wet-bulb temperature

[thomasal]

Hi!

There should be the possibility to calculate the wet-bulb temperature so that viewing the data of an unstaffed weather station you know if it's snowing or raining.
wet-bulb temperature < approximately 1.2°C => it's snowing
wet-bulb temperature < approximately 1.2°C => it's raining

Thomas

[AlaskaWX]

Hi!

There should be the possibility to calculate the wet-bulb temperature so that viewing the data of an unstaffed weather station you know if it's snowing or raining.
wet-bulb temperature < approximately 1.2°C => it's snowing
wet-bulb temperature > approximately 1.2°C => it's raining

Thomas

Your question about wet-bulb temperature intrigued me... So I wrote a meteohub plug-in weather station that can calculate the wet-bulb temperature using the values from the actual weather station sensors. The tricky part was to get the barometric pressure from the indoor sensor and the humidity and temperature from the outdoor sensors. I ended up using the meteohub datalogger protocol to pipe the needed values out of meteohub via wget and do the wet-bulb temperature calculations inside the plug-in weather station code. The plug-in weather station outputs the wet-bulb temperature as a t0 sensor and the values used in the calculations as a thb0 sensor.

After a little more testing I'd be happy to turn the gcc code and Makefile over to Boris to include it in future versions of meteohub...

Soon I'll post a link to a meteoplug chart from my live weather station that will show the wet-bulb temperature along with the values it was calculated from.

As you can see, I'm very interested in predicting snow where I come from!

Fred

[AlaskaWX]

Testing has been going well on my Wet-Bulb plug-in weather station. I have it up and running on an iConnect running meteohub 4.9t and feeding meteoplug the data.

Here is a link to the live meteoplug chart:

http://www.meteoplug.com/cgi-bin/meteoc ... 061f0a0628

The results agree favorably with this NOAA Wet-Bulb temperature calculator:

http://www.srh.noaa.gov/epz/?n=wxcalc_rh