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You are watching: How do meteorologists use isotherms and isobars

Isobars and also isotherms are lines top top weather maps which represent patterns of pressure and also temperature, respectively. They present how temperature and pressure are changing over room and so assist describe the massive weather patterns throughout a region in the map.

Why execute I care? Isobars and also isotherms make it less complicated to read and also analyze weather maps. By spring at fads of temperature and also pressure, you can determine weather conditions in the next few days ahead.

I should already be familiar with:Temperature,Pressure

What is an isotherm?

Isotherms space lines of consistent or same temperature. They are regularly used top top weather maps by meteorologists to offer a large scale check out of temperatures across the U.S. If friend have ever looked in ~ a weather map in a newspaper, the isotherms are supplied to division the color-filled temperatures. For example, in the map below, temperatures in the 60"s might be represented by a yellow color, while temperatures in the 70"s might be represented by one orange color. The line the divides the yellow from the orange is the isotherm. Every one of the locations between the 60 level isotherm and also the 70 degree isotherm will have actually a temperature in between 60 and 70 degrees.

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figure A: Temperature Isotherms (Image native NOAA) What is one isobar?

Isobars space lines of constant or equal push on a weather map. They can be supplied to find locations of short or high pressure over a large area (like the U.S.), and also they have the right to tell us just how intense the system might be. Top top weather maps, friend may have actually noticed locations that have actually a huge “L” or “H” over a region with lines circling around them. The “L” stands for low press (where we would suppose to discover the shortest pressure) and “H” means high press (where us would intend to uncover the highest possible pressure). The currently circling them are isobars. Generally the lowest push is where precipitation is most likely to fall, and also high pressures are usually linked with clear and also sunny conditions. Wherein the isobars are close together, windy problems may it is in expected. Elongated locations of low push on surface and upper wait weather maps are dubbed "troughs" and elongated areas of high pressure are referred to as "ridges."

number B: pressure Isobars (Image from for this reason why do we use isotherms and also isobars?

Isotherms and also isobars allow us come view huge scale processes much more easily than looking at the raw data from individual weather train station itself. For example, figure C is temperature data throughout the U.S. Number D is that the same data, but this time, colors and also isotherms have actually been added. Just by glancing, that is much easier to view where the warmest and also coldest temperatures will be across the U.S., and also it gives you one idea of what to intend in particular regions.