I submit two charts for your examination:
According to the top chart, temperatures in southeastern Michigan were about 4° F above normal. Yet, tracking the month for this suburban Detroit location revealed a variance of plus 1.6°.

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I'm not complaining about the weather we had, especially after the really nasty February and March.
But these inconsistencies continue to confuse me. Perhaps the weather monitoring station NOAA uses for this area is next to the jet tarmac at Metro Airport.
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