Hot Spots on a Clear Day

With high pressure fully in control over the Ohio River Valley today, it is a good chance to see some mesoscale (small scale) meteorology effects. Full sunshine across the entire region allows some areas to heat faster than others, based on small scale changes in topography as well as vegetation and urban effects. The satellite image below is an infrared image which takes a look at a different channel of radiation emanating from the Earth's surface. The purple shades in that image indicate more radiation, and in this case warmer temperatures, compared to the cooler blue colors.

The next image takes the same map and has the various automated surface observing system (ASOS) reported temperatures at the same time (Noon, Monday 9/14), colored with the yellow crosshairs. The orange crosshairs are for the three points in our area that are from the US Climate Research Network. Those in light green are from automated weather observing system (AWOS), and those in red are from the Kentucky Mesonet. In general the purple colors show warmer readings than those in blue shades, but the satellite imagery is 4 kilometer resolution, and smaller scale effects are possible, known as microscale meteorology.

The last image is just for reference, showing the visible image from the day and the clear skies across our region.

For comparison, linked below is a topographic map of the region, showing the various river valleys as well as some of the higher terrain across the region.