Weathertrex.com

The current thinking on the weekend wintry weather is that Raleigh will be (slightly) on the warm side of the action.  Could be.  Or not.

Remember when you were a kid playing on the seesaw?  Did you ever play with the kid who was so very close to your weight that you could nearly balance each other?  Didn’t really matter how close, just that he/she had that extra little mass that tipped the seesaw in their favor.  And once tipped, it was all out.  They were on the ground; you were in the air.

And so, this weekend’s setup is a bit of a meteorological seesaw.  The atmosphere is really close to that tipping point where no wintry precip transitions to sleet with heavy wet snow to lots of heavy wet snow…all while surface temps hover just above freezing.

Right now, I’d be on alert for areas north of hwy 64.  This will be one of those situations where the numerical guidance will have a hard time exacting the boundary.  We’ll have to wait until tomorrow evening to really see how this plays out.  The safe bet is that Raleigh just gets a coating of white stuff.  The reality is that Raleigh could get a lot more.  And depending on where that tipping point falls (the gradient will be sharp), we could see a situation where the northern part of the county has significant accumulation, while the southern part is clear.

Let’s figure this out tomorrow!

First off, about the snow for tomorrow (Wednesday)…  it’s not a big deal.  Just like last week wasn’t a big deal.  I don’t generally post unless there will be a significant impact from an event, or i’m intrigued by the possibilities.  So, I’m actually posting now, because I’m intrigued by the potential for a Palm Sunday snow this weekend, and not what will come tomorrow.  It’s a good thing my church is smart and employs a meteorologist to guide them through any meteorological mayhem during the high holy days! 😉

And talk about climatologically unfavorable!  The setup for Sunday is out of the ordinary a) because it’s so late in the season, and b) because of the clipper-like nature of the low diving south of us from the northwest.  We generally don’t get appreciable snows from clipper systems, and many of them go over top of us or to our north, leaving us on the warm side of things.  This could be different.  There is some evidence to suggest that the March Madness that started last weekend with Virginia losing in the NCAA tourney may continue for us with a rare snow.

It’s a hundred years off in meteorologist-time, so a lot can and will change.  But it’s something to watch and see how it develops.

we’re off!

And snow it begins…

Snow is now accumulating over Wake County.  I’m comfortable with last night’s forecast of 7-9″.  However, the latest short term modeling and upstream reports indicate that those numbers may still be too low for western Wake County and back to to Durham/Chapel Hill.  So, we may be looking at 8-10″ with some lucky locales that push a foot.

Enjoy!

…not really, but we need to up these totals.

I understand the need for the NWS and news outlets to be cautious, but all the modeling indicates heavier snow totals in the Triangle and in general across the state.  Ensemble means are running near 5″…impressive.  The latest short term and global American models this evening depict well over 1/2″ of liquid equivalent.  With snow ratios likely to run greater than 10:1, it should be easy to achieve snow totals in excess of 6″.  We shall monitor the overnight runs of the Euro and the short term models.

Bottom line…I’m expecting 7-9″ across the Triangle.  Snow begins early morning (mixed with rain) and really begins to kick around 8 or 9am.  Expect moderate to heavy snow for 6-8 hours, lightening up to spotty snow showers in the evening.

The fun begins soon!

Today’s modeling has come into excellent agreement on central NC receiving a significant, moderate snowfall tomorrow.  All the deterministic numerical guidance and their ensemble suites are very similar in depicting an axis of moderate snow accumulations near the Triangle.  Ensemble mean totals are rising, so confidence is pushing even higher for this event.  There will be a broad swath of 1-2″ across the majority the state with the axis of heaviest snows roughly along a line from Southern Pines to Raleigh to South Hill, Virginia.

Questions…how much rain, if any at the onset?  …liquid to snow ratios will be how high?  …where exactly will the favored axis line up?

Expect precipitation in Raleigh to begin as a spotty rain/snow mix as early as 4-5am, but really get going closer to 6 or 7am as moderate to occasionally heavy snow into the afternoon.  I’m expecting 3-5″ in Raleigh.  The over/under on the bust scale is now more like 6″ and 2″.

Enjoy your grocery run!

Quick post to say that the overnight models have come in more bullish with the available moisture.  More importantly, they are beginning to agree with each other and converge on a solution that paints the favored axis of heavier snow totals centered a little farther east, closer to the Triangle.  Therefore, I’m willing to raise snow totals a bit in Raleigh…rather than 2″, it’s probably more like 3-4″.  And the over/under bust potential something like 6″ and 1″.

More later…

Confidence is increasing for snow on Wednesday.

As I said over the weekend, this is not a setup for a lot of snow for us.  And this is not a pattern that NC will typically see a lot of snow.  There is no surface storm (although a low will be forming off the coast with few consequences for NC).  All of the precipitation will be driven by upper level dynamics and frontogenetic forcing.  We have a reinforcing shot of cold air that will arrive overnight Tuesday.  However, ahead of that arctic boundary, temperatures should warm close to 50° tomorrow.  Most modeling indicates that the cold air surging in behind the front will easily overwhelm the warm boundary layer as the moisture arrives.  It’s a tricky situation, though, and I can’t even count the number of busted forecasts where the cold air arrived later than expected and a cold rain dominated before an unsatisfying changeover to snow at the end. #NCMeteorologistRecurringNightmare

So at this point, we shall cautiously proceed with a forecast for Raleigh that looks like:  Mild temperatures Tuesday dropping overnight to near freezing as the precipitation arrives between 7-9am.  Precipitation probably begins as a rain snow mix, but should changeover fairly quickly to all snow.  Accumulation of about 2″ in Raleigh.

Over/Under Bust Potential:  4″ / Dusting

Will update tomorrow with the latest.

If you’re tired of this wet sticky muggy blah of the past couple days, have no fear. Winter returns Sunday with temperatures stuck in the 30s for the first of the week ahead of a reinforcing shot arctic air on tues.  In an atypical setup for NC snow, we’ll look for a wave to setup on the front and spread snow over much of the western 2/3 of the state Wed.  It’s too soon to know details, of course, but something to be aware of for planning.  More details over the weekend…

The Krispy Kreme Challenge has been a mightier task than imagined, but the snow is imminent for Raleigh.  The snow should envelop all of Raleigh by 8:30.

The null between the two areas of precip has come to fruition and so, what could have been, will be less.  Still think that an inch plus is possible given upstream observed accumulations.

Patience young, Padawan!