Wet Pattern Emerging: After the soaking we received late last week, yet another potent system will spread rain across the Upstate, NE Georgia and Western NC on Thursday. Much of this has to do with the emergence of an active sub-tropical jet stream from the southern pacific transporting moisture in our direction. This sub-tropical jet was asleep for much of the last year to year and a half!
Towns will likely soak up between 0.5" and 1" of rain tomorrow. As for timing, it looks as if the best chance for rain will be mid-morning through the afternoon.
High Winds & Friday Mountain Snow: A High Wind Watch is currently in effect for all of Western NC until Saturday at 1:00PM. Expect sustained winds of 10-20mph with gusts to 30+mph.
Also, once a strong, cold front passes through on Thursday night, the high elevations in Western NC will switch over from light rain to some off/on heavy snow showers. Due to very cold 5,000ft temperatures whipping into the Mountains, snow bands will be enhanced on Friday, especially in the morning. It looks as if totals between 2-4" and possibly close to 5" will fall along the ridge tops. I'm anticipating the National Weather Service will either issue a Winter Storm Warning or Winter Weather Advisory for Graham, Swain, Haywood, Madison, Yancey and Mitchell counties.
Weekend Travel Plans: You will be good to go if you have plans to hit the road or the air this weekend. A clear, blue sky and sunshine will mean dry roads and zero travel delays.
Next System Around Christmas: The bottom line on the next storm system moving our way is that there are still many questions on when exactly we will be impacted. There are far less questions on what sort of precipitation will move our way.
Rain can be expected for Upstate and NE Georgia towns. It is worth noting, however, that there could be a very shallow layer of cold air funneling down the eastern side of the Appalachians. We often refer to this as cold-air-damming or a wedge. This shallow, cold air mass will undercut a warmer air mass fully loaded with moisture moving in our direction. There is a slim chance that portions of our eastern North Carolina counties such as Rutherford, Polk, Henderson, McDowell, Buncombe, Mitchell, Yancey COULD see a brief period of freezing rain at some point next week. Let's be honest... nobody wants to deal with freezing rain capable of knocking our power next week. The good news: this situation likely will not happen, but it is a possibility worth keeping an eye on due to the placement of features (possible cold, high pressure in the northeast) on the map next week.
Also, this shallow cold air setup holds ONLY a slim chance of freezing rain. Due to the track of the low pressure system and the lack of cold air in the middle and upper levels in advance of this system, this system offers no chance at snow for anyone except for a northwest flow snow event in the high elevations of NC on the back-end/post-frontal.
Late Fall Perception & Some Post-Christmas Chill: First of all, keeping in mind that late fall encompasses much of December, I find it interesting that the perception of how cold we "should be" in late fall has changed for so many people after the Christmas snowstorm of 2010 and the cold snap that preceded that storm system.
The bottom line is... our climate, especially in the Upstate of SC, lends itself to many more warm stretches than cold stretches in the late portion of fall and this has always been the case. Obviously winter begins on Friday the 21st, so we'll see where things go from there. We will deal with at least a temporary cold snap around the 27 through the 29th of December (after the Christmas system moves through). Again, this cold will likely not be with us for more than a couple of days. I can say I am 100% certain that this winter will not be exactly like the last winter (which was non-existent).
The reasons: Along with the absence of La Nina, especially with the emergence of a -SOI (active subtropical jet), I can tell you that there are some obvious signs southwest of us, north of us and northeast of us... all pointing to big differences between where we are headed in winter '12-'13 and the non-winter of '11-'12 (last year). (1) The suddenly active subtropical jet. (2) A strong Greenland block/ridge scheduled to set up shop by this weekend and hang around for at least a week causing some temporary cold after Christmas. This block allows for a more favorable cold pattern in the east. To compare, a Greenland block/ridge never presented itself last winter. Also, (3) the arctic oscillation is negative and is forecast to stay that way for a bit which means reinforcing shots of cold are more likely to move south from the northern latitudes. You guessed it... a -AO was never present for any lengthy periods last winter.
Most importantly though, a fast moving pacific jet stream (south of Alaska) does look very similar to what we experienced last year (so far anyway). Due to this pacific influence, I believe lasting cold snaps longer than 3-4 days will likely not happen much (if at all) this winter. Still, a re-emerging sub-tropical jet stream means we should have a relatively wet pattern through mid-January (at least). It goes without saying, but moisture is one of the ingredients needed for winter weather around here and all it takes is good timing with cold air JUST ONCE to cash in on some snow.
Trust me, I have seen many winters in MS, TN, GA and SC where there was more warm than cold, but there were also some properly timed systems with cold and moisture coming together which ultimately led to some heavy snow.
A winter around here doesn't need to hold more cold than warm to produce snow. We live in the southeast and 75% of the time we will have more warm periods than cold periods during winter. The key, though, is to realize that we do need an active, wetter pattern (needs to be wetter than last year) to produce more chances of seeing widespread snow around here.