I had a lok at the min/max temperature in my old Poly Tunnel today. I haven’t reset it in about 2 weeks. It was interesting to see the variation in there. from -3°c to 27°c. Mild Sunny days a few weeks back reached 27 in the tunnel and last night was -3. I have reset the gauge and plan to keep a close eye on it. I also want to put one in the other tunnel to compare.