I think a more accurate reading might be gotten with the thermometer sitting inside a fresh brewed Styrofoam cup. You are getting a surface temp exposed to the ambient temp. I used to develop my own slide film. It evolved a large glass thermometer as the water temp in the sink had to be darn close to what was called for. I had to warm the sink for quite a while to get a consistent temp reading and IIRC the thermometer instructions wanted a 3~4 minute submerfed exposure to give an accurate reading. I think you are going to need a probe to submerge in the coffee to get a true overall temperature reading.
Hotter still. But again, surface temperature.
I used a temp probe.
Tap water, and farking hot.
Brewed Water
I have a voltage meter with a temp probe. should I bring it tonight? LOL