• areas of high and low pressure
• surface troughs and surface ridges
• well developed fronts
• areas of warm and cold advection
• general wind flow and areas where wind speeds are faster and slower (tight pressure gradients)

• Contents
• Sea Level Pressure in millibars
• Green
• Every four millibars (996, 1000, 1004, etc)
• Temperature in degrees Fahrenheit
• Yellow (Dashed), for Black Backgrounds
• Red (Dashed), for White Backgrounds
• Every five degrees (80, 85, 90)

The areas where the temperature lines are very close together represent what might be a front. Is it also located in an area where the pressure lines (isobars) are strongly curved? If it is, you've most likely found a front. Learn the rules for finding fronts.

Areas where the isobars are close together, or packed, are areas of fast winds. The closer the isobars, the greater the pressure difference and the stronger the difference, the stronger the winds are in that region.

Areas in which one finds pressure lines intersecting temperature lines are often areas where warmer or colder air is being advected. In other words, if air is flowing from an area of warmer air into an area of colder air, the warmer air is being advected. When isotherms and isobars intersect, the atmosphere is considered to be baroclinic. Watch for changing conditions over the next several hours and days.

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