THICKNESS AND TEMPERATURE GRADIENTS
METEOROLOGIST JEFF HABY
Notice the strong
temperature gradient (gradient of color) across the central U.S. on the
850 mb image below.
Temperature are much higher in the western Plains than in the eastern United States. Since
thickness is a function of the average temperature of a layer of air, then there
will be a thickness gradient in the same region that the temperature gradient occurs. This
thickness gradient can be seen on the thickness chart below (dashed lines). The thickness shown
1000 to 500 mb thickness. A forecaster will use these two model images
thermal advection. When strong thickness advection occurs, a forecaster
knows that thermal advection is occurring also. Warm Air Advection is occurring
across the central U.S. This is seen by the wind vectors at 850 mb moving the
isotherms toward the east over time. The thickness lines will move to the east
also in the central U.S.
Strong Warm Air Advection in the lower troposphere contributes to a
lifting of air.
Clouds and precipitation chances can be expected in these regions especially if
the air being lifted is saturated.
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