I got my new Tempest and set it up next to my Davis VP2 Plus and noticed that some of the readings are way off and none of the readings match my VP2. I know my VP2 is old and may not be 100% accurate but some of the Tempest readings seem way off. Yesterday it was showing UV readings of 11.6 and in general the UV and solar readings seem high. The rain seems to be way low almost like it’s off by a digit. This morning my VP2 was showing .21 ‘’ and the Tempest was showing .02 ‘’. With the Tempest being new and all I hope it’s just something that can be fixed with firmware updates to calibrate things to be a little more accurate. It’s the perfect little form factor but to be honest I’m a little disappointed. 
No need to have new firmware, calibration can be done and will be done. UV etc will have a calibration after some time (for UV you need several full sunny days at least for it to calculate the adjustment).
Just let it run a few days and according weather you have, calibrations will start to kick in, some might need a little more time.
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i would expected that by now, the factory calibration would be much better, most notably for UV.
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