Above is the upper air sounding from Omaha, Nebraska this evening (7:00 p.m. CDT, June 20th). While a great deal of information can be obtained from an upper air sounding we will focus on three things this evening. Over time I will point out other features. Down the right hand side is the altitude scale with thousands of feet on the right side of the scale. The wind barbs are also plotted vertically to the right. Winds are from the north and northeast up to about 5,000 feet. Above the winds are from the west and northwest. The red line is the temperature and the dashed green line is the dew point, both plotted vertically. At the time of the sounding Omaha reported temperatures in the upper 60s at the surface due to rain cooled air covering the area. Outside of the rain area temperatures were in the 90s (not shown here).
Notice how the red line is shifted left (cooler) near the bottom of the chart but quickly warms above the surface. This marks a low level inversion (region of cooler temperatures below warmer air aloft. The normal pattern of air being cooler with height is "inverted" due to cooling caused by evaporation of falling rain at the surface. The wind at the surface is from the north and northeast out of thunderstorms that were moving just to the north and northeast of Omaha. The outflow from these storms was moving to the west and south covering Omaha with a layer of cooler air. Above the cooler air the wind is from the west and is increasing speed with height.
To learn more about reading the feathers and arrows used to plot the winds refer to the home page of this website. Examples and an explanation are available at no cost.