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…the “Special Lady at the Waffle House”

Yesterday we talked about a more suppressed storm track and what that would mean for us.  Some of the runs have shown some reeeeeally suppressed solutions (6Z GFS had no precip in NC) and even the operational 12Z Euro is pretty far south, with NC on the northern edge of the precip shield until the low rounds the bend at the coast heading north.  In this scenario, east of I-95 gets the worst of it.

But this far out, as much fun as it is to look at each model run come in, we really need to paint with a broad brush of generalities.  What we’re likely to see are track solutions jumping back and forth before settling down over the weekend.  At this point, I am expecting a significant winter episode for much of NC early Tues into Wed.  We can talk amounts and ptype over the weekend.

One more thing to address…the well-advertised cold we have now and even colder shot coming Sat night will set the stage for any frozen precipitation to quickly cause problems.  Many times with NC winter events, some portion of the initial snow or sleet is lost from accumulating because of warm antecedent ground conditions.  This will not be the case this go round.  (Remember when .3″ of snow caused 10hrs of gridlock back in 2005?!  That was primarily because the roads were very cold to start with.)

Stay tuned.  It should be fun to see how this evolves.

Ok, so maybe a plan hasn’t come together, but at least we’re beginning to see convergence in model solutions.

I’ve said for days that a winter weather event mid next week fits the pattern, and now the latest 12Z suite of model guidance speaks with a voice of unanimity of a more suppressed storm track and slightly quicker timing than previously depicted.  These two items work in favor of a significant wintry mess.  The suppressed storm track means we would be squarely on the northern side of the storm track (colder).  The moisture arriving quicker would ‘lock in’ a cold air wedge at the surface from strong evaporative cooling realized by dropping moisture into the abnormally cold, dry air initially in place.  As far as sensible weather…this would mean precip begins as snow, then changes to sleet, then freezing rain.  More snow and sleet north and west.  More sleet and freezing rain south and east.  Then rain to the south and east of the freezing rain.  That’s the plan.  Where does the transition zone lie?  If you believe today’s runs, then the Triangle would spend the majority of the event below freezing.

Only problem…it’s five days away!  At this point nothing is set, but the pieces are there.  We’ll see if they align.

Wow…more Ws than a CSI investigation!

Long time, no blog.

Not that we should get hyped up about a potential day-8 event, but this winter that’s about the extent of what we have to cling to.  I’ve been bored with the winter weather drought and fed up with the 30-something rains…so let the snow mongering begin!

Before we get to the hypotheticals of 7-8 days out, let me affirm the significance of the cold air on the way for this weekend.  It will be impressive.  Lows in the low teens, and highs on Sunday (despite a lot of sun) in the mid 20s.

Then as the pattern relaxes a bit after that, how quickly will a southern stream disturbance arrive in NC where the cold resides?  Long range modeling has been

hinting at a confluence of the two for a couple of days.  Over the past couple of model run cycles there seems to be more agreement that a storm with a southerly track will affect the SE by mid-week.  How the low tracks is up for grabs…and as you know, you’ll want to be on the northern side of the track to receive wintry precip.

That’s enough for now.  Just be alert the possibility.

And…I’ll tease you with a new game that I’ll introduce in tomorrow’s post. 😉

First off, the apology…as advertised from the beginning, the question for this event was to be the precip.  As it turns out, the much bemoaned and berated GFS will win the battle of the small QPF reality.  The primary area of precip is heading off to the northeast toward Norfolk now.  As expected, the max ice accruals will be just north/east of Raleigh.  However the totals across the board will be less than half of what was expected.

Of course, this is all good news from a safety and disruption standpoint…but not so good from a ‘i changed my plans’ perspective.  Again, apologies for my being fooled on this one.

So for the remainder of tonight…the major precip is done.  There will continue to be showers of freezing rain, freezing drizzle and perhaps even some sleet later on as more cold air works in the column.  These showers should prove to be little or no consequence.  So most places near Raleigh should end up with a glaze to a tenth of ice at most.

Looking forward…we’ll have a warm up over the next week before turning back cold end of next week into the last week of Jan.

…shaved, crushed, cubes?

Everything looks more or less on track.  However, I’m puzzled as to why we’re calling off after school activities today, but I suppose somebody get’s big bucks to make that decision.  As to timing of onset, things in Raleigh shouldn’t begin in earnest until after 10 this evening. There will continue to be a couple of passing showers and areas of drizzle, though. The main precip shield hasn’t even developed yet.  When it does, nowcasting it’s arrival should be much easier.  Then overnight the majority of the precip will fall in the form of freezing rain with some sleet mixing in, especially north.

And I’m thinking to maybe dial back the ‘sweet spot’ totals I mentioned to up to .4″ with the next band of counties to the west to up to .25″.  These aren’t really material changes in terms of impacts, but I wanted to dial the totals to reflect what’s more likely, rather than what is possible.  Again, once the precip shield develops this evening we should be able to get a good handle on it, as opposed to believing a bunch of 0s and 1s some oversized calculator is crunching.

Quick update…

Overnight models have trended wetter with the GFS finally on board.  The new 12 NAM is in and continues bullish for significant event.

Particularly Raleigh and north and east should see the most problems.  Heading towards Durham and west they should have less icing.  The axis of heaviest moisture will be along the I-95 corridor and east.  So there will be the sweet spot of heaviest ice accumulations that balances the cold to the west and moisture to the east.  This looks most likely to be in Wayne, Wilson, Nash and Halifax counties where ice accumulations will be up to .5″.  Then the line of counties the west of that…Harnett, Johnston, Wake, Franklin Warren, Vance should see accumulation up to .3″. Then west of there, up to .1″.

Remember that .25″ is a good guideline for when an ice storm becomes bad in terms of downed trees and limbs and widespread power outages.  Further exacerbating this event will be the fact that the ground is very wet from a lot of rain yesterday and even this season.  So we may see more uprooted trees than normal with this storm.

You’ll see the NWS upgrade the winter storm watch to a warning this afternoon.  So, now is a good time to begin making alternate plans for tomorrow.  Also check to make sure you have extra batteries,etc…  Oh and don’t forget to buy lots of bread, milk and beer! 😉

More updates as more model data comes in.

And for more frequent, short updates, follow me on Twitter at trextrex14

It’s been a while since there’s been much to talk about in terms of wintry weather for Raleigh (aside from a quick blast of boo chilly air last week).  So today, in between monsoonal downpours, we are watching the potential for a significant icing event overnight Tuesday thru lunch on Wednesday.

A fresh supply of cold air will begin arriving in NC as the rain exits later this evening.  So, the extent of low level cold air supply will not be in question.  The uncertainty will be in how much precip will fall in the Triangle, owing to a weak surface low riding up the coast.  The axis of heaviest precip will certainly lie to the east of Raleigh.  The extent to which it bulges back westward will be the question.

Models differ on this, ranging from just some drizzle and a hundredth or two of liquid equiv, to up to a 1/4″ of liquid equiv (QPF).  At this point, I would expect around a 1/10″ of ice accumulation, which will be enough to make for bad driving and a few problems, but not result in widespread power outages and/or bring lots of tree limbs down.  We’ll watch to see how the numerical guidance trends with QPF over the next day to get a better handle on if this will be just a nuisance event or something to make alternate plans for.

As to timing…It appears that we will be lucky that the freezing rain should begin late Tues evening (10pm to midnight) and continue overnight into Wed AM.  This should help with fewer travel problems, and let people evaluate the conditions Wed AM before venturing out.

More updates later.  But if you would like more frequent updates, follow me on twitter at:  trextrex14

Ok, no Thanksgiving blizzard for Raleigh, but maybe there will be some snow in NC on Wednesday with the potential for some hefty snow in the Mid-Atlantic and NorthEast to make for a ‘gizzard blizzard’!

There is mounting evidence to suggest the possibility of a wet snow event in central NC late Tuesday and Wednesday.  The cold will be marginal, but heavier precip rates might be able to overcome warm boundary layer temps.  Alternatively, we could have everyone’s favorite…a cold 35° rain.

Still a lot of uncertainty and variety of solutions to study.  At this point the euro ensembles give it a 1 in 3 shot of measurable snow.  The operational GFS has been bullish for the past couple runs, but it’s interesting to see that the beta version of the new GFS upgrade which has been performing well, isn’t biting…yet.

I figured I should turn the snow showers on for the webpage…

Happy start to winter!  Don’t worry what the calendar says.  Next week a monster arctic high (especially for Nov) invades the US with A LOT of cold air.  Cold temps arrive here at the end of the week, and then could there be an over-running situation late Fri or Sat?!  something frozen?!

It’s a long way off and lots to debate over the next week, but what looks like a great bet is the cold!

Oh, and watch out for one more round of mod to heavy showers with maybe a clap of thunder before the night is out.