Why did we make the MeteoHelix weather station message format public?

We decided to release the MeteoHelix weather station message format and its Java-Script decoder code as open-source because of a wide array of customer requests. Our customers have very wide ranging applications for weather data.

We will keep offering our allMETEO web portal platform as the default data solution for the MeteoHelix IoT weather stations. Making the MeteoHelix weather station message format public will enable 3rd parties, which to not wish to use the allMETEO cloud, to build their own software applications and mobile apps as they see fit.

Being the only micro-weather station to meet the World Meteorological Organization (WMO) measurement precision standards for climatology and meteorology makes the MeteoHelix an ideal platform for research and high-density climatic networks. Its data can be reliably used by national weather services for precision weather forecasting. Opening up the communication protocol will enable meteorological, oceanographic and private organizations to bring real benefits to their customers.

Build your own weather app with the MeteoHelix

MeteoHelix IoT Pro LoraWAN smart-cities application for urban climate and urban heat island monitoring

MeteoHelix IoT Pro LoraWAN smart-cities application for urban climate and urban heat island monitoring

Type = 1, MeteoHelix wireless message format (11 byte for 10min transmit intervals)
bits2 bits5 bits11 bits6 bits6 bits9 bits14 bits10 bits9 bits8 bits8 bits
Physical propertyMessage typeBatteryTemperatureT_minT_maxHumidityPressureIrradiationIrr_maxRain (revolving counter)reserved
UnitsV°C°C°C%PaW/m2W/m2Rain gauge dependent
Resolution10. gauge dependent
Minimum value03 V-100 °C00050000 Pa000
  • T_max & Irr_max values are added to the Temperature and Irradiation readings which are currently set to be 10min averages of 15sec measuring intervals.

  • T_min is subtracted from the Temperature reading. (Future versions of the MeteoHelix will feature 10 or 5 second measuring intervals.)

  • Sensor Error or N/A = Maximum possible value for the physical property which in binary = 111111…. (FFFFF…. In hex)

Web based & Excel spreadsheet weather data message decoder/verifier

The Things Network Payload Decoder

MeteoHelix weather station payload message decoder JavaScript code can be pasted directly into your application on The Things Network LoRaWAN console.

Paste the unmodified javascript code into the decoder section of your the things network application.

Paste the unmodified javascript code into the decoder section of your the things network application.

Sigfox Network Payload Decoder

For Sigfox wireless network based MeteoHelix weather stations, this JavaScript code can be integrated into your application which receives the MeteoHelix message payload from the Sigfox Backend.

Open-Source Decoder JavaScript Code

Decoder for LoRaWAN and Sigfox MeteoHelix weather stations for message type = 1.

var pos = 0;
var bindata = "";

var ConvertBase = function (num) {
    return {
        from : function (baseFrom) {
            return {
                to : function (baseTo) {
                    return parseInt(num, baseFrom).toString(baseTo);

function pad(num) {
    var s = "0000000" + num;
    return s.slice(-8);

ConvertBase.dec2bin = function (num) {
    return pad(ConvertBase(num).from(10).to(2));

ConvertBase.bin2dec = function (num) {
    return ConvertBase(num).from(2).to(10);

function data2bits(data) {
    var binary = "";
    for(var i=0; i<data.length; i++) {
        binary += ConvertBase.dec2bin(data[i]);
    return binary;

function bitShift(bits) {
    var num = ConvertBase.bin2dec(bindata.substr(pos, bits));
    pos += bits;
    return Number(num);

function precisionRound(number, precision) {
  var factor = Math.pow(10, precision);
  return Math.round(number * factor) / factor;

function Decoder(bytes, port) {
  bindata = data2bits(bytes);
  //if(bytes.length != 12) return {"status": "ERROR", "describtion": "11 bytes are required"}
    Type =  bitShift(2);
    Battery = precisionRound(bitShift(5)*0.05+3, 1);
    Temperature = precisionRound(bitShift(11)*0.1-100, 1);
    T_min = precisionRound(Temperature - bitShift(6)*0.1, 1);
    T_max = precisionRound(Temperature + bitShift(6)*0.1, 1);
    Humidity = precisionRound(bitShift(9)*0.2, 1);
    Pressure = bitShift(14)*5+50000;
    Irradiation = bitShift(10)*2;
    Irr_max = bitShift(9)*2;
    Rain = precisionRound(bitShift(8), 1);
    CO2 = precisionRound(bitShift(8)*5+300, 1);
  decoded = {
    "Type": Type,
    "Battery": Battery,
    "Temperature": Temperature,
    "T_min": T_min ,
    "T_max": T_max,
    "Humidity": Humidity,
    "Pressure": Pressure,
    "Irradiation": Irradiation,
    "Irr_max": Irr_max,
    "Rain": Rain,
    "CO2": CO2

  return decoded;