Skywatch BL vs DewPtFm

The Skywatch BL is a complete weather station connected to your smartphone via Bluetooth Low Energy (BLE) and uses the Bluetooth Environmental Sensing Profile (ESP). Measurements are transferred to your smartphone and may be viewed or uploaded and stored online. This application supports the BL300, BL400, BL500 and BL1000: BL300: wind speed, temperature, humidity BL400: wind speed, temperature, humidity, pressure BL500: wind speed, temperature, humidity, pressure, UV index BL1000: wind speed, wind direction, temperature, humidity, pressure General features: • Real-time measurements • Graphical display of measurements • Measurement history • Display of measurements on a map • Wind speed units: km/h, m/s, fps, mph, knots, Beaufort • Temperature units: °C, °F • Pressure units: hPa, mbar, inHg • Modes: instant, minimum, maximum, average • Compatible Bluetooth Smart (BLE) 4.0 and newer. • Bluetooth Environmental Sensing Profile (ESP) and Environmental Sensing Service (ESS) • Online firmware update of the device • Menu languages: English, French Skywatch BL 300 features: • Windspeed • Temperature, wind chill • Humidity, dew point and heat index Skywatch BL 400 features: • Windspeed • Temperature, wind chill • Humidity, dew point and heat index • Pressure (QFE, QNH), altitude Skywatch BL 500 features: • Windspeed • Temperature, wind chill • Humidity, dew point and heat index • Pressure (QFE, QNH), altitude • UV index BL1000 features: • Windspeed, wind direction • Temperature, wind chill • Humidity, dew point and heat index • Pressure (QFE, QNH), altitude

This app computes the dew point temperature and relative humidity from a wet bulb temperature, dry bulb temperature and barometric pressure. If a barometer is not available a guess of 29.8 inches of mercury will usually give a near enough result. Temperatures are in degrees Fahrenheit and pressures in inches of mercury. Uses a computation method suggested by the National Weather Service of the National Oceanic and Atmospheric Administration, USA.