I just got mine two days ago and have it setup within 10 mins. When I put the remote unit and main unit side by side, their reading are not the same. Don't worry, as I just hold the main unit to setup the date and time. After a while, the reading are exactly the same. I noticed that the first line reading indicate there will be rain, but the outside it's still full of sunshine. I guess this display just something for fun, not for real. But guess what, this morning I wake up, there have been 1 hour raining last night!! Even the whether channel didn't forcast the rain!! I love my new toy. I set the main unit in my upstair bedroom, and the remote unit on my backyard deck. It's about 10 meters away, I can read the temp and humidity anytime on my main unit. I highly recommend this toy.