Knowing how to read a weather map can help you understand the weather and predict it. For example, the sky will be clear in an area of high air pressure (H), and storms may occur in an area of low air pressure (L). The blue "cold stretch" line carries rain and wind in the direction indicated by the triangle. The red "hot stretch" line carries brief rains followed by warm temperatures in a semicircular direction. If you want to learn more about how to read a weather map, keep reading!
Step
Part 1 of 4: Learning the Basics of Weather Maps
Step 1. Understand the basic concept of precipitation
Most people will notice the precipitation. In meteorology (the study of the weather), precipitation is any form of water that falls to the earth's surface. The forms of precipitation include rain, hail, snowfall, and rain of water mixed with snow.
Step 2. An important aspect of weather interpretation is the ability to understand the effects of differences in air pressure
The implication of a high air pressure system is dry weather, while low air pressure is associated with humid air, and the possibility of precipitation.
- High air pressure is an air mass whose air content is denser, so that the air is cooler and/or drier than its surroundings. Thus, the heavier air falls down and away from the center of air pressure - like water being poured onto the ground. In high air pressure systems, the weather will tend to be sunny.
- Low pressure systems are air masses that are less dense because the air is more humid and/or warmer. The surrounding air is drawn inward towards the center of low pressure air like a lighter hot air balloon flying upwards. As a result, clouds or precipitation often develop as the humid air gets cooler as it rises upwards. You can see this effect when invisible water vapor is forced to condense into water droplets when it comes into contact with the cold exterior of the glass. However, water droplets wouldn't form if the glass wasn't so cold…so the low pressure air rising upwards can only produce rain if the air is cold enough to condense the water vapor into droplets of water which are then too heavy for the flying air to hold. to the top. (Simply put, clouds are water droplets that are light enough to stay high).
- In very low pressure systems, a hurricane is imminent (if there isn't already a hurricane). Clouds begin to form and move in the sky - thunder clouds form when moist air is pushed very strongly. Sometimes, tornadoes form when very high pressure air collides with very hot, humid low pressure air.
Step 3. Study the weather map
View information about the weather in TV news, online media, or local newspapers. (There are various other sources such as magazines and books, but the information may not be up to date). Newspapers are a convenient way to find weather maps because they are cheap, reliable, and can be cut to carry around while learning to interpret symbols.
Step 4. Analyze a small section of your weather map
If possible, look for a map that covers a less extensive area - interpretation will be easier. Focusing on a larger scale map is likely to be difficult for beginners. Pay attention to locations, lines, arrows, patterns, colors, and numbers on the map. Every sign is important and they are all different.
Part 2 of 4: Reading Air Pressure
Step 1. Understand about the size of air pressure
Air pressure is the weight or air pressure against the ground measured in millibars. The ability to read air pressure is important because the pressure system is related to certain patterns of weather.
- The system's average air pressure is 1013 mb (759.8 millimeters of mercury).
- Powerful high-pressure systems are typically 1030 mb (772.56 millimeters of mercury).
- Low-pressure systems are typically 1000 mb (750.1 millimeters of mercury).
Step 2. Learn the symbols for air pressure
To read barometric pressure on a surface analysis weather map, check isobars (iso = equivalent, bar = pressure) – curved lines indicating areas of equal air pressure. Isobars play an important role in determining wind speed and direction.
- When isobars form closed concentric circles (which are not always round), the smallest circle in the center represents the center of air pressure. The air pressure can be a high pressure system (denoted by "H" in English, "A" in Spanish) or a low pressure system (denoted by "L" in English, "B" in Spanish).
- Air does not flow "down" the pressure gradient, but "around" it due to the Coriolis effect (rotation of the earth). Thus, the wind direction is shown by isobars counterclockwise around low air pressure (cyclonic flow), and clockwise around high air pressure (anticyclonic flow) in the Northern Hemisphere. As a result, wind is formed. The closer the distance between the isobars, the stronger the wind.
Step 3. Learn how to interpret Low Air Pressure Systems (Cyclones)
Storms of this kind are characterized by increased cloud cover, wind, temperature, and the possibility of precipitation. On weather maps, storms are represented by isobars that are close together and arrows pointing clockwise (southern hemisphere) or counterclockwise (northern hemisphere), usually with a "T" in the middle of the isobars, forming a circle. round (the letters can vary, depending on the language from which the weather report is presented).
Radar images can show a low air pressure system. Tropical cyclones (South Pacific) are also known as hurricanes in America and beyond, or Hurricane in the coastal region of Asia.
Step 4. Learn how to interpret the High Air Pressure System
These conditions indicate sunny and calm weather and reduced chances of precipitation. Dryer air results in a greater range of high and low temperatures.
On a weather map, such a system is indicated by an isobars with an "H" in the middle of the isobars and arrows indicating the direction the wind is blowing (clockwise in the Northern Hemisphere, counterclockwise in the Southern Hemisphere). Like cyclones, such air can also be displayed with radar imagery
Part 3 of 4: Interpreting Different Types of Stretch
Step 1. Observe the type and movement of the stretch
Stretch marks the boundary between warmer air on one side and cooler air on the other. If you are close to the stretch, and the stretch is moving toward you, there will be changes in the weather (such as cloud formation, precipitation, thunderstorms, and winds) as the stretch boundary moves past your location. Mountains and large bodies of water can distort the path along the stretch. You will see some lines on the weather map that have a semicircle or a triangle on one side, or both (as shown in the image). The symbols indicate the boundaries of various types of stretches.
Step 2. Cold stretch analysis
With these various weather patterns, the possibility of heavy rainfall and high wind speeds. The blue line with a triangle on one side shows the cold stretch on the weather map. The tip of the triangle shows the direction of movement of the cold stretch.
Step 3. Heat stretching analysis
Hot stretches often result in a gradual increase in rainfall as the stretch approaches, followed quickly by sunny and warm weather after the stretch has passed. If the warm air mass is unstable, it is likely that the weather will be characterized by prolonged thunderstorms. The red line with a semi-circle on one side indicates heat dissipation. The side of the semicircle shows the direction in which the hot stretch is going.
Step 4. Study the trapped stretch
Trapped stretch is formed when cold stretch meets hot stretch. This stretch is associated with a variety of weather events (probability of thunderstorms, depending on whether it is a heat or cold trap. The passage of trapped slag usually carries drier air (lowering the dew point). Purple lines with semicircles and triangles on the same side represent stretches whichever side of the symbol is trapped, that is the direction that the trapped stretch goes.
Step 5. Analysis of stationary stretching
This stretch represents an immovable boundary between two different air masses. This kind of stretch has long periods of continuous rain over a fairly long period of time in an area and travels in waves. The symbols of a semicircle on one side and a triangle on the other indicate that the stretch is not moving anywhere.
Part 4 of 4: Interpreting Other Symbols On Weather Maps
Step 1. Read the station model at each observation point
If there are station models on your weather map, each one represents the current temperature, dew point, wind, sea level pressure, air pressure trend, and weather with a set of symbols.
- Temperature is usually expressed in degrees Celsius, while rainfall is recorded in millimeters. In the United States, temperature is expressed in Fahrenheit, while precipitation is measured in inches.
- Coverage of clouds is indicated by a circle in the center, the range of filled circles indicates the degree of cloudiness in the sky.
Step 2. Study the lines on the weather map
There are many other lines on the weather map. The two most important line types indicate isotherms and isotach.
- Isotherms – The lines on a weather map connecting points through which isotherms have the same temperature.
- Isotach – The lines on a weather map connecting the points that the isotach passes through have the same wind speed.
Step 3. Analyze the air pressure gradient
The number on the isobars, for example "1008", is the air pressure (in millibars) along the line. The distance between the isobars is called the air pressure gradient. A large change in air pressure over a short distance (or adjacent isobars) indicates strong winds.
Step 4. Analyze wind strength
The wind arrow indicates the direction of the wind. Lines or triangles that go outward from the main line at a certain angle indicate wind speed: 50 knots for each triangle, 10 knots for the full line, and 5 knots for the half line.
Tips
- Isobars can be bent by high natural landmarks such as mountains.
- Don't be confused by the complexity in front of your eyes when reading a weather map. The ability to read weather maps is a valuable skill that should not be taken into account.
- If you're interested in learning more about weather features and systems, you might consider joining the local meteorological community.
- Weather maps can be based on satellite and radar imagery, recordings from equipment at weather stations, and computer analysis.
- stretch most often comes from the center depression.
