northgawx

*disclaimer: the following is not a forecast ,just my thoughts at this time*

 

So, chances are you have seen or heard at least something about the potential for snow this week. This is my take on the next 72 hours. 

 

The energy that we will be watching closely can be seen in the blow image just entering the grid on the left.

 

THis wave is expected to move into northern Mexico/Southern Texas by tomorrow and into the western Gulf of Mexico by Tuesday. 

 

 

The big questions then arise as to what actually happens at the surface thanks to this wave. The models have been ALL over the place for the past 48 hours but as of the current 12z runs are beginning to come more in line for a threat of wintry precipitation for all of GA/SC/NC, SE TN, and SE/EC AL. It is looking increasingly likely for areas especially along and south of I-20 to see a major winter storm, with snow/ice/sleet all falling in places that is hasn’t in a VERY long time. For us north of I-20, however, things are a bit more tricky though certainly more hopeful than the models seem to be depicting. 

 

First, lets take a look at the total precip between now and Wednesday from the GFS/NAM

 

 

As you can see, they are in fairly good agreement on a rather sharp cutoff from a lot of precip to none just south of the I-20 corridor. While this area has been creeping NW with successive model runs, it has been remaining  well to our south. 

So…. is it right? Will we actually see this incredibly sharp gradient of precip to none? 

That is the question. 

 

Let’s take a look at the 700mb RH values shown on these same models: 

 

 

 

As you can see, both models show a ton of moisture being thrown up over dome of arctic air. This type of set-up often leads to an area of precipitation much further north than shown on models. Whether or not this occurs is yet to be seen, but the possibility is certainly there for a large area of mainly light precipitation along and north of I-20.  The SREFs seem to be indicating this and the WPC has highlighted the area with a 30-40+% chance of 1″ or more of snowfall Tuesday night.

Personally, I expect to see a large area of 1-3″ of snow north of I-20, with higher amounts possible mainly in extreme NE GA. Time will tell and I will update again after the 0z runs tonight.