Raleigh Weather Discussion
I really don’t have much new to add to what I have been writing all week. The next 6 days will see gradually warmer weather and dry weather. It still looks like we will be near or even a few degrees above 70 by Monday and Tuesday.
A cold front will approach the area later Tuesday and Wednesday with the timing of the frontal passage right now looking to be early Wednesday. If the front could pass Wednesday afternoon and evening there could be a better chance of rain and even a few storms, but a Wednesday morning passage would probably mean mostly some light rain. There will be a cool shot behind this but only knocking temperatures down to near normal.
We will quickly warm up again by late next week ahead of another, probably stronger cold front. The warm-up may not be as strong as the one coming this weekend and into early next week but we will likely be into the mid or upper 60s again by next weekend.
National Extended Weather Discussion
It appears that the best chance for any substantial cold in the next couple of weeks is going to be over the Rockies and perhaps the Plains beginning particularly around 12/8-10 and after. The pattern looks like to place a general trough in western Canada and into the NW and northern Rockies with a general ridge over the Southeast and eastern US and a general trough over the western US. While the NAO may be slightly negative in value, it does not look like we will see the classic –NAO setup of a Greenland or Iceland block and negative height anomalies underneath it. So it appears the general –AO and high latitude blocking setup is going to serve to dump cold air and a polar vortex into Canada and some of this cold will likely move into the Rockies but surges east through mid-December will likely be limited in scope, intensity, and duration.
The MJO has essentially weakened and become non-existent and this combined with the variability from cycle to cycle of the ensembles is leading to higher than normal uncertainty. So things could change quickly and the above pattern by no means is likely to lock in all winter. If anything this winter could be pretty volatile. Just think a week ago it looked like a cold pattern was about to lock in for December for the East just to show you how quickly things can change. So don’t give up winter lovers, it is still technically only November! So even if the warmer setup for the East is true, it could flip quickly in the 2nd half of December.