Will Charlotte get snow Tuesday? Here's the scenario

We've been lucky or unlucky -- depending on whether or not you like snow -- that none of the arctic blasts this month have been accompanied by a storm system.

Outside of the mountains, it's been cold and dry. That's about to change, at least for parts of the Carolinas.

Since late last week, those in the weather-watching world have been paying attention to the computer models as they were updated every six hours, trying to determine if the Southeast would get clobbered with a winter storm Tuesday and early Wednesday.

By early in the weekend, it became more obvious that a disturbance coming from the Pacific onto the West Coast would trek across the country around the same time that another arctic cold front pushes into the Southeast. That would create a winter storm.

On Saturday, it looked like the storm would be suppressed south of the Charlotte region by the strong arctic high pressure system over the Great Lakes. Snow was expected in the Carolinas, but only at the coast. On Sunday, that changed a bit. Some (not all) of the computer models began predicting the storm track would be farther north. In other words, the snow was pushed farther inland.

Officially, it still looks like the snow and will remain southeast of Charlotte. A couple inches are likely in places like Macon, Ga., Athens, Ga., Columbia, Florence and Fayetteville. A mix of ice and snow, with possibly enough ice to cause power outages, was expected in Charleston and possibly Myrtle Beach.

But nobody is firmly in or out of the frozen precipitation area yet.

"The systems that would create such an event are not even in place yet," National Weather Service meteorologist Neil Dixon said Sunday evening. "It will be later (Monday) before we have a better idea."

Dixon said one thing is certain about Charlotte and any precipitation.

"If anything falls in Charlotte, it will be snow," he said. "A lot of times, we have marginal temperatures for snow. But not this time. It will be plenty cold enough."

Temperatures will be in the upper teens and lower 20s Tuesday evening and early Wednesday when the storm system makes its approach to the Carolinas.

Either way, this system figures to bring some frozen precipitation to places that don't often see it.

Some of the places that are included in the vast expanse of the winter storm watch?  How about Houston, New Orleans, Mobile, Pensacola, Macon, Savannah and Charleston?  It was 70 degrees in Houston at 6 p.m. Sunday, yet sleet and freezing rain are expected there in a little more than 24 hours. That's what an arctic cold front followed by a storm system will bring you.

By the way, this arctic blast appears to be the last for a while. Temperatures will modify later in the week, and we'll be near 60 degrees by next weekend. Another big storm system is predicted by the computer models for early in the week of Feb. 3, but that storm would bring rain to the Carolinas, as we'll be well above freezing by then.

When will the cold snap break?

The Carolinas and the rest of the eastern United States are locked in the lengthiest cold snap in several years, with a seemingly endless series of arctic cold fronts sweeping into the Southeast.

The first front in the current cold snap arrived Monday evening. The second is crossing the Carolinas late Thursday. A third front is expected next Monday evening or early Tuesday.

Temperatures will struggle to climb above freezing on Friday, and reaching the average high temperature for this time of year -- 51 degrees -- seems like a far-fetched dream.

We'll all be paying for this in February and March, when our electricity and natural gas bills arrive.

So we ask the question:  How long will this last?

As is typical in the world of meteorology, there is no firm answer.  The computer models waffle from run to run, but we at least know what needs to happen for the cold to relent.

High pressure over the eastern Pacific Ocean and low pressure over eastern Canada have created a jet stream roller-coaster.  Relatively mild air surges north on the back side of high pressure and pushes into Alaska. On the eastern side of the high, arctic air descends from the Yukon into the eastern half of the United States.

A high pressure ridge off the Southeast coast -- know to weather-lovers as the Southeast ridge -- has been squashed in the current pattern.  If the Southeast ridge reappears, our temperatures climb.

A number of computer models are pointing to early February as the time when that might take place.

Like I said ... there's no agreement on this.  Winter-weather lovers take umbrage at the suggestion that the Southeast ridge will reappear.  They believe in the models that keep high pressure parked off the U.S. west coast.  But a number of meteorologists think the pattern will change, possibly as early as 10 days.  That would be sometime around Super Bowl Sunday.

In the meantime, bundle up. And brace yourself for those power bills.

Another polar outburst coming; will this one last?

Remember all that talk about the Polar Vortex?

You'll be hearing about it again, starting next week.

That "polar vortex" term was misused by a lot of people, but it's basically a catch-all term for a deep low pressure system over eastern Canada. The counter-clockwise flow around the vortex sends arctic air masses into the continental United States.

When the vortex is centered closer to the polar region, the cold air doesn't come that far south -- into the far northern part of the United States, for example.

Earlier this month, the vortex dropped farther south. That sent extremely cold air funneling down into the South. And that's what the computer models indicate will happen again next week.

The difference between the upcoming outbreak of cold air and the last one is longevity. It appears, based on the computer models, that the next blast from the arctic will last a lot longer. The last one was a short-lived (two-day) event. The next one could last for a week or more. In fact, some meteorologists predict it will continue through the first week of February (to be followed by milder weather for the rest of the month).

Joe Bastardi, who is well-known in weather circles for his long-range forecasts (and his strong personality), has predicted in recent days that the upcoming blast from the arctic will cause major financial damage over the eastern United States.

It appears as if the cold air will arrive Wednesday in the Carolinas, with high temperatures probably not getting out of the 30s. But there could be even colder weather coming behind that.

A couple other notes:

Super Bowl ... Let's not forget that this year's Super Bowl is scheduled for Feb. 2 in New York. If the next polar outburst continues for a week or so, we face the prospect of watching the big game played in Green Bay-type conditions.  Of course, the NFL said it was ready for such a thing.

Carolinas snow ... Many of the computer models indicate the upcoming cold snap will be mostly dry, and that the southern jet stream, which produces storm systems out of the Gulf of Mexico, will be rather quiet. We'll have to watch that.

You'll be hearing a lot more about this over the next several days.

Wednesday snow in foothills; weekend uncertain

Snow-lovers in the Charlotte region haven't had much to celebrate the past few years, and that's why some who love frozen precipitation are forced to get excited about a couple of longshot events (or maybe non-events) this week in the Carolinas.

Snow is actually rather likely Wednesday evening to the northwest of Charlotte, and there could even be a few flakes falling in Charlotte itself. But barring a huge surprise, there won't be accumulations locally.

"As it stands now, we don't expect any accumulations outside of the foothills," Bryan McAvoy, of the National Weather Service office in Greer, S.C., said Tuesday afternoon.

A cold front will be crossing the area, and a weak low pressure system will be coming along for the ride. Rain showers are expected in the afternoon, but a lot of cold air will be pouring into the region behind the front. That's why the rain is expected to change to snow in the evening. A couple inches are likely in the mountains, and there could be a coating in the foothills.

Wednesday night's cold front will usher in several days of really chilly weather.

Highs are only expected to reach the lower 40s Thursday, and after a minor recovery into the upper 40s Friday, the highs on Saturday might not get out of the 30s.

Then another low pressure system is expected to swing across the Southeast.  The computer models were divided on the subject yesterday and still are today.

"It seems like every run, we get one model that predicts snow, while the two or three others disagree," McAvoy said. "The safest course for now is to forecast snow limited to the mountains."

McAvoy said the timing of the possible system has sped up. On Monday, the computers were predicting precipitation arriving Saturday. Now, McAvoy said, the computers are predicting it Friday night.

Cold returns ... and what will happen Saturday?

Our break from last week's bitterly cold weather will end Tuesday night with the arrival of a fairly strong cold front.

That will put us back in the deep freeze, but it won't be anywhere near as cold as last week. However, our return to chilly weather will be accompanied by a couple of interesting developments.

The first is minor. A weak low pressure system is expected to bring light precipitation to the area Tuesday night and early Wednesday, and some of that could end as a rain-snow mix in the foothills and Piedmont. That would be most likely up along the Interstate 40 corridor, and it would happen around daybreak Wednesday, as the precipitation is coming to an end.

Of more interest is what happens Saturday.

For starters, precipitation is likely. And what else is new?  It has rained on a Saturday or Sunday in Charlotte every weekend since early December.

But the precipitation could fall during some rather chilly weather, and that raises the possibility of snow in the forecast.

The European computer model is bullish on this. These models (basically, computer-outputted forecasts) are run a couple times each day, and the last three runs show snow falling in the Piedmont on Saturday. The National Weather Service office in Greer, S.C., has noted these forecasts and mentioned them in the technical discussion earlier today.

According to the European, a low pressure system would pick up enough Gulf of Mexico moisture as it slides across the Southeast, and temperatures would be cold enough for snow (especially in the northern half of North Carolina).

But as the Weather Service also notes, the European model is alone.

The Global model shows the moisture shunted off to the eastern part of the state.

We'll watch this come into focus over the next few days.

Either way, two things look obvious.  We're returning to colder weather. Our daily high temperatures will be in the 40s, and we might struggle to get out of the 30s on Saturday. Our morning lows will drop into the lower 20s on several mornings.  Once again, this is all relative.  Low 20s sound cold, but that's a world of improvement over last Tuesday morning's 6-degree low in Charlotte.

The other rather obvious part of the forecast.  We're facing yet another wet weekend.

Saturday update on our cold and Sunday's NFL games

The computer models keep coming in colder and colder with the forecasts for Carolinas' temperatures from late Monday into Wednesday.

The National Weather Service now is predicting a low of 9 degrees Tuesday morning and 14 degrees on Wednesday in Charlotte. The Weather Service's meteorologists think temperatures in Charlotte could be below freezing for close to 42 hours, from Monday evening until Wednesday afternoon.

That would be long enough to cause some real problems for area residents' water pipes, and it will pose a real threat to the safety of anyone not protected from the cold.

The forecasts from private meteorological services are similar, but it's likely that temperatures will be down around 5 degrees Tuesday morning in places not far from Charlotte.  That certainly will be the case in the Statesville-Hickory corridor.

Snowfall from the system will be limited to the northwest North Carolina mountains, although some forecasts indicate a dusting is possible in the northwest Piedmont, in the area north of Interstate 40 from Hickory and Lenoir over toward Winston-Salem.

For most of us, it will be a dry outbreak of cold air that could break some records.

Incidentally, some of the forecasts in the North are outrageous.  The Weather Channel is noting that Chicago's record for coldest high temperature, -13 degrees, could be threatened Tuesday.

We'll catch a one-day break Sunday, by the way, with a brief southerly flow sending temperatures into the upper 40s. In fact, it'll stay in the upper 40s Sunday night before the cold front charges through the area Monday. Then temperatures will quickly plummet during the afternoon.

By Wednesday, temperatures will climb above freezing, and we'll be back in the 50s next weekend for the Panthers' home NFL playoff games.

Speaking of NFL playoff games ... Sunday's two contests will be affected by the weather.

The San Diego Chargers play in Cincinnati at 1 p.m., and there's a winter storm warning in effect. It will be raining and in the mid 30s Sunday morning, but the rain will change to heavy snow at some point in the afternoon. Best indications are that will happen sometime in the second half.

And, of course, conditions will be downright Siberian-like in Green Bay, where the Packers will host the San Francisco 49ers.  Temperatures will be around -5 degrees at kickoff, with wind chills down around -20 degrees.

The National Weather Service office in Green Bay has produced an interesting report on some of the coldest games ever played in the NFL.  The meteorologists up there specifically compared the two games generally considered to top the list, when it comes to bad weather -- the 1967 Ice Bowl (Dallas at Green Bay), and the 1982 Freezer Bowl (San Diego at Cincinnati).

Here's a link to that report, and consider yourself fortunate to be in the Carolinas.  It'll be around 55 degrees for the Panthers' game next Sunday, and that seems tropical-like in comparison.

Cold snap could rival January 2003

You'd have to go back to January 2003 to find temperatures as cold as what is forecast for a few days next week in the Carolinas.

There's the typical range among the computer models of exactly how cold it will get, but it appears likely now that Charlotte could drop below freezing sometime Monday evening and not climb above 32 degrees again until Wednesday afternoon.

In some places northwest of Charlotte, like Hickory, Lenoir and Morganton, it could be Thursday before readings climb above freezing.

Below-zero readings are likely in the mountains, and parts of the foothills could be close to zero, if the cold wave verifies.

I checked National Weather Service records in Charlotte, and I only found one day in the last five years when it didn't reach 32 degrees. That was last Jan. 25, when we had a high of 27 degrees and a low of 21, with a trace of snow.

The real comparison with what is expected next week is 10 years ago this month.

In January 2003, Charlotte set two daily records for low temperatures, with readings of 10 degrees on the 18th and 9 degrees on the 23rd. There were actually two waves of cold (somewhat like what could happen this year). The first outbreak was Jan. 17-19, with the coldest day being Jan. 18 (high of 33, low of 10).

The second outbreak was Jan. 23-25, with highs and lows of 38 and 9 on Jan. 23 and 33 and 8 on Jan. 24.

Interestingly, the average temperature that month was 4.4 degrees below average, which is nowhere near being among the 10 coldest Januarys. The average in January 2010 was several degrees colder, but it was spread out across the month.

The computer models seem to agree that next week's cold will be short-lived -- basically, a blast that lasts about 48 to 72 hours before milder conditions return later in the week. In fact, the long-range forecast for the Panthers' home playoff game a week from Sunday is for highs in the low 50s.

Next week could be coldest in at least a decade

The cold air mass pushing into the Carolinas on Thursday night and early Friday will produce some bitter conditions, but it might be just a prelude for an even bigger event early next week.

Computer models insist that a very strong arctic air mass will push into the eastern United States, probably covering the nation -- from the Canadian border to the Gulf of Mexico -- in very cold air.

How cold?

Some of the computer models are shooting out some almost unbelievable numbers. Suffice it to say that we could see high temperatures only in the upper 20s next Tuesday or Wednesday in Charlotte. And that will be despite full sunshine.

Morning lows in single digits are certainly possible in parts of the area, with Wednesday morning looking like the prime candidate for coldest temperatures. In the mountains, we could be looking at daytime highs of 10 to 15 degrees and overnight lows a bit below zero.

This looks to be a dry air mass, however. The only exception to that will be in the northwest mountains, where a flow of unstable air from the northwest will produce a couple inches of snow, probably sometime around Monday night or Tuesday.

In the Piedmont, we're looking at clear conditions.

Once again, however, this looks to be a relatively brief shot of cold air. It will last Tuesday and Wednesday, with warming conditions arriving by Thursday. By Thursday, the center of high pressure will be over the Atlantic, which will put the Carolinas on the back side of the system, receiving a southwest flow. That could allow Gulf of Mexico moisture to stream into the area, and if surface temperatures are still cold enough, we could see a bit of freezing rain early Thursday.

After that, a period of milder weather appears likely into the middle of January.