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I said earlier in the week that the weekend system would bring, at minimum, a good chance for a flurry, even as the extent of the coastal cyclogenesis was uncertain.  Well, here we are less than 48 hrs from the event and what I can tell you is…”well, there’s a good chance of a flurry and we don’t really have a good handle on the extent of the costal cyclogenesis.”  Hmm.

No need to bore you with the history of the evolution of the thinking from earlier in the week to now, but suffice it say, the trend of the models over the last couple runs has been to flip back to a stronger coastal storm.  So, i’m pretty confident the Triangle will see snow Saturday afternoon/evening.  Of course, the question is how much.  The trends favor at least a little accumulation.  But, you have to remember that ground temps are really warm, and it will be over 60 tomorrow.  That being said, we do have models coming in tonight with 4″ in Raleigh.  Ok, I shouldn’t have divulged that…calm down!

For now…let’s just say that we have a difficult forecast for Saturday.  And let me remind you all that cyclogenesis of any kind is one of the most vexing forecast headaches facing meteorologists.  But, East Coast cyclogenesis is particularly complicated and only maybe 90% understood.  It’s that 10% that still gets us in trouble.  Can you say January 2000?!?!  By no means am I say that’s going to happen, just this is a scenario where the margin of error is W – I – D – E.

More tomorrow…

In hindsight, the blizzard in the northeast on Saturday looks to be the opening zinger in an Ed Sullivan-like parade of acts for the Eastern US over the next week to ten days.

What is clear at this point is the first shot will come overnight Wed in the form of a moderate snow event for northern VA and DC thru Jersey, maybe up to Long Island.  For NC, we’ll see more rain…a 1/2″ in the Triangle to an 1″+ south to ILM late tonight into Wed.

Then, things get murky with the potential for coastal cyclogenesis late Saturday into Sunday.  The numerical guidance is are all over the place to the range of possibilities.  It does look like there’s a decent chance that Raleigh could at least see a flurry, but as to ‘weather’ or not this evolves into a major East Coast storm or not…  It will be something to watch over the next couple of days.  Depending on how this evolves it could end up being an eastern NC special.  Unfortunately, the Euro is not in this camp.

Then, mid next week,  there maybe another wave that evolves into an East Coast storm…but probably north of NC.

So, it’s an active pattern.  Enjoy the snow? and rumors of snow!

I’m just in from working offline and a little astonished to find WCPSS has a 3-hr delay tomorrow.  Indulge me here…

Once upon a time, let’s say back in 1977, a 4-year old boy lived in far away land…let’s say, Kalamazoo, Michigan.  He was an active, vibrant youngster who loved to run and play trucks, but would also give the biggest hugs.  One day at preschool, the children had just come in from an exhausting stint on the playground (with special fun on those dangerous monkey bars) to settle down at the tables for a tasty spring snack of grapes and cheese.  Our little friend loved cheese, and loved grapes even more.  So, he gobbled the snacks all down.  Except, wait.  Something was wrong.  One of the grapes was stuck in throat!  His teacher ran over, popped him on the back, and seconds later a half-chewed grape lay strewn on the table.  The little guy perked up, asked for seconds and was back on the playground hanging upside down from the monkey bars a half hour later.  But news of the horrible incident spread, and from that day forward, all grapes in preschool were to be cut in half…

Ok, so I’m being silly, and I’m not good with odds…but I would say the odds of this event causing accidents are really, really, really small.  So much so that I could write a similar fable as above about a little boy who traversed out into the scary elements only to find the one icy patch in the county.

All this to say that there could be an icy spot on a bridge or two….maybe…but to upheave 150,000 students plus teachers seems ultra cautious.  I’m expecting the precip to be spotty, short-lived and light…no more than a hundredth of an inch or two.  Most locations will not see more than a trace of precip.  Sigh.  But exciting for the kids to sleep in later tomorrow.

Final rant, it’s funny to me that they delayed schools 3 hrs when the NWS official advisory expires at 9am.  Whatever, I guess it’s easy to criticize when you’re not in charge.

All of the snow is over.  And a lot of the sleet is probably done (especially south of Raleigh), although it could mix in from time to time, especially at the onset of the next round of precip, set to arrive in Raleigh by 2:30.  Indicators now show the potential for the remainder of this event to take the form of a significant ice storm where glazing could accumulate to 1/4″.  Temps are solidly locked into the mid 20s and will remain there.  This will make for easy accrual of ice on most everything, including untreated roads.  If we start to  approach 1/4″, then we’ll begin to see problems with trees coming down and power outages.  If we see more sleet at the beginning and less freezing rain, we may only realize a little more than .1″ of ice, which is better for the power situation, but worse for the roads.  This is more likely from Raleigh and north.  But eventually, everyone goes to freezing rain and gets some glaze.  Watching…

There is a forerunner band of snow and sleet that will be pushing thru the Triangle earlier than advertised.  In fact, this band wasn’t even picked up on by the latest runs of the NAM this AM…so consider it a bonus! It’s moving quickly from west to east.  It should arrive in Raleigh about 10:30 or so.  It will be mostly snow with maybe some sleet and should be enough to lay down a dusting.  But it will be short-lived lasting no more than 30 mins.  Then, the coverage will be rather spotty until the main batch of precip arrives later in the afternoon.  Just wanted you to have heads up on this so as not to panic, thinking snow-mageddon was imminent ;-).

The 0Z runs are in and there’s no question that they are wetter.  Some up and down is expected, but we have two runs with a little more moisture depicted.  It will be quite cold at the surface thru this event, so the precip will all be frozen or freezing in Raleigh.  I’m thinking that the precip doesn’t begin until 2pm in Raleigh, probably as a brief period of snow then quickly mixing with and changing to sleet for the majority of the event.  Later in the afternoon to early evening, we’ll probably see a change over to freezing rain and drizzle for a light glaze overtop of the snow/sleet accumulation.  How much accumulation?  Since most of the accumulation looks to be sleet and since the nature of the precip will be showery, I’d be pleasantly surprised for more than 1/2″ in Raleigh.  Plus, you’ll get a little glaze overtop.  I think the media outlets have done a good job in emphasizing how little it will take on untreated roads for them to become very slick. The past several days have, obviously, been very cold and tonight we’ll dip to the lower 20s.  All this to say that, ice on untreated roads in your subdivision or cul de sac could make for fun sledding if we can get a thin layer down.

As I said earlier this afternoon, we’ll see how the precip shield breaks out to the west of NC overnight.  And we have one more full model cycle to look at late tomorrow morning.  For now, it looks like areas just east of Raleigh, north and east to Elizabeth City and the Tidewater of VA stand the best chance of significant ice issues.

More tomorrow AM.

Not that one should waffle back and forth with each model run, but as you get closer to an event, presumably model guidance should improve.  After several cycles of trending drier, the 18Z models have come back around wetter, owing to more precip from the low deepening as it exits the coast.  Under the the latest runs, it would be snow at the onset, to sleet, to a freezing rain glaze on top.  Could be, but I’m not ready to fall for this tease yet.  For now, we’ll just wait for more data to come in and watch the system as it begins to organize tonight over the TN Valley.  Tonight’s model runs should be more reliable with fresh data included in their initializations.  We’ll see if we have reversed the trend back a little wetter or not.  Any way you slice this, it will not be a heavy event.  The question is…will this be just a nuisance or create minor travel headaches.  More tonight.

Moisture really looks starved for tomorrow.  So, for the second dance in a row, it looks like the guest of honor won’t show.  For a good portion of central NC, I think this will play out as a couple of snow and sleet showers that will in some places accumulate enough for a dusting to a half inch, and other places not even that.  Actually the locations that will stand the best chance of getting and inch or so look to be from Rocky Mount northeastward.  It’s ashamed to waste all this perfectly great cold air…alas, it is NC.

Next week we thaw out with the possibility of highs flirting with 70, before the cold returns.  And it could be another significant cold spell thru the first half of Feb.  Perhaps more chances for the elusive snow then.