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Depending on your perspective…the good news is that this storm will be a blockbuster.  The bad news is that it looks to be busting the biggest blocks in VA rather than NC.

The track of the storm and upper-level closed low will ultimately determine who’s in the money (north) and who’s not (south).  There has been lots of shuffling hither and yon with the low track among the models and between run cycles over the last several days from extremes of a SC/GA track to a Jersey track.  Now though, as the upper-level energy that will spawn our storm has just this AM entered North American, we should expect the various models to converge on a consistent solution.  We see that happening to an extent, but there is still a lot of waffling going on from run to run.  Especially, in light of the fact that 50 miles difference in the track might mean the difference in 1″ vs. 6″ or rain vs. 2″.

What can be said with a high degree of certainty is that the storm will approach from the west, and as it nears the coast, it will rapidly intensify.  As it does, a relatively large deformation band with moderate to heavy snow will form on the storm’s west in the cold air.  It is in this deformation band that some places will get whacked with 1 to 2ft of snow and a howling wind (think Jan 2000 storm).  As it appears now, central VA stands the best bet for heavy snow.  The Euro has been consistently farther south with it’s low track for the past day or two vs. the American, GFS model.  And remember that the Euro generally beats the GFS in mid-range skill scores.  So while there is still time to hope for a continued trend south, it’s unlikely that there would be that much change to put us in the sweet spot in north central NC.

First guess for Raleigh…rain arrives on Tues, tapers off for a while as we get dry slotted on Wed AM, then rain begins again, mixes with and changes to snow Wed afternoon and we end up with a trace to an inch.  Snow totals slope up as you head north toward Roxboro where they stand a better chance for appreciable accumulating snow to 4-6″.

More tomorrow…

Let the hype begin!

Now that we’re talking about day 6 in the forecast, you’ll see the media outlets feel like they can utter the dreaded 4-letter S word.  The modeling on this one has been remarkably consistent for a couple of days now for feature at the 10-day range.  Of course, the exact track will ultimately determine precip type and how much of it.  This storm will come from the west and intensify at the coast.  Lots of details to figure out, so at this point it’s just something to factor into your Wednesday planning contingencies.  Your next question is probably…”could this be a ‘good’ snow?”  The answer is…yes, there is potential there for a several inch event.  That being said, there is the potential for the classic NC 35° rain.  And I’ll add on that there is also actually the potential that the storm track is suppressed so far south that this turns into a SC snow instead of NC.

One last thing…yesterday, I was reminded of the difficulty of getting it to snow in March in NC when I got into my truck that had been sitting in the sun all day…hot.  The sun angle is getting pretty high now, so you have to have a steady supply of fresh cold air to make the magic happen this late in the year.  And if it does happen, a lot of times the snow comes, is pretty, and  then is gone before you blink your eyes….which is probably a nice thing for a lot of people.

Oh and I forgot to talk about this weekend…yes, there may be a sprinkle or a flurry Sat PM.  Nothing to worry about for that one.  Save your grocery money for next Wednesday 😉

It’s a beautiful snow here in Raleigh as the big wet flakes are now piling up on everything but the roads.  And that will continue to be the situation until late this afternoon and evening when the real cold air arrives.  The enhanced precipitation rates over Wake Co. in particular have done an excellent job of dynamically cooling the air temp to just above freezing.  So, as long as it continues to snow at least moderately, the accumulating snow will win the battle over warm antecedent ground temps and the diffuse insolation thru the clouds.  This first wave of snow should taper off this afternoon and then the debate really becomes how much if any precip shows back up late afternoon and evening in association with the developing low off the coast.  The likely bet for now is that it’s nothing more that a couple of snow showers, but it’s a situation that needs to be watched, especially for NE NC toward Roanoke Rapids and Va. Beach.

For now, enjoy the snow!

There’s more disagreement on this weekend’s snow than there is in the U.S. Congress.  And also like Congress, there may no deal cut until the final hour.

But…the trend has been to form the storm closer to the coast and therefore produce more precip farther west.  We’ll probably see the precip begin as rain and transition over the snow.  The best bet for accumulation in Raleigh is 1-2″ and I could see 3 happening.  Higher precip amounts NW and west could result in more snow toward Rocky Mount and Roanoke Rapids, but the cold air will take longer to get there.  So, you would be fighting that battle to balance the two.  As ground temps are high and it’s currently a lovely 61 at RDU, accumulation will happen last (if at all) on the roads.

As I said last night, this could swing either way on a dime.  And it’s this type of situation that feeds the fire that meteorologists are roasted over.  Here’s to some BBQ!

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.