees" they'll say, and in return you'll scoff "Where?!"
Because of the city's hilly topography, water on three sides, and the movements of its famous fog, temperatures can vary widely depending on what part of the city you're in. You could leave your house near foggy Ocean Beach bundled in a jacket and scarf against temps in the mid--50s, then step off the train downtown where it's 70 and sunny.
One of the easiest ways to know what the weather is like across town is to just ask someone who's already there, but that's kind of a low-tech approach. BloomSky, a startup based in San Francisco, wants to build a network of personal, smart weather stations that you can ask instead.
Eye in the sky
The BloomSky mobile app will be free for anyone to use, but it pulls its hyperlocal weather data from a network of BloomSky weather stations--the company is currently beta-testing stations around the Bay Area, with input from a Stanford meteorologist on where to place them to cover the whole city of San Francisco.
The weather station, which was successfully funded on Kickstarter, contains an HD camera that's pointed at the sky and takes photos every three to five minutes, dawn to dusk. It's also packed with sensors to measure the UV index, humidity, barometric pressure, temperature, and rain fall.
The weather station's outdoor module can be staked into the ground or mounted to a roof, wall, balcony, or patio, and an optional solar panel can be mounted alongside to provide power. All the data is sent up to the cloud over your home Wi-Fi network, along with the images captured by the HD camera, which can pivot up to 45 degrees so you can find a nice patch of sky to watch.
If you don't want the BloomSky community to be able to see a time-lapse video of your weather station's images, you can opt out of that part, while still sharing the rest of your weather data. But the time-lapse videos, created automatically at sunset, are pretty nice. This one was shot in Sunnyvale, a town in Silicon Valley:
A little cloudy
BloomSky isn't inventing the personal weather station. Weather Underground already aggregates data from 16,000 personal weather stations as well as more official sources, and Netatmo sells a personal weather station that integrates with an iOS app.
In fact, BloomSky's app will use data from those Weather Underground stations for the first year while building up its own network. But BloomSky thinks its approach of including time-lapse photography of the sky will give its users a more emotional connection to the weather than they'd get from other apps. You can even get push notifications when the weather is about to change at the location of your BloomSky module--handy if you need to run outside and take the laundry off the clothesline.
Still, BloomSky's longevity will depend on getting enough people to install the $170 weather stations to supply enough crowdsourced data for good weather predictions. To do that, the company is marketing the devices to businesses as well as individuals. A bed and breakfast on the Northern California coast, for example, could use a BloomSky weather station to brag to potential visitors about the lovely climate, while also giving them a sneak peek of the view.
BloomSky is expanding its beta program in August (interested Bay Area residents and businesses can apply here), and plans to ship the outdoor module, as well as an indoor module and accessories, this December. Until then, just do what the San Franciscans do: Dress in layers, and always keep a scarf in your bag.