Temperature Report from Onset HoboWare

We went to the land yesterday afternoon and downloaded the data on our Onset Hoboware Temperature logger that we deployed on October 19th. We knew that we had a hard frost on the 20th of October, but we didn't know exactly what time and what temperature it was. We just knew that our grape leaves took a beating from the cold.
We set the device to measure and record data every ten minutes. So, the software associated with the temperature logger plotted the data like this:

All three of our data loggers trended in the same way:

In addition, I was able to look at all of the data and locate exactly when the coldest temperature occurred and what that temperature was. So, our three data loggers recorded the following low temperatures:

Logger 1	Logger 2	Logger 3
10/20 6:58 AM 28.139oF	10/20 6:32 AM 26.458oF	10/20 6:30 AM 26.245oF
11/03 7:18 AM 28.969oF	11/03 6:52 AM 27.930oF	11/03 6:45 AM 32.617oF

And the high temperatures occurred at these times:

Logger 1	Logger 2	Logger 3
10/21 3:28 PM 82.508oF	10/21 2:32 PM 78.624oF	10/21 3:30 PM 78.624oF
10/29 3:18 PM 83.399oF	10/29 1:32 PM 78.274oF	10/29 3:05 PM 78.098oF

The high temperatures seem a little too high in our opinion. We currently have our temperature sensors attached to our metal line posts and that might be creating a micro-environment due to radiant heating. So we are thinking about putting the sensors into a more neutral environment using PVC piping.