Twin States Weather Blog

Interesting Weather Ahead

* Watching the radar as patchy light drizzle continues to move southeast through the northern part of Mississippi. Nashville, Tennessee reported light snow last hour at 34 degrees. We'll only see patchy drizzle around here, with the best shot being along and north of Highway 16.

* Still keeping an eye on the system moving through here Wednesday night. Latest runs of the GFS and NAM both bring some precipitation in here:

0z GFS Valid Midnight Wednesday Night

0z NAM Valid Midnight Wednesday Night

The 1000-500 millibar 540dm (the southernmost blue dashed line) is pretty close to us, and that is a very rough "first-guess" of the rain/snow line. This line shows us where the AVERAGE temperature of the atmosphere from the surface to around 18,000 feet is below freezing. The problem with this value is that we often see situations where extremely cold or warm layers in the atmosphere skew the average. For example, consider a scenario where the lowest half of the atmosphere is 10 degrees above freezing and the upper half of the atmosphere is 10 degrees below freezing. The AVERAGE temperature is exactly freezing -- but the bottom half of the atmosphere is well ABOVE freezing!

In the setup Wednesday night, temperatures in the lowest 5000' will be above freezing, so the snow should melt on its way down. Bottom line is that we expect only rain with temperatures in the upper 30's. If our thoughts should change, we'll of course update things.

* The rain clears out Thursday afternoon, and we begin a slow warming trend by late week.

* Will post tomorrow with more on the upcoming Southeast Severe Storms Symposium!

posted by WTOK Weather Staff @ 11:45 PM