What are the highest dew points, worldwide and for the U.S.?

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Dear Tom,
What are the highest dew points, worldwide and for the U.S.?
— Denkmann
Dear Denkmann,
The world’s highest reported dew point is 95 degrees, recorded on July 8, 2003, at Dhahran, Saudi Arabia, located on the Persian Gulf. With a 95-degree dew point, the lowest possible heat index there (temperature also at 95 degrees) would be 161.
Surprisingly, one of the highest verified U.S. dew points was not observed on the Gulf or southeast Atlantic coasts, but at Moorhead, Minn., where weather historian Christopher C. Burt reports that it reached 88 on July 19, 2011. Other high but unsubstantiated U.S. dew points include 90 at Appleton, Wis., on July 13, 1995; 91 at Melbourne, Fla., on July 12, 1987; and 90 at the New Orleans Naval Air Station on July 30, 1987. Chicago’s highest dew point: 83 degrees on July 30, 1999.