(KFVS) - How much will temperatures fall during the eclipse?
When we give 'temperatures' during the weather forecast, we are talking about the temperature of the air.
During the daytime hours, the air is heated mainly by contact with the ground surface.
When the eclipse begins, incoming solar radiation will gradually be reduced to zero, and then will slowly increase again after the totality.
At some point, this will result in a cooling of the ground surface and a drop in air temperatures, but meteorologists are not certain just how much.
Or to put it more accurately, it may depend on where you are located.
Data shows temperature drops of 15 to 30 degrees during previous total eclipses, but those were recorded mainly in drier climates and during cooler times of the year.
A significant temperature drop like that is not likely to happen here in the Heartland because of our expected high humidity levels. Humidity, clouds and even wind tend to limit temperature decreases.
Another complication is that the air is not directly heated by the sun, but by contact with the ground. So in urban areas where there is a lot of concrete (which tends to hold heat) temperatures may drop less than in rural areas.
The consensus here among the KFVS weather team is that our temperatures will slowly drop somewhere between 5 and 10 degrees depending on where you are watching.
In fact while most people will be looking up at the sky, some of us will be watching our weather instruments to see exactly what happens on Monday, Aug. 21!