Barometric sensor data can be used for reading atmosphere pressure which is great indicator for future forecasting. Also barometric pressure is used to get altitude data. It is widely used in flying models, quadcopters and even parachutes. As you can see you can do lots of fun stuff with pressure data. R-B have shared an interfacing example of BMP180 pressure sensor to Arduino board.
He used Crowduino Uno board, which has several nice features like selectable power supply voltage between 3.3V and 5V, it also comes with SD card interface and few other improvements. Sensor module is interfaces via I2C interface. Data is displayed on small ILI9163 based TFT display. Several libraries were used to make things easier. Pressure module uses BMP180 library to get readings with few lines of code. LCD screen is also controlled with help of two libraries – TFT lib and Adafruit_GFX which takes care of generating fonts on graphical screen. Pressure sensor also comes with temperature meter which is also used for readings. So on LCD there are three parameters visible, barometric pressure, temperature and altitude. Altitude data needs to be calculated out of pressure readings. For this you need to know reference pressure level at sea level. And also you need to take into account other weather parameters like temperature and other patterns.