Does anyone else use an infrared....

thermometer to take temp readings of water. I am sometimes surprised by what I would guess the water temp to be and what it actually is.

5 to 6 to 7 ft under the surface

– Last Updated: May-04-13 5:07 PM EST –

Might "look" warm on the surface to the thermogun.
Actually dangling toes a few feet down....another story.

Thermocline in effect.

sure, but
The IR thermometer gives faster readings than any immersion unit, but, as pointed out, that doesn’t tell us much about deeper water, and for our purposes, a submersible that can lower to, say 6 ft is too expensive, bulky, etc to be practical for paddlers.

So all paddlers are ony 4 ft tall…?

– Last Updated: May-05-13 8:25 PM EST –

What happens when a 6 ft paddler falls out of their boat,
--do you think the toes on that person feel cold water ?

Be real - it's an unrealistic gauge of the water temps.

Take a standard thermometer, tape it to a filled nalgene,
throw it over the side, tethered on a string, BELOW the water surface.
Much, much cheaper and far more accurate of paddling conditions

Used thermoguns 100 times a day developing thermoplastic parts
and they are great for surface temps only, 1mm deep maybe.

Limits of Infra Red thermal sensing
Infrared Sensors work best with black body, carbon structures. They work poorly with shiny metal surfaces and liquid surfaces. For copper tubing its always best to color the surface with a black grease pen. For liquids they are just poor. Best to shoot the same flat object submerged in the liquid long enough to reach water temperature.

Every year I have people concerned that their domestic hot water system is faulty because their Infra-red thermometer is showing different temperatures all over their piping system. The Rocket Scientists at MIT that designed the early and expensive Micro-Scanner supplied a Nisan black grease pencil with each unit and detailed directions on using it with different materials. Directions more detailed than those supplied by Harbor Freight and others.


I bought a $4 Harbor Freight digital thermometer, stuck the probe lengthwise through a wine cork and float it in my kayak scupper. After you push the button, it stays on for a couple minutes before shutting itself off. Works just fine for surface temps.

Water temp
I just use a digital meat thermometer, accurate enough, only care about the first couple of feet, cause that’s all I’m using. tkamd