Monday, November 29, 2010

Trouble late Tuesday ... and beyond

Another round of stormy weather is headed for the Carolinas later Tuesday, and the computers hint at more trouble -- possibly of the frozen variety -- late next week and about two weeks from now.

Some rapid and major changes in our weather will take place over the next 24 hours.

A flash flood watch already is in effect for Tuesday and Tuesday night for Burke, Caldwell, McDowell, Rutherford, Watauga and Wilkes counties in the Charlotte region. Additional watches and warnings are likely Tuesday.

Today, we're locked in a chilly pattern, governed by high pressure off the East Coast. But the seeds of change are visible. The cloud cover that thickened overnight is a telltale sign of the moisture surging into the Carolinas from the Gulf of Mexico.

By later today, low pressure will move eastward from the Arkansas-Texas area. Rain gradually will spread into the Carolinas, falling mostly in the mountains initially but reaching the foothills and Piedmont by later this afternoon.

It will be a chilly rain at first, with temperatures staying in the 40s today and dewpoint readings also in the 40s.

But a warm front on the east side of the low pressure system will move northward Tuesday, crossing the Charlotte area sometime in the morning. That will push our temperatures into the 60s, and the dewpoint temperatures will follow suit.

The Carolinas will be in the warm, unstable southeast side of the low pressure system by Tuesday afternoon and night, and that's where severe weather takes place.

Chris Horne, of the National Weather Service's office in Greer, S.C., says strong thunderstorms and heavy rain are forecast across the Carolinas, with the most likely area for severe weather being in the Piedmont.

"Some degree of thunderstorm wind damage threat -- perhaps even a tornado -- should exist into the night," Horne said.

These likely will be those sneaky severe storms -- the kind we experience in the Southeast during the winter. They move extremely fast, sometimes at 50 mph, and often have little or no lightning to herald their arrival.

And looking ahead? This part of the discussion is based on some GFS computer model projections for Dec. 8-9 and again Dec. 13. The GFS is one of several computer models used by meteorologists for long-range forecasts.

First, an important caveat ... long-range computer model forecasts often don't pan out. The science of meteorology has a tough enough time predicting 24 or 48 hours ahead. Forecasts such as these -- 192 to 264 hours in advance -- are iffy.

But the computers show a pattern of low pressure systems forming over the Southwest and moving across the Southeast and up the East Coast. This is exactly the pattern predicted by a number of long-range forecasters for the winter.

The big questions are: 1. Which path will the storms follow? 2. How much cold air will be in place in the Carolinas?

The storm path is important. If the Charlotte region remains on the north and west side of the storm's center, we're more likely to see cold rain or frozen precipitation. The GFS model has been waffling on the storm expected to affect our area Dec. 8-9, predicting a chance of frozen precipitation one time, then making it a rainy forecast the next. These models are updated a couple times each day.

However, the Dec. 13 storm system has been predicted consistently to remain east of the Charlotte area, putting us at a risk of something frozen.

I mention these GFS forecasts not to sound an alert about an upcoming ice storm. I think the computer models will change a bunch of times between now and then. In fact, the storm might never develop.

But I introduce the topic now, because we'll be dealing with it a lot this winter. Let's see how these long-range forecasts fare.

17 comments:

Anonymous said...

We know the truth. You are simply trying to drive up milk prices at HT.

Anonymous said...

LOL - I've never understood that. First, the storm's effects typically last only a couple of days - rarely preventing at will travel. Second, if you were to be "snowed" in for a day or so, why milk and bread? I'll stick with beer and doritos thank you very much :-)

Anonymous said...

You gave us the before and the after, but can you tell us what to expect on Dec 11. That is the date of the Thunder Road Marathon in Charlotte?

Anonymous said...

Steve, you know what GFS stands for? Good For S#!T. Don't trust it beyond 24-48 hours. It is nearly innacurate 100% time.

Anonymous said...

Thank you for this information. It reminds me to keep checking the forecasts and heed the results for my safety and well-being.

-Shelli

Paint pony said...

I agree w/ Anon. #2: we need the right staples in order to get thru being in "lock down". I would have to add hay and dogfood to my list. Winters in the Carolina Piedmont are like trying to dry off w/ a wet towel. The countdown until St. Patrick's Day has arrived!!Happy holidays.

Anonymous said...

Sorry it's BS warning about a 2 week away weather forecast. Gotta earn the paycheck somehow I guess

Anonymous said...

I heard it was snowing in London. I think that speaks for itself.

discourser said...

Replying to Anonymous - November 29, 2010 9:48 AM

LOL - I've never understood that. First, the storm's effects typically last only a couple of days - rarely preventing at will travel. Second, if you were to be "snowed" in for a day or so, why milk and bread? I'll stick with beer and doritos thank you very much :-)

Winter weather in our area is frequently accompanied by power outages preventing a mother from cooking hot meals. The milk is for cereal and the bread is to make sandwiches so the kiddies don't go hungry.

Anonymous said...

anyone remember the ice storm in December 2002? our power was out for 10 days, the temps stayed in the 40's for nearly 2 weeks, our asthmatic daughter wound up in ICU, it was a terrible couple of weeks. i mention it because - unless a storm comes through here and tears the rest of these leaves off the big trees, we might face a similarly damaging situation - leaves on the trees coated with ice, the weight bringing down thousands of large branches throughout the region.

USA Today headline: "Worst Ice Storm in Years Devastates the Carolinas." google search Charlotte NC December 2002 ice storm and familiarize yourself with what this is all about.

Anonymous said...

Need to start stocking up on beer and chips...er, I mean, milk and bread.

NC_Native said...

I'm sure that...as usual these days...the bulk of the rain will find a way to bypass Charlotte on all sides. Is there a bubble over this city or something??

Anonymous said...

I am almost certain the local T.V. stations get a precentage of the net bread and milk sales any period of time when the phrase "wintery percipitation" is used on the air. If something does actually make it to the ground and sticks, the net percentage goes even higher. So Al, it pays to say "wintery precipitation"

Anonymous said...

When all the new arrivals complain about southern drivers, shove this in their face.

"438 vehicles crash on icy Minn. roads
Published: Nov. 21, 2010 at 10:54PM

MINNEAPOLIS, Nov. 21 (UPI) -- Freezing rain iced up Minnesota roads, sending hundreds of vehicles slamming into each other and careening into ditches, authorities said Sunday.

The accidents began piling up Saturday and continued into Sunday, with the total reaching at least 438, the Minneapolis Star Tribune reported."

Anonymous said...

There's a differnece between driving on ice and driving on snow. Huge difference....

Anonymous said...

I'll probably catch some flack here but I always found the old wives tale of thunder/lightning in the winter being followed by snow 9 days later to be pretty reliable. Much more so than any of the forecasts I hear. We don't always get a lot but almost everytime we do get something frozen about 9 days later. Keep an ear out tomorrow - if you hear thunder, buy beer.

Anonymous said...

Please lets not have another Dec. 2002 mess. That ruined alot of folks Christmas plans and hurt alot of business.