I've tended to find, as I've discussed on other occasions here, that the NAO really tends to implicate the frequency and intensity of Miller A cyclones/coastal low type winter storms in NC, which usually favor snow over the coastal plain, eastern, northwestern piedmont &/or mountains of NC, whereas for cold air damming events and these so-called "hybrid"/anafrontal storm types, the NAO is really not a huge player, if at all. Taking away the -NAO really tends to reduce the number of these coastal low setups around here but obviously doesn't
eradicate the potential for other winter storms.
Here again is the composite 500mb & MSLP patterns in NCEP Reanalysis for 184 Miller type A "days" and 205 type B winter storm "days" in NC, showing fairly clearly what large-scale pattern favors and tends to be associated with each storm type.
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When you really start to dig into the numbers and now look at the snowfall from these storm types & the hybrid class of winter storms you can see which parts of NC benefit the most from Miller A cyclones often found during -NAOs.
Raleigh & the I-95 corridor's bread & butter are indeed these Miller type A storms. Once you take those away however, the playing field changes significantly.
In fact if you were able to remove Miller type A storms from NC's snowfall climatology, Raleigh's long-term snowfall climo would actually be the same as Charlotte's!
Things are much different when you look at Charlotte however, which actually tends to perform better in comparison during Miller B & especially these Hybrid/Anafrontal type storms (which are usually coupled w/ big +PNAs) that really don't occur in conjunction w/ -NAOs at least anywhere near as frequently. Furthermore, the reason (as
@GaWx has noted ad nauseam) really don't see these significant -NAO correlations w/ snowfall in other areas of the southeastern US likely is because in those areas like GA, SC, AL, MS, etc you really just don't see intense Miller A cyclones all that frequently (w/ Jan 3-4 2018 & Mar 1993 being huge exceptions). This really makes sense because these areas of the deep south are further removed from the climatological position of the mid-latitude jet core and most favorable baroclinicity near the SE US coast in association w/ the Gulf Stream being adjacent to the relatively cooler SE US both of which aren't as conducive to intense coastal cyclones which again are significantly implicated by the -NAO. In a majority of cases where a Miller A winter storm occurs over NC these other areas of the SE US either see nothing or a preceding hybrid/anafrontal type winter storm during the earlier stages of the storm's overall life cycle.
Oth, if you progress further north into the mid-Atlantic and NE US, an overwhelming majority of their biggest winter storms come exclusively from coastal cyclones/Miller type A events. NC sits awkwardly in the middle of these 2 areas with one relying very, very heavily on the -NAO for large winter storms (NE US), whereas the other, the deep south, not so much.
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Based on the above information & research, I really think if you take coastal cyclone winter storm cases out of the equation, the NAO really doesn't matter that much to NC's winter storm climatology.
