Plain English Meaning
A device that measures temperature and moisture in the air outside, and sends those numbers to a screen indoors so someone can read them from a distance.
Full Definition
A weather sensor that measures both air temperature and humidity at one location and transmits those readings to a display in another location, allowing observers to read the values without being physically present at the sensor.
Context Anchor
Seen in weather equipment descriptions, airport weather reporting, and maintenance notes for weather observing systems.
Derivation
Hygro- comes from Greek hygros meaning 'wet' or 'moist,' and thermo- from Greek thermos meaning 'heat.' A hygrothermometer measures both moisture and temperature. 'Remote reading' simply means the readout is in a different place from the sensor itself.
Why Pilots Care
Supplies accurate temperature and dew-point data used in METAR reports for flight planning and icing assessment.
Grounding Statement
The sensor can be outside in the actual air while the readout is inside where a person can safely and easily see it.
Intuition Check
Remote reading does not mean a person is far away guessing the weather. It means the sensor and the display are in different places.
Example Sentence 1
The field's RRH feeds current temperature and dew point into the hourly weather report.
Example Sentence 2
Before takeoff the pilot reviewed the latest RRH readings to confirm dew point spread.