Looks like the Pack victory was a good call! Now onto the snow to complete the “snow-pack”!
Precip should begin arriving not too long after lunch. With dry air rushing in on the back of a stiff NE breeze, any rain and sleet should quickly change over to snow. As we approach rush hour, the intensity of the snow should pick up and we should be in for a beautiful snow thru the evening.
Let’s say 3-5″ for Wake county. Again, the real winners look to be east where it should be 8+. Back towards Greensboro and Charlotte look for more like 1-2″
Looking ahead, Saturday morning lows will be near 20. That hard freeze will make for bad traveling on whatever is on the roads.
I thought I’d push a quick post 1) as another test that my website issues are resolved, and 2) because I won’t get to update until after the Wolfpack beats Duke in the late 9pm game tonight!
The models continue to come in, in support of a significant winter storm in central and especially, eastern NC. The short term ensembles are impressive as well.
I still like the axis of heaviest snow to line up from Raleigh and extending northeastward toward Norfolk. I feel more comfortable with the idea of something closer to 4 or 5″ in Raleigh with higher totals in that Rocky Mount to Edenton zone nearing 8″.
I’m sorry to not have posted until now. There were technical problems with the website. (perhaps I was hacked by the Europeans so I couldn’t poo poo their model
While certainly it is too early to declare an American model victory, what can be said is that the deterministic Euro and its ensembles have steadily ticked up from 0 to 3+” for central and eastern NC over the last 4 runs. It should be reiterated that the Euro skill scores are statistically superior over all global models, but as they say… you can’t win ’em all. That appears to be what’s going on here.
Comparison of Euro snow maps from yesterday 12Z to early this AM at 6Z
Snow looks likely for a good swath of NC tomorrow thru early Friday AM. The NAM, while maybe overdone, has displayed remarkable run-to-run consistency. It is insistent on strong frontogenetic forcing which would drive heavy precip rates. Those heavy precip rates will be key in overcoming warm antecedent ground temps.
A concern with all this strong forcing is how far north the warm nose will extend. The warm nose (elevated layer of temps > 0° C) will turn snow over to sleet and reduce totals in those areas. Right now it looks like the warm nose will make it no farther north than central to southern Wake county.
I’d like to digest the complete set of 12Z model runs before passing judgment. And, of course there’s a problem with the GFS coming in this cycle. At this point it’s about an hour late.
The skinny… Precip starts late tomorrow AM as rain or rain/snow mix. Changes to snow for a good chunk of NC. Mixes with and changes to sleet in the south. Storm totals highest from Raleigh north and east. Raleigh is probably 2-4″, up to 6-8″ toward Rocky Mount and to Edenton.
Raleigh has escaped the storm with the best possible outcome…a beautiful 4-7″ snow and temps hovering just above freezing to avoid any damaging ice build up.
But wait, there’s more…
It looks like there will be another round of snow and sleet early tomorrow AM as another shortwave rounds the trough. The latest trends in the modeling indicate there could be another burst of heavy precip for at least a couple hours. Surface temps will again be hovering close to freezing, but the precipitation rates should be high enough to achieve more accumulation. This doesn’t look to be the case for everyone in NC, but under this band should be a thumping of 1-2″ …possibly isolated cases of 3 or 4″. Right now the Triangle looks to be included in this next round. And this would be just in time for tomorrow’s morning commute. More winter fun!
Tomorrow evening clearing will following and temps will drop to the mid 20’s for lows. Refreezing will be a major issue on Tuesday morning.
As much as everyone wants to hear the latest… the latest is that what I outlined yesterday still looks good to me tonight.
I can see concerns for bust potential above and below my current forecast. My thoughts on Wake Co. follow, but really they are applicable to the wider region…
bust big?… there will be a period of heavy snow after the initial onset of precip which quickly cycles thru rain to sleet to snow. some models say there could be as much as 6-8″ in that initial hit. so, you’d have that and then sleet and then frz rain.
bust small?… fears of the warm tongue penetrating earlier and more pronounced would limit the initial accumulation of snow and changeover precip to sleet and freezing rain much more quickly.
I’m going in the middle on this and holding firm to my forecast from yesterday. The action starts overnight with snow beginning in earnest between 2 and 3am. I’ll nowcast early morning with an update for how that tricky transition zone looks.
It’s been many, many years since NC has experienced a winter snow of this magnitude this early in December. This storm promises to make it a December to remember.
As has been widely advertised, there are going to be heavy snows to the west, rain to the south and east and a battle zone that should line up fairly close to a line from Raleigh to Charlotte where the forecast is super complicated and the weather super messy. I can hear the bemoaning of the infamous “line” as I type. There are some interesting numerical modeling disagreements ongoing behind the scenes that hopefully will be resolved soon, but in the larger picture here are a couple of key points:
There will be a lot of moisture available for this system. Liquid equivalents will run about 2″ for most along and south of the Triangle and Triad with amounts tapering to an inch along the Virginia border.
Heavy snows of 12 to 20″ will be common in places like Greensboro, Hickory, Boone, Asheville where most of the moisture comes in the form of snow with little mixing.
The zone to the south and east, in places like Burlington, Chapel Hill, Salisbury and Concord, should probably expected half snow, half sleet and a little freezing rain.
The next zone to the south and east has Durham and Raleigh and Charlotte. I expect a mixed bag of it all…something like 3-6″, 1-2″ of sleet and 1/4 of freezing rain. Remember that west and north in these zones you are more likely to skew to snow. For instance, Durham may get 6″, Raleigh may only get 3 or 4″.
Remember that whatever snow you get will be compacted by any sleet falling on top of it. So, you could measure 6″ pre-sleet and shrivel down to only 3″ afterwards.
IMPORTANT: The impacts of this event will be high and widespread no matter what form the frozen stuff on the ground is. And after you get a couple inches, it’s really all the same in terms of impacts. It just takes longer to go away with more of it there when it’s over.
Something to watch will be the extent of the freezing rain. If the warm nose penetrates farther north and west and deeper than is currently thought, significant ice accrual could become a real problem.
Timing: this looks to arrive from south to north overnight tomorrow. For Raleigh, perhaps in the 1-3am timeframe.
As always, stay tuned as we monitor the latest trends and I will update as necessary.
Details need to be ironed out, but what it clear is that an early season winter storm is on tap for much of NC this weekend.
I don’t want to get into specifics this early… we have plenty of time for backyard forecasting later. At this point, let’s say that from Wake Co. N and W this will be a high impact event with significant snow, sleet and freezing rain beginning at late night Sat into Sun and continuing thru Mon. Especially from Greensboro west, the snow totals will be historic for this early in the season.
Of course, we still have three days to go, but as it is now… the model guidance is converging on a storm to remember. Start making alternate plans for Sun, Mon and Tues of next week.
A quick post to say, yes… there is the potential for a major winter storm in many parts of NC, VA and upstate SC this weekend.
Of course, all that potential doesn’t mean anything unless it’s in your back yard. It’s waaaaay too early to say anything definite. Be alert for the possibility of significant issues, especially north and west of Raleigh. At this point, we can say that there is the potential for higher precip totals (liquid, frozen or refrozen).
We will monitor the evolution of this system for impacts Saturday night thru Monday. This will be a fun week of forecasting!
The main rain shield from Michael is just arriving in Raleigh. The heaviest axis of rain looks to setup west of the Triangle where several inches are likely while totals near Raleigh are likely to be more on the order of 2″.
Our main threat appears to be from a period gusty winds in the 5:30-7:30pm timeframe after most of the rain has passed. On the back side of the circulation will be a burst of winds that could catch everyone off guard, thinking the storm has passed. The higher resolution models indicate that higher momentum air above the surface should get mixed down to near the surface making for a short period of of straight-line winds similar to a derecho event. 10m winds are indicated in the 60-80mph range. If this pans out, we can expect lots of trees down following the soaking rains, plus associated power outages.
Again, this looks to move from west to east thru the Triangle just after commute time. Stay alert.
Michael is gaining strength offshore of the Yucatan Peninsula tonight. If not for stiff westerly wind sheer, Michael would have the potential to strengthen rapidly. As it appears now, Michael should have to deal with significant wind shear throughout its evolution. Hopefully, that will limit its intensity. There is uncertainty to the extent of that influence. So, while I would expect Michael to be a borderline 2/3 storm at landfall…it’s certainty possible for it only to be a minimal hurricane or, as some outlier models suggest, a cat 4. I’ll remind you that track forecast has much higher skill than intensity forecasts.
So what does it matter for NC?
Landfall should be along the Florida panhandle. Then, the track is likely to be just inland from the coast all the way up through SC and NC before exiting the Outer Banks. Again, the exact location of the center of Michael isn’t so important except that a cat 3 moving inland fast (even as far south as Florida) will dictate where the gustiest of winds will be.
And speaking of fast-moving… it looks like this may be a saving grace with Michael. Still, we’ll expect gusty, perhaps damaging, winds in eastern NC along with 3-5″ of unwelcome rain.
Lots of time to figure it all out before impacts in the Thursday timeframe. Of course, there’s still some discrepancy in the thinking on that as well. Stay tuned.
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