January 16: Snow on the way!
Another winter storm is on the way to central North Carolina, with snow becoming likely after midnight tonight and continuing through much of the day on Wednesday.
We’re in the “calm before the storm” today, with temperatures warming up to the upper 40s despite increasing clouds this afternoon:
Those temperatures will drop off this evening, and it will likely be cold enough for the snow to stick once it starts to fall. This is the RPM model’s simulation of what the radar will look like tonight and tomorrow:
Keep in mind, that’s one version of one model…the other models we use are in pretty good agreement, but there’s always a little uncertainty regarding the minute-by-minute timing. Factoring in the other data, here’s when we expect the snow to start late tonight and early Wednesday:
And here’s when we expect the snow to wind down Wednesday afternoon:
And now for the million-dollar question…HOW MUCH SNOW? Simple question, complicated answer. First, here are the latest numbers for the Triangle from the various forecast models:
Those numbers are a little higher than previous forecasts, because it looks like there will be just a little more moisture in the atmosphere available to produce snow. But there’s an important note on that graphic — the forecast models don’t account for any of the snow melting as it hits the ground. While that won’t be a major factor this time around, there will be some melting and compacting of the snow as it accumulates.
Accounting for those factors, and weighing in the historical accuracy of various forecast models, here’s the pattern I expect by the time all is said and done late Wednesday:
The National Weather Service’s forecast is very similar:
That’s more than enough for the NWS to issue a Winter Weather Advisory, which kicks in at 11pm today and continues through 7pm Wednesday:
I wouldn’t be surprised if areas from the Triangle northward are upgraded to a Winter Storm Warning — but regardless of the specific advisory/warning, take some time today to get ready.
IMPORTANT: This is not the FINAL snow forecast! We’ll get more data throughout the day, so we’ll continue tweaking the pattern and specific amounts to give you the most-accurate forecast possible. Follow us on social media (links at the bottom of this post) for updates — and of course we’ll keep you updated during our newscasts as well. For now, here’s what you need to keep in mind…
- While NC DOT will be pre-treating the roads all day, untreated roads will quickly become slippery or even hazardous once the snow starts. Wednesday morning’s and Wednesday evening’s commutes both look to be nasty.
- I’m not in the business of predicting specific school delays/closures, but it’s safe to say we’ll be looking at a long list both Wednesday and Thursday. Have a child-care plan in place.
- Once the snow ends, temperatures will drop to the teens by early Thursday morning, so roads conditions will still be an issue for Thursday morning’s commute. If you have the option to work from home, I’d exercise that option both days.
- Road conditions will improve Thursday, with abundant sunshine expected and high temperatures well above freezing. So you don’t need to panic-buy a month’s worth of break, milk and toilet paper today.
The most-frequently asked questions…could it snow more than what we’re forecasting? And could it snow less? The answer to both is YES. We’re talking a setup where just 0.08″ of liquid will produce 1″ of snow — so just a minor change in the amount of atmospheric moisture can result in a big change to the snow forecast. And that’s why winter weather forecast drives us a little crazy!
As if the snow isn’t enough, wind chills will be dangerously cold by Wednesday night:
The warming trend that will start to kick in Thursday will be much more noticeable by this weekend:
So to recap: we set a record low of 4 degrees a week ago Sunday, we hit the low 70s with thunderstorms Friday, we’re looking at accumulating snow tomorrow, then we’ll be back to the 60s by this Sunday. Okay then.
Just a reminder: Twitter is BY FAR the most-useful social media resource when it comes to a rapidly-changing weather scenario. Think about how many times you see a friend’s picture in your Facebook feed 48 hours after it’s posted — you don’t want your weather info to be that out of date!
Instagram: Paul Heggen
(And no nerd-links today, sorry…winter weather forecasting is time-consuming!)