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Term
Definition
relative humidity will decrease.
Feels Like
The Feels Like temperature is a combination of Heat Index when it is
hot outside, and Wind Chill when it is cold outside.
Wind Chill temperature is defined by the National Weather Service for
temperatures at or below 40 °F and wind speeds above 5.0 mph.
Heat Index is not valid or calculated below 80 degF.
Thus, when the outdoor temperature is between 40 degF and 80 degF,
the feels like temperature is the same as the outdoor temperature.
If the temperature is below 40 degF, the feels like temperature is the
same as the outdoor temperature when the wind speed is less than 5
mph.
Hecto-Pascals (hPa)
Pressure units in SI (international system) units of measurement. Same
as millibars (1 hPa = 1 mbar)
Hygrometer
A hygrometer is a device that measures relative humidity. Relative
humidity is a term used to describe the amount or percentage of water
vapor that exists in air.
Inches of Mercury (inHg)
Pressure in Imperial units of measure.
1 inch of mercury = 33.86 millibars
Rain Gauge
A rain gauge is a device that measures liquid precipitation (rain), as
opposed to solid precipitation (snow gauge) over a set period.
All digital rain gauges are self-emptying or self-dumping (also referred
to as tipping rain gauge). The precision of the rain gauge is based on the
volume of rain per emptying cycle.
Range
Range is defined as the amount or extent a value can be measured.
Relative Barometric
Pressure
Measured barometric pressure relative to your location or ambient
conditions.
Resolution
Resolution is defined as the number of significant digits (decimal
places) to which a value is being reliably measured.
Solar Radiation
A solar radiation sensor measures solar energy from the sun.
Solar radiation is radiant energy emitted by the sun from a nuclear
fusion reaction that creates electromagnetic energy. The spectrum of
solar radiation is close to that of a black object with a temperature of
about 5800 K. About half of the radiation is in the visible short-wave
part of the electromagnetic spectrum. The other half is mostly in the
near-infrared part, with some in the ultraviolet part of the spectrum.
Thermometer
A thermometer is a device that measures temperature. Most digital
thermometers are resistive thermal devices (RTD). RTDs measure
changes in temperature as a function of electrical resistance.
Wind Vane
A wind vane is a device that measures the direction of the wind. The
wind vane is usually combined with the anemometer. Wind direction is
the direction from which the wind is blowing.
Figure 56