Not commenting on Newark itself, there's enough folks doing that, but I had that problem with my old Vantage Vue, it was very evident on sunny days, but not all sunny days. It tended to happen in the spring more than any other season for some reason. I could never pinpoint the exact conditions when it would happen but when it did there was no doubt when comparing it to my other thermometers and other local readings. The Vue has no FARS but Newark must so its not a direct comparison.