Dewpoint Quits Reporting Below -40


#1

My weather station in Glasgow, MT quit reporting the dewpoint temperature after it hit -40 degrees. This was an accurate reading. The ambient air temperature was in the -20s and -30s. The serial number of my AIR is AR-00004064. Hardware Revision: 1. Firmware Revision: 20.


#2

What is the Humidity reading?


#3

Looking at the data this morning, it looks like all the data backfilled and now shows the dewpoint down to -46F. At the time the dewpoints initially quit reporting the RH still looked right with a number right around 50%. I’ll keep an eye on it and see if it drops out again.


#4

Your humidity is fine. This issue is that no temperature below -40 will be displayed.

e.TemperatureValue.prototype._isValid = function(e) {
return !(e > 85 || e < -40)
}

So I am guessing this test is also being applied to Dew Point. At this minute your Dew Point is -42 C.

@dsj will need to confirm if this is a bug or a feature.


#5

I see your dew point is showing on the graph as soon as it hit -40 again.


#6

David @dsj Will you look at this? I understand the what and why. Is there a way to report and graph dew point when it is below -40 since it’s a legitimate value?