Good Monday evening to everyone…interesting times in the weather world as some changes already underway could lead to interesting times ahead for forecasters…
For us, we look at pattern recognition when it comes to predicting winter weather several days out. Around New Years we started getting indications that a colder pattern was coming to the Eastern US after dealing with such an abnormally warm December. The dynamic storm system that produced heavy mountain snow last Monday was the first piece to flip the pattern.
Once that occurred we began to look at the teleconnections to see if we could evolve into a favorable pattern for snow outside of the mountains in North Carolina.
The first teleconnection that is becoming favorable is the anticipated -NAO (a.k.a. The Greenland Block) for late this weekend and early next week…
In conjunction with the -NAO is the positive phase of the Pacific North American Oscillation (PNA). That has already verified and will peak as we get to this weekend…
LATE WEEK SYNOPTICS, SNOW CHANCES?
The weather setup at the jet stream level already indicates the influences of the -NAO, +PNA setup at play.
A shortwave will move through the Southeast on Thursday and then off the Carolina Coastline on Friday, there will be little precipitation associated with it however it will bring in a reinforcement of cold air into the Western Carolinas. Hot on the heels is a second shortwave moving into the Northern Plains. Due to the increasing ridge across Western North America, the second shortwave will be allowed to dig and take a more southern route…
Once we get to Saturday morning you see the continued PNA ridge signature, meanwhile the shortwave digs down to the Lower Mississippi River Valley. This could very well spawn a surface low pressure across the Southeast on Saturday. With cold air in place some wintery precipitation is possible.
By Sunday morning, the second shortwave will be exiting off the Southeast coastline. Due to the building -NAO, there will be no lifting of this feature up the coastline… The PNA ridge re-loads early next week possibly repeating things again outside the current 7-Day Forecast…
Guidance today has really trended toward winter weather possibilities for this weekend. It’s way too early to know IF or HOW MUCH winter precip is expected.
Here are some early probabilities for snowfall across the Southeast…
Stay tuned as we will update the weekend forecast throughout this week…