And the Fun Begins!

The American models throw a damper on the party this evening.

At this point, they may be the outliers… in contrast, to the Canadian that came in on point for the storm as advertised. As of this writing, I’m not inclined to change any of my general scenario… yet.

Several days ago, we talked about the possibility for Raleigh to miss this as the storm could skew to the east. Maybe that can happen with this? We’ll wait for any pivots until all of tonight’s runs come in; but, more importantly, tomorrow’s midday runs of the 12Z suite. Those will show us know if this is a blip vs. a trend.

For now, let’s reiterate the axis of heaviest snow, with a tweak to pull the west-most point of Albemarle to change to Pittsboro. This becomes the west-most point of the favored axis, continuing on to Norfolk.

Anyway you look at it, Scotland Neck to Norfolk will have the highest totals, 5-10″ there. Then from Scotland Neck back to Pittsboro, totals should range from 3-6″.

Updates tomorrow!

NC Winter Storm on Track

A quick update to confirm that we’re still on track for a moderate to possibly heavy winter storm, particularly in eastern NC.

As the arctic front enters NC on Thursday, rain will begin to changeover to sleet and snow as the cold air invades into Thursday evening and overnight. The front will serve as a focusing mechanism for waves of low pressure to ride from SW to NE along the Southeast Coast.

There are still plenty of details to be ironed out, but 3 days out, the models are converging on a consensus for an axis of heaviest snow lining up from Albemarle to Raleigh to Norfolk. Immediately, southeast of this line there looks to be the axis of heavy sleet.

Behind the storm it will be very cold. We’ll be dealing with whatever falls on the ground for a while after the storm is long gone.

I’ll have a more complete analysis late tonight.

Watching One More Weekend Winter Weather Whirlwind…

As today’s storm winds down for us in NC, we can look back and say that it came and went pretty well according to plan.

Note: there is the possibility of a snow shower or two rotating thru Wake Co. near the upper level low in the 11pm to 1am timeframe this evening (Sun, 16 Jan). Nothing to worry about with respect to significant accumulation, just an opportunity to see more of the flakes that many wished they had gotten earlier in the day.

Looking ahead, we’ll have a relatively chilly week, but with moderating temps each day ahead of an Arctic front which arrives Thursday accompanied by rain showers. Then, the uncertainty begins as to the possibility of a coastal storm, which is now being alluded to in the long range models for next weekend.

The numeric guidance at this point depicts a different scenario than the setup for today’s storm. This setup would be more promising for a real snowstorm vs ice. It would be a coastal storm. If fact, one of the possibilities is that Raleigh could miss out by being on the western edge of the precip, while the coastal plain hits the sweet spot.

Again, waaaaaay too early for anything except dreaming. However, I will say that pattern thru the end of the month looks to be one of the most promising in a couple of years, if you are a winter weather lover. It will average well below normal for temps. We just have to get the timing right with the arrival of the moisture!

‘Ice’- ometric

No real changes this evening to the aforementioned thinking as to evolution of the impending winter storm

Best estimation for Raleigh metro is that we begin close to 7am on Sunday morning with some light snow. The snow will quickly change to sleet, with snow/sleet accumulations of only a coating up to an inch. The snow/sleet should quickly change over to freezing rain. Look for the warm air intrusion from the coastal front to push Raleigh above freezing between 12-2pm. This will obviously end any additional accrual of freezing rain, however dangerous travel conditions will persist with the snow/sleet/ice that remain on the roads.

Estimates in Raleigh proper are for a coating to as much as an inch of snow/sleet. On top of that, expect .1 to .2″ of ice accrual. The farther west you are, the higher the totals of both snow/sleet and ice. And since Wake county will be the transition zone, impacts could range from significant (west) to ‘meh’ (east).

I’ll update with any new information on Saturday

Now, Now Kids… Let’s Play ICE

We are now entering the “short term modeling window”. To this point, we’ve been using large-scale models for general macroscale storm guidance. There is now general consensus on the evolution of the storm such that, the track of the surface low (and coastal front with its warm push intrusion) probably won’t differ by more than 20 to 50 miles. Those 20-50 miles will be crucial for those on the eastern edge battle front, which will be near Wake County.

Let’s back up to clarify… barring any crazy last minute monkey-wrenches, the outline from last night holds. In Raleigh, we should see snow begin 4-6am Sunday morning. This will be short-lived. Expect the snow to change to sleet quickly. I expect the sleet to be short-lived as well.

The snow and sleet should lay down coverage from a light coating to an inch or so. Then, the freezing rain begins. The question becomes how long does the cold air damming remain in place against the intrusion of the warm air behind the coastal front moving from SE to NW. Here’s where the short term modeling comes into play…

Up to this point, we’ve been using large scale, coarse model grid points. Now, in the short term, the grid spacing gets much tighter, and more reliable for resolving local-scale problems like… “How far west will the surface freezing line make it?” This is key to Raleigh. The longer we stay below freezing, the more crippling accrual of ice we get.

No need to guess tonight, I’ll provide more precise ideas on what that looks like in a post tomorrow. Tonight, the key takeaway is that Sunday looks to be a treacherous travel situation. Make alternate plans.

Bonus… some of the short term models suggest that we may see a period of snow Sat afternoon. Should be inconsequential, but pretty!

Ice, Ice Baby?

Lots of time before this event… Tonight, the best guess for Raleigh is for a little bit of snow — to significant sleet — to significant iceand then rain at the end of the event.

Happy New Year!

I could/should wax poetic over the couple of different scenarios on the table as to our impending winter weather event. However, the main message to convey is that a significant winter storm is likely to impact Raleigh west thru the mountains, beginning early Sunday morning (earlier from the west to east).

As disappointing as it might be for clarity, there’s no need to hypothesize as to scenarios until we get closer in the Fri PM/Sat AM timeframe. Honestly, all solutions are on the table at this point, and we’ll probably waffle back and forth over the next couple days.

Tonight’s read indicates an impactful snow to sleet to freezing rain to rain event in Raleigh. Then, along a gradient as you go west to Greensboro you’ll see an all frozen… more snow, more sleet and freezing rain.

Happy snow-dreaming!

Things Are Looking Up…

…as in, I’m looking to up expected snow totals a bit… albeit with the risk of a Charlie Brown, Lucy, football reenactment!

A consensus is forming in the numerical guidance with regard to tonight’s snow event. QPFs have trended higher, which will lead to greater cooling of the column, which will lead to higher snow totals across the northern half of NC.

We should see precipitation break out in the Triangle in the form of rain around 9pm. Then, we’ll see that typical cold, NC winter rain thru midnight. Between midnight and 1am we should see the changeover to all snow. Precipitation rates look to be moderate, so I would expect some picturesque moderate to even heavy snow. There will be a window of just 4-5 hours for the snow, and most of it should be wrapped up by dawn. If you want to see it, set those middle of the night alarms for 3am!

Expected heaviest accumulations north of a line from Greensboro to Raleigh to Wilson. Totals will range 2-4″ with perhaps some 5-6″ totals toward the Virginia border. A good target for Raleigh is around 3″. Bust potential to the downside will be just a dusting. Bust potential to the high side would be 5″.

Ground temps and particularly road temps are fairly warm, so this accumulation will be primarily in the grass, especially early. Although with the anticipated heavier snow rates, the roads could eventual succumb to the snow. However, once the snow stops and the sun comes up, any problems will quickly dissipate.

I’m still eyeing the next system for Sunday. However, we may turn out to be on the warm side of that, but it’s something to continue to monitor. And especially interests north and west should keep tabs on the latest.

Winter Weather to Return to NC

A quick heads up on the system for overnight Wed into early Thurs AM that we’ve been eyeing for over a week now. Just as hope was fading, the numerical modeling has strongly trended to a more favorable alignment of the surface low and upper-level energy over the past day or so. And while this won’t be the ‘big one’ or anything like that. It does appear more likely that rain will changeover to snow late Wed night with the potential for light accumulations especially on grassy areas.

There is the potential for some moderate banding in this scenario which could yield higher lollipop totals scattered among a more general swath of 1/2″ to 2″ snows. There’s still plenty of time to follow the latest trends tonight and thru the day tomorrow.

Perhaps of more interest though is a second potential winter event late Sat into Sunday that advertises as what could be a more prolonged bout with a mixed bag of all p-types for a winter mess of significant accumulations of ice, sleet and snow across a good chance of NC.

Minor Event for the Triangle

Happy 2021! It’s good to have a winter weather event to talk about!

For Raleigh, it looks like the initial precip begins between 3 and 5am. Probably initial as rain, with a brief changeover to a sleet, rain, wet snow mix, which then changes over to all rain as we approach rush hour. Any wintry p-type in this first round should be of no consequence.

During the day, the rain will be spotty and light with temperatures hovering in the mid-30s. (a beautiful day!). Then tomorrow evening in the 7-9pm range snow showers will begin to break out in response to the cold upper-level low rotating thru. We’ll have a 3 to max 4 hour window til just after midnight of snow showers, some of which have the potential to be moderate. This is will be the time when Raleigh sees the potential for accumulating snow, in particular on grassy areas. Most likely, accumulations will be 1/2″ to 1.5″. Bust low would be snow in the air, none on the ground. Bust high would be 2-3″. Snow totals will not be uniform. They will be banded more like what you see with thunderstorm distributions in the summer.

Enjoy!

I Was Wrong

Couple of things…

1) the antecedent ground temperatures really held their own — while it was snowing really hard, it worked. but now the precip rates are winding down earlier than anticipated, which brings me to…

2) the axis of enhanced moisture never extended as far north as advertised— that means that the NE corner of the state that was expected to be the winner will end up underfed. In Wake county, while the snow coming down now is lovely, there will be little to no additional accumulation.

Still the temps will drop well below freezing tonight and all that slush on the roads will be treacherous tomorrow. The question then becomes how much melting and evaporation do we get tomorrow…should be a lot… to prevent more back ice on Sat AM when temps will plummet to the lower 20s.

Then… guess what… I’m watching the potential for another winter event next weekend! Fun times. Enjoy!