Get Temperature Value and Prompt an Action

I'm working with this case statement but am having difficulty getting the correct method of how to provoke a response based on the temperature data values. At the top I have defined a value

 float coldLimitTemperature = 10.0f;

I thought perhaps I would be able to follow along similar to how the LDR data was being processed.

 void MessageReceived(string message)
     {
         char type = message[0];
         string value = message.Substring(1);
 
         switch (type)
         {
         case 'T':
             //temperature sensor reading
             TemperatureText.text = TempSensorData.ToString ();
             TempSensorData = value;
             //Do Something If Temperature Falls Below 0 Degrees C
             // parse the input to a float and normalize it (range 0..1) (we could do this already in the Arduino)
             float TempInput = 1 - float.Parse (LDRdata) / 100f;
             if (coldLimitTemperature < 15.0f) {
                 print ("It's Chilly In Here");
             }
             //Do Something If Temperature Rises Above 90 Degrees C
             break;
 
         case 'L':
             //light sensor reading
             LDRdata = value;
             if(LDRdata == "") return; //if its empty stop right here
 
             // parse the input to a float and normalize it (range 0..1) (we could do this already in the Arduino)
             float input =  1 -  float.Parse (LDRdata) / 100f;
             // set the slider to the value
             float oldValue = slider.value;
             slider.value = input;
 
             // after the slider is updated, we can check for the other things for example play sounds:
             if (source.isPlaying) return; // if we are playing a sound stop here
 
 
             // else check if we need to play a sound and do it
             if //(slider.value > 0.9f && oldValue <= 0.9f) //This will call the voice no matter what time of day or night it is
                 (slider.value > 0.9f && oldValue <= 0.9f && (sysHour >= 18 || sysHour <= 06)) //Voice Will Only Activate between 6PM & 6AM
                 StartCoroutine(BrightnessResponse());
 
             else if (slider.value < 0.10f && oldValue >= 0.10f) //At These Values activate a "Darkness Detected" response
                 StartCoroutine(DarknessResponse());
             break;