Soil temp sensor question - cold climate...

[jg]

I sent the following email to Davis support but figured someone on here would might know the answer (it warmed up to 3 degrees this morning here in Maine):

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I've got a soil temperature (and moisture) probe combo up in Maine, zone 4b.  Right now it is 1.6 degrees, average temp over last week has been 27.2, 27.9 over the past 28 days and the adjacent lake has been frozen for about a month.

The soil temperature probe, which is at 4", has been "stuck" at 33 degrees for nearly a month, it dipped to 32 for a day but there was about an inch of rain and mid-30 degree temps a week ago that pushed it back to 33.

There is about 8 inches of snow on the ground, even if you dig the snow away the ground feels frozen solid.  Is there an explanation as to why the temperature reading is staying at this point?  Does it "stop" around freezing?

The web page for the station is here:
http://www.jgweather.info/StowWeather/index.html 

If you click on "Weather Alamanac" you get a lot more historical data.  Thanks in advance.
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[jg]

Just an update about a month later.  Soil moisture shot up to 200 and even with relatively warmer temps its down to 29 (snowpack shrank to about 4-5 inches).  2 feet is going to come down today so I doubt the temp will go lower.

[Steve]

I don't know why I didn't see your previous post, but until recently, we hadn't had low enough temps to answer your question, anyway. The lowest I've seen is 31˚ a couple of weeks ago. And like you've noticed, the soil moisture reads open and shoots to 200 when the soil reaches freezing.



My soil data page: http://www.avon-weather.com/soil.html