Weather Stations and Weather Forecasts: Can You Do It Yourself?
OverviewHow do scientists know what the weather will be like in the future? In this fun weather lesson, students set up a weather station and collect data such as sky coverage, temperature, and rainfall. As they identify connections in their data, students will realize that these connections can help forecast what the weather will be like in the short-term future. The lesson culminates in students making and presenting a weather forecast for their fellow students.
- Can define and use the weather-related terms, variables, and instruments used in the lesson
- Can collect weather-related data and represent the data graphically
- Can explain how the weather is forecast using the method explained in this lesson
- Can explain at least one relationship between two weather-related variables
NGSS AlignmentThis lesson helps students prepare for these Next Generation Science Standards Performance Expectations:
- 3-ESS2-1. Represent data in tables and graphical displays to describe typical weather conditions expected during a particular season.
|Science & Engineering Practices||Disciplinary Core Ideas||Crosscutting Concepts|
|Science & Engineering Practices||Planning and Carrying Out Investigations.
Make observations and/or measurements to produce data to serve as the basis for evidence for an explanation of a phenomenon or test a design solution.
Analyzing and Interpreting Data. Represent data in tables and various graphical displays (bar graphs and pictographs) to reveal patterns that indicate relationship.
Using Mathematical and computational thinking. Organize simple data sets to reveal patterns that suggest relationships.
Engaging in Argument from Evidence. Construct and/or support an argument with evidence, data, and/or a model. Use data to evaluate claims about cause and effect.
|Disciplinary Core Ideas||ESS2.D: Weather and Climate.
Scientists record patterns of the weather across different times and areas so that they can make predictions about what kind of weather might happen next.
Patterns of change can be used to make predictions.
Cause and Effect: Mechanism and Prediction.
Cause and effect relationships are routinely identified, tested, and used to explain change. Events that occur together with regularity might or might not be a cause and effect relationship.
- Measuring instruments; one set per group or one set for the whole class. These instruments can be either made by the student or can be store-bought. Make your weather station(s) as complete as you can; a few easy-to-make or easy-to-obtain instruments are a good start. Consult the Teacher Prep section for hints on how to choose instruments.
- Thermometer; instructions on how to make a thermometer yourself can be found in this lesson.
- Rain gauge; instructions on how to make a rain gauge yourself can be found in this lesson.
- Anemometer; instructions on how to make an anemometer yourself can be found in this lesson or video.
- Optional: Hygrometer; instructions on how to make a hygrometer yourself can be found in this lesson.
- Optional: Barometer; instructions for homemade barometers can be found online. Unfortunately, homemade barometers tend to only work in temperature-controlled situations. For reliable measurements, you are better off with a store-bought instrument.
For the class:
- Graphing paper or tools to collect and graph data electronically, such as Excel or Google Sheets
- Optional: A few empty, flimsy water bottles with lids
- Optional: Poster board
- Optional: Huge cardboard box that can be transformed into a make-believe TV-frame.
- Optional: Equipment to enable students to make and display their own videos.
Background Information for TeachersThis section contains a quick review for teachers of the science and concepts covered in this lesson.
Meteorologists are scientists who study the layer of gasses surrounding Earth, called the atmosphere. The atmosphere is about 300 miles thick, and most of it is within 10 miles of Earth's surface. The weather is the reflection of what happens in this layer of air. Meteorologists help predict the weather by studying what happens in the atmosphere, more precisely, they follow changes in the air pressure, temperature, humidity, wind velocity, wind direction, etc., and apply physical and mathematical relationships to this information. They use weather connections (weather phenomena that frequently occur together) observed in the past to help predict the future. They also use weather patterns. A weather pattern is the repetition of the same type of weather on consecutive days. This works because the weather tends to repeat itself until something interrupts the pattern. For example, it can be clear and sunny for five consecutive days until a cold front brings a few days of cold, gloomy, and wet weather. A typical weather forecast is shown in Figure 1. Although these forecasts are often accurate, they remain educated guesses; these predictions are not guaranteed to occur.
A five-day weather forecast for San Francisco, CA during a week in August. The list has columns that describe the weather conditions, high and low temperatures, chance of precipitation as a percentage, wind direction/speed and humidity as a percentage for each day.
Figure 1. Five-day weather forecast for San Francisco.
Meteorologists collect a huge amount of data and use supercomputers to make their predictions. However, people have been predicting the weather for centuries without computers, and your class can too! With a knowledge of weather connections, one just needs to observe the current weather to be able to predict the future weather. Although these predictions are only valid for the near future, it is still exciting to be able to forecast the weather and it is a valuable skill to learn.
In this lesson, students collect weather-related data over a certain period of time. They set up a weather station to measure quantitative variables like temperature, precipitation, wind speed, etc., and collect qualitative data like cloud coverage. Students then graph their data and are challenged to confirm weather connections using their data. Finally, they use these connections to predict the weather.
Below is a list of weather-related variables with an indication of some global weather connections that are related to that variable. Notice that this is not an exhaustive list, and you might also find connections that are specific to your area.
Air pressure*, or how hard the air is pressing down on the Earth:
- Low air pressure indicates a change in the weather pattern.
- High air pressure indicates nice stable weather for the next 12 hours.
- Clear skies allow for bigger temperature changes between day and night. This happens because clouds reduce the passage of light and heat.
- White flat clouds (e.g. cirrocumulus clouds) high in the sky, as shown in Figure 2, mean stable air. The weather will stay as it is.
- Fluffy clouds (e.g. cumulus clouds) indicate that the air inside the cloud is rising. When these clouds are surrounded by blue sky, the weather will be fine in the coming hours. They can also grow into thunderstorm clouds. In that case, a storm is brewing.
- Thunderstorm clouds (cumulonimbus cloud) are huge towering clouds. They can be white at first but grow darker as time passes. These clouds bring thunderstorms. The darker the cloud, the sooner the storm will hit.
- Dark, low hanging clouds that cover the sky (nimbostratus) indicate a storm is close. Notice that normal wind patterns can drop just before a storm hits.
- Gathering, darkening clouds, as shown in Figure 3, indicate bad weather is coming. Dispersing and/or lifting clouds mean the weather is clearing out.
Figure 2. High clouds predict stable weather.
Figure 3. Gathering and darkening clouds predict rain.
Relative humidity* (often referred to as humidity):
- The relative humidity usually drops when the air heats up and rises when the air cools. This is why evenings and mornings can be damp (high humidity) and why fog (a very humid condition) often burns off over the course of the morning.
- If the humidity is higher than usual for your area, a storm or rain is probably on its way.
- A change in wind direction often brings a change in the weather pattern, except if that wind is light.
- The wind direction can also inform you about the type of air that is brought in. If you have the ocean to the north and a desert to the south, wind from the north will bring moist air and wind from the south will bring dry air.
- Other variables can help predict if the temperature will rise or fall. One needs the current temperature to make a more exact prediction.
- Storms are accompanied by higher speed winds.
- Precipitation is a variable that indicates what happened before. It is linked with the passage of or absence of a storm, rain, snow, hail, etc., in the past.
* Links in the additional background section provide more information on these variables.
Air pressure is a powerful predictor of the weather. Air is made up of gas molecules such as nitrogen, oxygen, and carbon dioxide. All of these molecules press down on the Earth, and this pressure is called air, or atmospheric pressure. At sea level, the air pressure ranges from 800 to 1050°millibars (23.6 to 31.0 InHg). Because warm air is less dense, it rises which results in lower air pressure near Earth. While it rises, air cools and, in the process, water vapor in the air condenses into liquid. This leads to cloud formation and rain. "Low pressure," therefore, is generally associated with cloudy and rainy weather. On the other hand, high-density cold air results in increased air pressure. As cold air sinks, it dries, causing dry weather conditions in "high pressure" zones.