ILMRoss

It took longer than I was hoping. But finally some flakes mixing in around historic oakwood in Raleigh

Ok, think I see what’s up. The radar beam goes upward as it goes further from the site- by the time the beam is reaching the NC Piedmont, its 3-4K feet in the air, where everything is still snow. Any changeover, which is what lower CC values will pick up, is below the beam

Which radar are you using?

Actually, CC will still easily pick out a rain snow line. It’s very useful in any winter situation, no matter the p-type

I think the r/s line won’t do a traditional steady march and will instead collapse and flip entire counties very quickly. It’s close... there’s a r/s mPING around Clayton of all places... anybody around there that can confirm?

Yeah honestly at this stage the dye has been cast and I don’t know how much more further knowledge can be massaged out of guidance. At this point, we’re comparing obs. Grit that’s a pretty brutal forecast. I’m a little more optimistic, I thought I would of learned my lesson by now!

why are people scared of the nam? I thought it looked fine.

sounds like the easterlies kept the beaches a little chilly! really hoping yall in SENC get a share of the action, always cute to see my parents send me winter pics from wilmington proper. you're on the edge in topsail but i wouldn't be surprised if you get a brief burst of some token flakes down there

we're gambling here- getting a couple of hours of rad cooling would be killer, but the flipside is that if clouds roll in before sundown, it keeps those higher temperatures nestled in a little longer.

My "yardstick" for quick hitters is January 2011, where Wilmington got about 4 inches in 3 hours. Hampstead, a little town about 10 miles north, got 9 inches. We basically sat on a frontogenesis band that overperformed. not a complete analogy, it was ultra cold that week and we started that event at like 27 degrees. I personally think that someone in a line between henderson and edenton could wind up with 8+ inches, but that changeover needs to be fast and swift for that to happen, and that's an extreme call.

i know that we're having fun piling onto WRAL but this blow their conservatism out of the water. wow.

Don't think it's a heat island, think it has to do more with perception of time while looking at radar (watched pot never boils, longest minute is a microwave minute etc...) I also think the transition line can and does slow down, but i think it has more to do with Raleigh's geographic positioning to where storms typically form off the coast- the gulf stream really dictates where these cyclones form and often they form in the perfect position for Raleigh to be flirting with that r/s line more than usual.

Alright, glad the qpf picture got cleared up. i think there's more frontier to to figure out- how the cycle evolves. (i'm going to say cyclogenesis some here which basically means the formation of low pressure) Guidance has a pretty interesting method of cyclogenesis- we don't get this that often to it's hard to say this definitively, but it appears we go lee cyclogenesis against the apps before a low forms off the coast? I'll pull a pressure field from an arbitrary model: We got two low pressure centers- one off the coast (as expected) but another floating around northern South Carolina. I think that this is doing two things: -enhancing precip in the western piedmont and -delaying the changeover in the eastern piedmont. how this feature is modeled is something i'm keeping an eye on. i have *no idea* how this will evolve because we simply don't see setups like this very often and i don't have a sleeve for this in my mental rolodex. but, i think that if the coastal develops more quickly, surface winds will have a more northerly component and expedite cold air advection. this would mean less precip i think for, say, davidson.

It's not often you see the GFS/GEFS body the NAM like this in the short term; but just goes to show, just because a time frame is a model's "wheelhouse" doesn't mean its necessarily correct

i don't think there's going to be a very pronounced dry slot and if there is it will be a luck of the draw kinda thing, i wouldn't fret too much over it