Raleigh Weather Discussion
After another mild day today, we will likely see rain move back in this evening and overnight and be around at least in an off and on fashion through tomorrow. There will be some cold air damming tomorrow, so it will likely be a wet and cool day with temperatures staying in the 40s.
The storm system should be out of here by Thursday with slightly above normal temperatures Thursday and Friday. A cold front will push through during the day Saturday and that is when the forecast becomes tricky.
The GFS has consistently shown the threat for some wintry precipitation in the area in the Saturday afternoon through Sunday morning time frame. Yesterday’s 18z run as well as its ensemble members and the 00z ensemble members were pretty bullish with cyclogenesis occurring close to the Carolina coast and a nice deformation band setting up over the Carolinas with significant snow. However, the 6z run is a bit more offshore with lesser precipitation now as well as many of the 6z GFS Ensemble members. The ECMWF and ECMWF ENS members have shown development well off shore for a few days in a row now which would mean little precip if any. The Canadian on the other hand shows a strong storm but further to the north. It is hard to say for sure but the 00z UKMET is still close to being an event, while the NOGAPS is a significant event.
The bottom line is that there is still significant uncertainty for this weekend. My guess is right now, we may see some light rain/snow Saturday afternoon and night, but I cannot go for a significant storm yet. These situations where waves develop along an arctic front are always very tricky, so I wouldn’t be shocked to see more significant model oscillations.
Cold weather will pour in for Sunday and Monday. Before we warm up for another cold frontal passage on Tuesday with more rain likely and cooler temperatures for mid to late next week.
National Extended Weather Discussion
IT looks like a moderate to strong –NAO combined with a neutral EPO and –PNA this period will mean cold weather for the interior West, Rockies, and Plains, with the Northeast varied, and the Southeast warmer than normal. Despite the –NAO the persistent –PNA means a trough in the Rockies will produce a ridge downstream over the Southeast. This has been a common theme this season, so I don’t have much reason to doubt it.
This will mean an active storm track from the Southern Plains into the Ohio Valley and mid-Atlantic. This is a pattern ripe for Miller B type storms with the potential for a snowy pattern for the Plains, Midwest, and Northeast. However for the Southeast, after the next 10-12 days, it will likely be a rainy pattern with less chance for wintry precipitation if the model forecasts are correct.