Tim from Portage asks: What is the perfect circle on the radar the last two nights?
Answer: It sounds like you may have been witnessing ground clutter as a result of an inversion. On a clear night, when a radar is in clear, air mode and there is calm weather, there is super-refraction due to an inversion; which is where temperature near the surface increases with height. A strong inversion can cause an increase in back-scattered radiation which can make it look as though there is an abundance in radar returns.
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