Earlier today we talked about the weather here in the near term but everybody now wants to know…will the weather be nice for the Christmas Holiday?
Well, here’s our latest thinking…
Computer models have come into better agreement over the past 24 hours in regards to the next storm system to pass through the Southeast US. A frontal boundary and low pressure will be sliding through the Southland on Friday and Saturday and nearing the east coast by first thing Sunday morning. Behind the front is our next invasion of cold arctic origin air.
The good news is that our frontal passage has been accelerated on the models to where most of Christmas Eve and Christmas Day should be fairly tranquil but turning colder. The close proximity of the front may allow for a few fleeting showers on Christmas Eve morning but it should be dry for most with high’s getting back up into the 50’s one last time.
However quickly invading over the western slopes of the Appalachians will be colder air, so it looks like Santa may get a little assistance coming in on northwest winds on Christmas Eve night. Everyone should be at or below the freezing mark when its time to open gifts first thing Christmas morning.
Christmas Day right now looks to be mostly sunny but breezy and cold with high’s getting only into the lower 40’s…a big difference from the 50’s and 60’s that will be experienced earlier in the holiday weekend. If you are going to the mountains for Christmas Day, a few snow flurries are possible as well with 30’s for high’s…so without a doubt it will feel like the holiday season both in the Western Carolinas.
This return of the cold can be attributed to another bout of ridging in Western North America. Instead of a full latitude ridge we have more of a blocking high in the northern latitudes that will dislodge another piece of very cold arctic air into the Southern Canada and the United States for the last week of 2017.
As you can see on the 500mb flow image we have the northern stream delivering cold air but we’ll also have a split flow from the Pacific loaded with pieces of upper level energy that will traverse eastward. We feel that another active weather pattern could load up for the final days of the calendar year. This is something that will have to be closely monitored for many sections of the country east of the Rockies.
This new invasion of cold is going to send our temperatures back to levels at or below late December norms. Here’s just a sample of the ensemble data for a few reporting stations in the coverage area.