It appears the timing of the cloud cover and possible rain will keep us from getting too warm today. Originally I had envisioned mid 60s today, but it looks like now upper 50s to low 60s is the best bet across the Triangle. Rain should hold off until after dark, so it could be a great day to enjoy being outside. A rarity this winter.
Cooler weather does look to return next week with highs in the 40s to low 50s and lows in the 20s common next week. The models are struggling with the timing of individual systems over the next 1-2 weeks as we see another large Greenland Block (west-based –NAO) set up, helping to create a strong 500mb low over southern Quebec and northern New England. This has been a common feature this cold season. At the same time, the models are showing an amplifying ridge in the west and cross-polar flow beginning. This is a classic sign of an impending arctic outbreak. It is also synoptically a pretty good setup for southeast US winter storms.
The models have oscillated in showing threats between 1/6-1/14 and possibly beyond as well. The 00z Canadian and yesterday’s 12z ECMWF insinuated the possibility of some snow or a wintry mix by Thursday. The 00z ECMWF did back off this though. The 00z GFS did not show an event then, but a few of it’s ensemble members did. A potentially bigger event could come around 1/10 to 1/11 as we see a classic setup of a strong Newfoundland Low, west-based –NAO Greenland Block, ridging in western Canada, and a s/w moving across the southern US. If these factors do setup, there is a good chance of a significant winter storm in this time frame. Of course this is 10 days out so many things can change.
Beyond this, the models are unanimously showing very strong high pressure building in western Canada (1050-1070mb high), that looks poised to move into the Rockies and Plains around 1/13-1/15. This could bring the coldest air mass of the winter season to many parts of the US for mid-January. The Ensembles continue to show strong blocking near the Davis Strait even on day 16 (1/17) so I don’t see an end in sight for the cold pattern.