Raleigh Weather Discussion
The big story over the next few days will be an anomalous storm forecast to develop off the NE NC/SE Va coast Tuesday night and into early Wednesday. As of now it looks like everything is going to come together further north over the mid-Atlantic and not bring a round of significant wintry weather to North Carolina or points further south, although the NC mountains, (west-facing slopes) will see snow.
As an upper level system will cut off from the jet stream and drop into the Ohio Valley and then to North Carolina. As this happens a primary low moving into the Virginia/NC will weaken and a new strong low will form east of the Va Capes. As this happens, cold air associated with the upper level trough will overwhelm the storm from west to east and most of Va will turn to snow Tuesday night and a significant snowstorm is possible from Virginia to Maryland to Dc to the lower Delmarva, with potentially up to a foot or foot and a half in some areas where a strong slow moving deformation band sets up. Unfortunately for snow lovers here in NC, it appears that will be north of the state. There is the chance that areas in north-central to NE NC could get in on the southern part of this band as the rain change to snow Wednesday. However as of now, I would say any chance of accumulating snow will be right along the Va border with the Triangle likely seeing some snow flurries/showers with no accumulation.
As this storm moves out we see more typical early March weather replace it with dry weather and highs in the 50s and 60s and lows in the 30s. In fact Sunday is looking spectacular with sunny skies and highs well into the 60s. A new front could bring some rain by Monday/Tuesday.
National Extended Weather Discussion
In general blocking looks to continue with moderate to strong negative values of the AO and NAO expected in the coming couple of weeks. The EPO also looks to stay negative which is another cold signal. However, the PNA is forecast to go solidly negative which means a trough could go into the West or Southwest and a ridge is possible over the southern tier of the US. In fact, I expect generally colder than normal temperatures across a good deal of the US especially the northern tier, while Texas and the southern tier of the US warm above normal. If the ECMWF Ensemble is correct the East coast may not see extended warmth and in general it looks like March will end up a cooler than normal month for many as there are no signs yet, of a big, extended early spring warm-up.