Wednesday, February 12, 2014

Snow vs. sleet vs. freezing rain

The strong winter storm currently battering the Carolinas is carrying a mix of precipitation forms, and each of them carries its own risks.

All three types of winter precipitation -- snow, sleet and freezing rain -- are part of the storm system. And parts of the immediate Charlotte region will see all three forms during the next 18 hours.

It's the amount of the various forms that is still being debated.

First, a quick review of the three forms and their impact:

SNOW ... If the atmosphere is below freezing from tops of the clouds to the ground, the precipitation falls as snow. It remains frozen all the way to the ground.

Snow causes problems on the roads, of course, but it can be plowed or melted with salt. And it has no impact on power lines, unless the snow is very wet and heavy.

SLEET ... If a rather thin layer of milder air (slightly above freezing) builds in the atmosphere, the snow melts into rain about halfway to the ground, then refreezes as the air gets colder again. The precipitation falls as ice pellets, or sleet.

Sleet obviously bounces off everything, so it has no impact on power lines. But it is a real killer for the roads. Sleet has a habit of partially melting when it hits the ground and then quickly freezing again. It creates a crunchy, slippery road surface.

FREEZING RAIN ... If the atmosphere has a large layer of mild air, but a shallow layer near the surface is cold, then the precipitation falls as rain and freezes quickly at the surface. I've seen a lot of ice storms in which roads remain wet. But ice always forms on exposed surfaces like tree limbs and power lines.

The heavy weight of the ice eventually brings down the tree limbs and power lines. And people lose their electricity.

I prefer none of these, actually, but if we have to deal with something, snow is the easiest to cope with. Sleet is nearly impossible to drive in, but freezing rain takes away electricity, heat, lights and cable television.

Typically, ice accumulations of 1/4 inch or more are enough to cause widespread power outages. The Weather Service is predicting that much ice (or more) from the southeast suburbs of Charlotte southward.

13 comments:

Anonymous said...

Oh dear, oh dear......not good.

Anonymous said...

Ok. So where are all the critics now that the storm came as predicted and is dumping snow on us? Where are you? Hello? Anyone there. Trolls!

Troll said...

Here come the weatherman groupies swelling their chests...

Congratulations....sooner or later reality was bound to match their prediction. If you predict something will happen long enough, eventually it will happen.

Early prediction: We will have a few days of 99-100 degrees this July.

Anonymous said...

Okay, the snow is here. Is it really that bad? Has life as we know it come to a halt? If you're at home and can't get to work, get off your butts and go outside and play. Play with your kids. Play with your dogs. Stop belly aching. How often does this happen? Get outside, have some fun. You can always go back inside and get warm.

Anonymous said...

Lots of yankees, and I am from the North, don't understand what ice and snow does to a city such as Charlotte; our children are not prepared for the bitter cold bus stops, our service workers are tring to work and yet still get home to their families, our elderly will try to drive to prove their independence, and the city/county does the best it can. Sorry but in the South we don't have the resources to salt and plow the streets for the rare snowstorm. I too am tired of snarky comments about bad weather in the South. It's funny once, then try losing power for 12-24 hrs with small kids at home if you are a FT working Mom, or try driving in a neighborhood with ¼ in black ice. Worse yet your teenage driver tries to get home in that mess... get over yourselves ..every time we have bad weather the transplants start posting the usual mocking, tiresome, and thoughtless comments...please don't embarrass us with this blather ...

Native NC Troll said...

The "negative" comments are not about the weather itself, nor the civic response to it, but rather of the hype and drama produced by the forecasters, and the panic-driven reactions of SOME residents, regardless of their region of origin.

There is no indication that any of the "negative" comments originate from northerners. Many Southerners also sneer at the bizarre behaviour these storms bring out in people.

It will all be over in a day or two.

Anonymous said...

Why don't you tell us what the weather is doing now, and what it's going to do Thursday, instead of giving us definitions for sleet and freezing rain? Readers can look up the differences themselves online.

Anonymous said...

PANIC BRAD PANIC.
24 HOUR TEAM COVERAGE. DO NOT LEAVE THE TV.

leave your home and walk to the nearest grocery store when it stops snowing. make sure to get more bread and more milk, youll need it to survive.

Anonymous said...

I grew up in Upstate New York, so I know about snow storms. Been here for over 20 years. Those I know who are still in that area assure me that even there, where yearly snow falls are 80-100 inches, hype is present. I think that in our new age of hundreds of channels, broadcasters need to draw in viewers with story lines. Weather means people pay attention. Up there, schools are now closing for cold: unheard of in my days of trudging to school in -20 temperatures. So, to those who want to snicker at the natives and their reaction to storms, know this: "hype" is not a product of the South. Plus, this happens once every 10 years, which is why it is played up. So, like a previous poster wrote, go out and enjoy the white stuff. For all my fellow carpet-baggers, lay off the snarky comments. This place is awesome. If it wasn't we'd still be shoveling snow in April up there, so chill out!

Marconi Polonius said...

People in Charlotte pee their pants at half an inch of rain.....If Charlotte got hit with one or two feet of snow,there`d be a collective coronary amongst the people! To the lady above who said the people of Charlotte are not prepared for something like this,then you GET prepared! You may not need to use it but once every few years,but it`s good to know you have the prep in place....I lived in Charlotte from 2002 to 2009 and was amazed whenever snow or severe thunderstorms happened,the people just freaked out,not having a clue how to get thru the weather event!

Anonymous said...

Florida Seminole would have clobbered Auburn had they played in Charlotte for the Orange Bowl championship match, in this past weather alert storm.

Loyal TV Forecast Watcher said...

The snow is melting away, and I am now stuck with five gallons of milk, and six loaves of bread! I was lead to believe I would be trapped in my home for weeks with no power.

I trusted those weather forecasters standing out in the snow all night warning me!!! How could they have let me down? How could it have happened that we now have clear roads a day after the snow?? How??

Anonymous said...

Old news....yawn....yawn......