Measured minimum temperatures in Boulder, CO show a strong cooling trend over the last 60 years, but NOAA massively tampers with the data to turn it into a warming trend.
The adjustments are as much as 7.8 degrees F.
If we look at daily temperatures for December, 1957 it becomes clear how wildly fraudulent NOAA adjustments are.
They lowered the average temperature for the month by 7.8F, and made the average temperature minimum nearly as cold as the lowest temperature for the month. Almost every day of the month was above the adjusted average. The adjustments would correspond to an elevation change of well over 1,000 feet – and the city of Boulder is basically flat. This is the sort of fraud which US Government energy policy is based on.