Maximum-minimum mercury thermometer

Bimetallic strip for a thermometer. When the temperature changes, the two pieces of metal expand and contract at different rates, bending the strip

Thermograph based on a bimetallic strip. The drum turns with time, recording the temperature on the paper covering the drum.

A recording thermograph.

A thermograph in an instrument shelter.

A National Weather Service shelter, with a standard height of 2 meters (~6 feet) above ground.

A shelter with door open.

Shelter temperature is different than the surface!

Illustration of contour lines for topography, but can apply to other quantities such as temperature and pressure.