“Wintry Weather Potential Next Weekend”
First, I apologize for the lack of posts the last 3 weeks. It appears life has settled down a bit and so I think I will be able to post regular updates again starting Monday.
The reason for this post is that our very cold march appears to be locked in and will continue through most of the rest of the month potentially, and a severe –NAO/-AO may help create a very late season winter weather threat across parts of the Southeast/mid-Atlantic next weekend.
The ECMWF for 2 runs in a row has shown a stripe of accumulating snow across part of NC/SC/TN/VA/GA. The 12z GFS/GGEM have a similar look but are a bit suppressed but threatening looking aloft much like the ECMWF. We will wait and see what the 12z ECMWF shows.
The synoptic setup is that a strong –NAO will be driven by a strong polar low over SE Canada, a blocking ridge north of this. This will force a s/w rotating in from the Gulf of Alaska and it will dig SW creating a SW flow aloft and the possibility of one or more low pressure areas to develop in the Gulf or off the Southeast US coast. It looks like it will be cold enough aloft for snow, but since it will be late March, boundary layer temperatures will likely be a concern. Snows after mid-March are very rare across the Southeast so the odds are against this but the synoptic pattern is very anomalous so if a setup were to cause one to form this would be it.
I will have much more on this Monday and perhaps an update tomorrow if something significant happens.