Forecast Weather: Elements of Weather and Instruments Measuring Them

When it comes to forecast weather, you will easily see that various factors are included. Air temperature, humidity, and winds are the factors you most often see or listen to in a weather forecast, right? Of course, they are all important elements of the weather that meteorologists use to observe, measure, and forecast weather. Check out this post to learn more and find out some essential instruments for forecasting the weather!

Understand weather forecast

Elements of Weather and Their Influences

Weather consists of different elements. The ways that these elements interact with each other create different weather events. 

Let’s take a deeper look at each of the most common weather elements listed below to see what they are and how they affect the weather. 

Temperature

Normally, the temperature is one of the very first elements mentioned in a weather forecast or a weather report. It measures the degree of the coldness or hotness of a place from day to day. 

During the day, the temperature may change repeatedly depending on the angle of the sun.

It’s a very important element of weather and clearly influences other weather elements like wind, precipitation, clouds, and more.

Temperature is a key factor in weather forecast 

Humidity

In a weather report, we also often see the percentage of humidity. That’s the relative humidity. Another type of humidity is absolute humidity, which is measured in g/m3 (grams per cubic meter).

Simply, humidity is the amount of water vapor present in the air at any specific time. Though humidity normally can’t be seen, we can feel it.

Not only does humidity influence our physical comfort levels, but it also plays a big part in weather formation and can be used to forecast weather events like a coming storm, for example.

Humidity

► Read more: How does humidity affect weather?

Atmospheric pressure

Atmospheric pressure or air pressure is another important element of weather, particularly when it comes to changing atmospheric conditions. 

Changes in atmospheric pressure are mainly caused by the descent of cold air and the rise of warm air.

More specifically, atmospheric pressure is the result of the pressure that is created by the weight of air in Earth’s atmosphere.

Atmospheric pressure

Do you know that the air has weight? In fact, the air is filled with small particles of oxygen, nitrogen, carbon dioxide, and more. The weight of these particles creates pressure because of the gravitational force of the Earth. 

Air (atmospheric) pressure is highest on the Earth’s surface and decreases at higher altitudes.

Wind

Wind is one of the major driving forces of weather that meteorologists deeply take into account when forecast weather. In fact, the majority of weather events, including extreme ones like thunderstorms and hurricanes, … are driven by wind.

Wind

Wind is defined as the large-scale movement of air from areas of high air pressure to areas of low pressure in the atmosphere. 

Also, the strength and speed of wind are determined by the difference in air pressures as well as the distance between the high-pressure areas and low-pressure areas.

Precipitation

Precipitation is water (liquid or frozen water) forming in the atmosphere and falling back to the Earth. Precipitation comes in many different forms, such as rain, snow, mist, sleet, fog, …

Precipitation

Together with condensation and evaporation, precipitation is one of the major parts of the global water cycle. Precipitation can be predicted by observing clouds and other signs in the sky.

Clouds 

A cloud is simply a large collection of tiny water droplets or ice crystals that form after the water reaches condensation level and does not remain in gaseous form anymore.

It’s important to study clouds with scientific equipment to forecast weather conditions. Different types of clouds determine different weather conditions. (read more: Types of cloud and their characteristics).

Clouds

For example, dark heavy clouds indicate that there will be thunderstorms or heavy rain, while light clouds indicate little or no precipitation.

Sunshine duration

Sunshine duration (also referred to as sunlight hours) is simply the length of time that the Earth’s surface is exposed to solar radiation. This element of weather is normally measured in hours per day or per year.

Sunshine duration influences other elements of weather like temperature, humidity, and air pressure as well.

Sunshine in summer

Visibility

Visibility may not clearly seem like an element of weather. Still, it is also mentioned in weather reports or weather forecasts, especially when discussing and measuring weather conditions like mist, fog, smog, or freezing drizzle. 

It’s a measure of the distance at which light or an object can be clearly observed. 

Visibility

Above are 8 elements of weather and their effects on the weather, in general, and on other aspects of weather, in particular. Let’s move on to the next part of this article, where we will learn about instruments used to measure these weather elements and forecast weather.

Instruments for Measuring Elements of Weather

To measure and forecast weather conditions, meteorologists use a wide range of instruments. Read on to know which instruments are used to measure different elements of weather.

Measure air temperature

The thermometer is used to measure the temperature in degrees Celsius and degrees Fahrenheit. Thermometers come in all sizes and shapes and date back to the 18th century.

A thermometer

Mercury, bimetal, and electronic thermometers are among the most commonly used instruments for measuring air temperature. They are usually kept 6 feet above the ground in a white box under the shade to record the temperature of the day.

Measure atmospheric pressure

Barometers are the instruments used to measure atmospheric pressure in units of millibars. Similar to thermometers, barometers also come in different forms, such as mercury, aneroid, water, and digital barometers as well. 

The very first barometer was invented in 1643 by Evangelista Torricelli - an Italian physicist and mathematician.

A barometer

Under most conditions, low and falling pressure indicates poor weather, while high and rising pressure is an indicator of sunny weather. That’s how atmospheric pressure helps meteorologists to forecast weather.

Measure humidity

To measure the humidity or the amount of water vapor in the air, meteorologists use an instrument called a hygrometer. Like thermometers and barometers, we can also find more than 1 type of this instrument.

A hygrometer

One of the very common humidity measurement instruments is the psychrometer, which uses one wet bulb and one dry bulb thermometer to measure the relative humidity of the atmosphere.

Measure precipitation

A rain gauge is used to measure the amount of rainfall. It’s a measured container that captures the rain and measures the amount of rain falling over a period of time.

The standard rain gauge has a long, narrow cylinder that’s capable of measuring rainfall of up to 8 inches. Other rain gauges collect the rain and weigh it, then later convert this measurement into inches.

A rain gauge

Measure wind

The next instruments used to observe and forecast weather are the anemometer and wind vane (or weather vane). While the anemometer is used to measure wind speed in miles per hour, the wind vane is used to measure wind direction at any given time.

The anemometer consists of three (or four) cups fixed to a mobile shaft. When the wind blows faster, then the cups spin around faster. The actual wind speed shows up on a dial. Besides, there’s also another type of anemometer that uses a propeller (not cups) to accomplish the same function.

The wind vane

About wind vane, it’s a flat-shaped object (normally a weighted arrow) that spins freely on a fixed axis and points east, west, north, or south. This instrument can be found on top of a weather station.

Measure clouds 

Meteorologists use a device named Ceilometer to measure the cloud. This instrument is used to measure the height of the cloud as well as to determine natural aerosol concentration in the atmosphere.

Weather satellites and weather radars are advanced instruments that meteorologists use to study clouds in detail. Satellite and radar images help accurately measure cloud density, the movement of clouds, and the amount of moisture….

A Ceilometer

Measure the sunshine duration

Another instrument used to observe and forecast weather is the Campbell Stokes Recorder. 

Meteorologists use this device to record sunshine duration, and because of this, sometimes, the Campbell Stokes Recorder is also referred to as a sunshine recorder.

This weather instrument basically consists of a spherical lens that focuses the sunlight on a specific type of tape and then makes its measurement of how many hours the sun shines on the day.

The Campbell Stokes Recorder

Measure visibility

To measure visibility, meteorologists use visibility sensors such as "forward scatter sensors," for example. In the past, it was the standard to use our own vision (our eyes) to measure the degree to which an object can be observed.

Others

In addition to the basic weather instruments mentioned recently, meteorologists also use many other devices to measure and forecast weather elements. Some of them are weather balloons, disdrometers, lightning detectors, snow gauges, and many others.

Conclusions

That’s all about some of the most common elements of the weather, their influences on other weather elements, as well as their effects on the weather as a whole. Together with that, we also explore some of the most popular instruments used to observe and measure each element of the weather when it comes to forecast weather. Hope that you find all of the information in this article interesting and useful.