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This evening’s post was my first attempt at posting via mobile.  So I used Siri to lessen the typing.  And then I didn’t have time to proof.  I’ve corrected the post now, but there were some funny things!  Ha!

How’s this for a front! (valid tomorrow AM)

The latest American models continue a wintry threat, if even a bit less bullish.  But there’s really not an appreciably significant difference.  Tomorrow, as the time horizon of interest comes into range of the  high-res short-term models, we will evaluate along with radar trends to see how many problems we’ll have.

HOUSEKEEPING ISSUES…some of you have voiced concern that you have not been receiving emails when I update the site.  I’m not sure what’s wrong, but will look into it.  In the meantime just check back to the top page (don’t use a link from an old email because it will mostly likely take you to a specific post).  Navigate to weathertrex.com directly and you will always get the latest post.

As hard as it is to imagine with springlike temps well into the 70s, winter make a triumphant return tomorrow. The cold front is spectacular. It will come through later tonight and the real cold air arrives tomorrow during the day. Temperatures will fall through the day such that by late afternoon temperatures will be near freezing. The sooner you get to freezing the more time the moisture has to work with the cold air. So this event will set up with the highest ice accruals and sleet accumulation in a north to south gradient.  The models are trending a little wetter with the backend moisture over the past couple of days, such that now much of the northern half of NC will see at least some freezing/frozen precipitation.

It looks like there will be combinations of freezing rain and sleet as the predominant P-types when the rains changes over. Determining how much of each of those you get will drive how impactful the storm will be.  If it’s predominantly freezing rain, it will take longer to cool the very warm ground temperatures from today’s beautiful weather. However, if there’s an appreciable amount of sleet involved, then roads will become impacted much sooner.

Overnight lows tomorrow evening will be in the upper teens, so black ice will be a problem regardless of if it freezes on contact or freezes later overnight.  Best guest for Raleigh will be up to a 1/2 of sleet and 1/10″inch of glaze in the trees and elevated surfaces. Durham may be a little higher on those totals. And certainly towards the Virginia border and Roxboro… They will see the most significant impacts from this storm.

Lots of time still to watch, and watch we will. Looks like another snow day for the kids on Friday.

As I mentioned before, this will not be a good setup for a significant event.  However, it does seem probable that the rain will change to sleet and maybe some freezing rain late Thursday as the cold air invades.  Big changes from the 70s tomorrow to falling temps thru the day on Thursday.  Ground temps running higher will help limit any appreciable accumulation.

Will continue to watch as we get closer, of course.  It will be a borderline situation no matter how you slice it.

I know we’re not used to it, but tomorrow will be your one day with the sun out that’s above freezing!  Yes, Wednesday could be pushing 70 (with rain)…and that’s where the fun begins.  We’ll get a roaring southerly flow ahead the next blast of cold air.  And it looks like as the cold front comes thru, it will stall just along the coast.  So markedly colder air will be infiltrating NC as a wave of low pressure uses the frontal boundary as a guide to move north with more moisture.  If this scenario materializes, we would see rain change to sleet and eventually to all snow later Wed night into Thurs AM.

A couple of caveats…it’s 4 days out, this is not a typical snow setup for NC, we will have warm temps ahead of the front earlier in the day and it is now March so sun angles are really climbing.  Having said all that…the GFS has been pretty consistent on insisting this and there is support from the Euro and ensembles.  What’s two more snow days among friends?!?!

Yes, it looks like there will be some minor icing tomorrow AM.  But this will not be a major event, if fact there should be few if any problems in the Triangle.  It looks like the rain will be light and patchy in the early AM and thru mid morning when temps will be below freezing.  That being said, anything that falls should freeze easily in the trees and elevated surfaces.  It’s just that there shouldn’t much until later when the temps should rise above freezing.  Heaviest icing will be west of Raleigh toward the Triad where more moisture is expected sooner.  For Raleigh, expect a light glaze at the most.  Roads should generally be fine, but as always watch those bridges and overpasses first.  We’ll watch it tonight to make sure nothing changes.

Happy Snow!

If nothing else, it’s pretty!

Heavy snow will arrive in Wake Co. over the next 2 hours.

Wake County looks to be just on ‘the line’.  Southern Wake might only achieve 3, 4, 5″? while northern Wake may achieve 8-10 or a foot.  Or…will the transition zone creep even farther north another 30 miles, as some of the latest short-term modeling indicates?

Hard to say.  What I will say is that 4″ is a lock for most in the Triangle and north.

The 0Z models indicate even more liquid equivalent.  If that’s right, then there’s more room for any mixed precip in the totals to still allow for earlier snow outlines, even if the wintry mix transition zone flirts farther north into the Triangle.

At the risk of ‘jumping the shark’…sing this to yourself…(to the tune of Let It Go)

Epic snow, Epic snow!

Can’t hold it off anymore

Epic snow, Epic snow

By the end you’ll scream…no more!

The snowstorm that many in NC dream of is potentially lurking just around the corner.

The main question mark is…how far north does the warm tongue penetrate?  This could cause a 6″ or more differential in snow totals.  The trick in nailing this forecast will be accurately assessing how far north it gets.  Just to the north of that will probably be the axis of heaviest snows.

What if the forecast is a bust…I think the low end bust potential for the Triangle is 4″.  However, I think the Triangle will probably end up at the southwest corner of the swath of heaviest accumulations.  (See the graphic).  In this axis, accumulations of 7-10″ are likely.  But there is potential for more than 1 foot.  As I said last night, to the south of this band, the gradient to light accumulations will be much sharper than to the north.

The models are in complete agreement for copious QPF (liquid equivalent) for the event.  For Raleigh, 1.25″ of liquid equivalent is the consensus.  Knowing we’ll begin as rain and be above freezing, let’s take away 0.25″ to rain and melting at the beginning.  Then, take away another .2″ to account for any sleet and freezing rain that might mix in.  That leaves you at .8″ –> 8″ at 10:1 or about 9.6″ at 12:1.

(There is one little fly in ointment for realizing all this QPF that I’ll not discuss yet, but will watch and talk about later tonight, if necessary.)

What to expect…this evening, rain will breakout 6:30-7:30pm and change to heavy snow between 9 and 9:30.  There will be times overnight when it snows 1 to 2″ an hour.  We’ll be watching that warm air to see how far north it makes it.  But any way you look at this, it’s going to be a major event.  Enjoy.

The same caveats from earlier apply…we’ll see if we stay 100% snow for the event to realize max snow totals.

Tomorrow should be a good opportunity to get out during the day.  No trouble until late night Wed.

ABOUT THE NOW…

From an accumulation point of view, a call of a dusting to an inch wasn’t too bad.  The better call was to bite on the later guidance suggesting slightly heavier amounts and call it 1/2 – 2″.  Today’s snow actually seemed like more than it was because…1) it was very cold this AM, which initially made for efficient laying on roads, and 2) all it takes it about 1″ to cover everything in white and it looks more impressive than it really is.  Snowfall reports around the Triangle were lighter towards Durham (1/2″) and heavier in Wake Co. (up to 1.5″).  Not much in the grand scheme of things…and not much compared to the potential of tomorrow night.

Aside…it has been really cool to see how the back edge of snow keeps regenerating over Wake Co.  As I write this at 4:30, it’s still happening.  And we’ll see another round train through over the next 30 mins.

ABOUT THE LATER…

Hopefully, you enjoyed today’s amuse bouche as a prelude to tomorrow night’s feast.  The situation still looks favorable for a significant snowfall in the Triangle and for a good portion of NC.  Not that everyone will get hefty snow totals, but a large swath will get some accumulation.  There is likely to be an axis of heaviest snows, and right now that band seems most likely to set up from Asheboro to Raleigh to Rocky Mount to Ahoskie.  Now you wanna know how much, right?

Having the storm track farther west is good to bring lots of moisture farther west, but it also means that the air will probably not be quite as cold as first envisioned.  For instance, expect ground temps to be above freezing for the first couple hours of this event tomorrow evening.  It will take some time to cool the surface to freezing and that will loose some snow to melting.  I can also see how initially the precip could begin as rain for a bit.  But then once the snow gets going it looks like it will come down heavily at times.

We do need to talk about the threat of the warm tongue knocking at the door of southern Wake Co. for a time. This could cause the snow to mix with or change to sleet at times and possibly near the end of the event have a little light glaze possible.  These are details to watch over the next 24hrs.

Before I give you what you want, I have to say that achieving a snowstorm of the magnitude indicated by this system’s potential is hard and rare.  There are several things to go wrong, any one of which could easily slash snowfall totals.  And to my point above about 1″ looking like a lot…really once you cover the ground, it’s really all bonus and there’s not much difference between 4″ vs 8″.  With all that handwaving out of the way.  The axis of heaviest snow looks to be along that line I outlined above with 6-8″.  North and east from Rocky Mount probably more than 8.  The totals taper down quickly south and east such that Fayetteville probably only gets 1 or 2″ with some icing or changing to rain.  Totals on the north side of that line will have a more gradual ramp down so that places in VA like Williamsburg still get a couple inches.  Snow will fly all the way back to the western part of the state with general 2-6″ depending on where you are.

More later!