Even with cutting-edge satellite, radar, and computing technology, weather forecasters still get it wrong quite often. Predicting the weather is just that difficult. So you shouldn’t expect Redditor DowntownBass4556’s miniature weather forecasting device to give you perfect answers all of the time. But even if you occasionally find yourself without an umbrella on a rainy day, this little gadget is still worth building. It’s unique and looks like it would be lots of fun to play with.
The device is powered by a low-power, 8-bit ATtiny85 microcontroller. It collects barometric pressure and temperature measurements using a BMP180 sensor. A push button is used to generate a forecast based on this data, which is displayed on a small monochrome LCD. The energy-sipping microcontroller makes it possible to power the entire system with a single coin cell battery. All of the hardware is assembled on a prototyping board.
When getting started, the user first enters their present altitude for calibration. This is done by using the button to increase the value in 100-foot increments (good luck with that if you’re hiking in the Rockies!). Once that has been set, a button press will generate a new forecast using the Zambretti algorithm. The approach uses atmospheric pressure trends to predict short-term weather.
Unfortunately, there is no build guide at this time. However, the hardware design is very simple, the parts are highly accessible, and the Zambretti algorithm is easy to implement. Using this project as inspiration, it would not take long to make a clone of it.
