This inspired me to lookup the hottest rain event as I had a memory of it being set a couple of years ago. 119F in Imperial Valley. Dew at the time was only 58.
https://www.wunderground.com/cat6/Hottest-Rain-Record-Rain-falls-119F-Imperial-California
This article says highest recorded dew was 95 in 2003 in Dhahran, Saudi Arabia.
https://wgntv.com/weather/weather-blog/ask-tom-why/what-are-the-highest-dew-points-worldwide-and-for-the-u-s/
It was supposedly 108 at the time, for a heat index of 178!
https://www.washingtonpost.com/news/capital-weather-gang/wp/2015/07/30/iran-city-hits-suffocating-heat-index-of-154-degrees-near-world-record/
Back in 95, Appleton WI was 101/90 for a heat index of 148.i
https://www.wunderground.com/blog/weatherhistorian/record-dew-point-temperatures.html
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