No snow Saturday; next up: Wednesday

The possibility of snow Saturday in the Carolinas' Piedmont has nearly disappeared, and now the focus of attention moves to next Wednesday.

Some snow fans had been hoping a weak disturbance expected to cross the Carolinas on Saturday would imitate the system which brought 2 inches of snow to Charlotte on a Saturday afternoon two weeks ago. But computer models point to a much weaker system.

Temperatures will be very cold for this time of year, but "this time of year" is early March, and average temperatures are 10 degrees warmer than in early January. So even with cold air dominating the eastern United States, the forecast highs Saturday are still in the mid 40s.

Mid 40s and snowflakes don't mix well together.

Actually, precipitation is expected to be very light. Some snow could mix with rain showers in the foothills, but Saturday's system largely will be a non-event.

Keep in mind that the mountains are in an entirely different situation over the next few days. Temperatures are plenty cold enough up there for snowfall, and the northwest flow, coupled with a procession of weak low pressure systems, will bring several inches of snow to the northwest mountains.

So we're left with next week.

That low pressure system is expected to be considerably stronger than anything arriving Saturday. Once again, temperatures will be a few degrees too mild for snow, but that could change -- depending on the track of the low pressure system, its strength, and the location of high pressure over New England (which helps determine how much cold air is funnelled into the Carolinas).

The thinking among most meteorologists is the precipitation will arrive as rain late Tuesday night or Wednesday morning.

Cold air could funnel into the region as the low pressure system begins pulling away. And that could mean a period of snow, even in Charlotte, as the precipitation ends Wednesday morning or afternoon.

4-letter word -- snow -- being mentioned again

I've been mentioning the arrival of much colder air in the Carolinas for the first two weeks of March, but that might not be the only wintry weather in our future.

There are indications from some of the computer models that we could be facing a repeat performance of our Saturday snowfall from a few weeks back.

The cold air is a certainty. After mild weather Wednesday (maybe 60 degrees), colder air will arrive Thursday, and it will get a few degrees colder each day into the weekend.

Once the chill arrives, it doesn't appear to be leaving anytime soon.

The longer-range computer models predict very cold temperatures -- compared to seasonal norms -- next week. That will be followed in the week of March 11-17 by cold (as compared to very cold) weather. The long-range forecasts indicate we won't return to typical March temperatures until after St. Patrick's Day.

Weekend high temperatures, assuming there's sunshine, will be in the middle 40s. That's about 15 degrees below seasonal averages.

So what about snow?

The Global (GFS) model, which sniffed out our little snowstorm a few weeks ago, is predicting a similar system will cross the Carolinas on Saturday. Temperatures will be cold enough for a few inches of snow once again.

Earlier, there were indications of a second storm around the middle of next week, but that system has disappeared off the longer-range forecasts.

Saturday's storm -- if it in fact comes to fruition -- would be another relatively small system. That's four days away, which means there's plenty of time for the track to change. The area of significant snowfall wouldn't be that large, so a change of 100 miles in the storm track could mean the difference of snow or no snow.

Of course, there's also the possibility that the computer models showing no snow this weekend prove to be correct.

One thing is for sure -- the first half of March won't feature the 80-degree days we had last year.

The groundhog was out to lunch

You might remember that the official forecast from Queen Charlotte, the resident groundhog of the region, was for an early spring.

If computer models are correct -- and nearly every forecast model agrees on what's coming over the next two weeks -- the groundhog led us all astray.

It appears as if some very chilly air, at least for this time of year, is headed to the Southeast, and it could dominate our weather for the first half of March. We're not out of the woods from a standpoint of snow, either.

A cold front that will cross the region around the middle of the week will signal a change to cooler conditions.

It appears now as if high temperatures next weekend will be in the upper 40s, with morning lows in the mid 20s. The cold weather will affect nearly all of the eastern United States, and there won't be any escaping it in the Deep South either.  Some of the advance temperature forecasts for places like Jacksonville and Orlando are anything but balmy.

The Climate Prediction Center, operated by the government, is calling for much-below-average temperatures over the next 10 days, with below-average precipitation.

The big question is the storm track. The National Weather Service office in Greer, S.C., says it sees the possibility of mountain snows later this week, and some meteorologists say one or more of the upper-level low pressure systems that will spin around the base of the counter-clockwise atmospheric flow will be strong enough to bring snow at lower elevations.

The European computer model carries the storm systems much farther south, along the Gulf Coast (how about a few flurries in Jacksonville for the opening days of March?), but other models keep the systems farther north.

This much seems certain ... March 2013 won't be anything like March 2012, when temperatures were 10 degrees above average for the month and we had several 80-degree days.

Some stormy days ahead

Don't expect any lengthy dry spells over the next few weeks.

We appear to be entering a stormy period over the eastern United States, and by the time we arrive at mid-March, many of us in the Charlotte region could be the beneficiaries of several inches of rain.

Is there another winter storm lurking out there?  It's impossible to say. There are no signs of a major cold air outbreak, and climatology increasingly makes that difficult. We're rushing headlong toward spring, and average daily temperatures are several degrees warmer than early January.

But the computer models are showing several rounds of storms during the next two weeks.

The first storm system will arrive Friday into early Saturday, and it could bring an ice storm for northern North Carolina and 1 to 2 inches of cold rain for the southern Piedmont.  Temperatures probably will be in the mid to upper 30s Friday while the rain falls in Charlotte, but there could be several hours of freezing rain during the morning to the north of Interstate 40.

Rain intensity could increase overnight Friday.

Then another -- weaker -- storm system will approach Monday.

The computer models keep pointing to a big storm around the beginning of March. That's nine or 10 days away, and the models are notoriously unreliable that far out, especially when it comes to exact storm tracks and temperatures. But that system, should it develop, would be capable of producing a couple more inches of rain.

We've had a couple very dry months of March in recent years, but it's normally one of the wettest months of the year in the Carolinas.

The Climate Prediction Center is calling for very wet conditions in our part of the country over the next 10 days, by the way.

If you're a winter weather fan and want another chance at a big snowstorm, these forecasts of wet and stormy weather should make you happy.  We're not looking at very warm weather over the next two weeks. All it would take is some marginally cold air (i.e., last Saturday) and a strong low pressure system, and frozen precipitation would be a reality.

If your preference is for something like last March -- one of the warmest on record in Charlotte -- it looks as if you'll have to wait until the second half of the month, at the earliest.

Snow Saturday? Some questions, answers

Being a meteorologist or writing about the weather during the winter in the Carolinas is a no-win proposition.

That's due to the really "iffy" situations that are a part of forecasts that involve snow, sleet or ice. Saturday's forecast is one of those situations.

Basically, meteorologists are trying to predict whether or not it will snow, and it's based on a low pressure system that isn't forecast to become strong until it reaches the Carolinas (snow) or goes well off the Atlantic coast (no snow).  And it's based on a forecast over whether it will be cold enough in the atmosphere for snow, and whether it will be cold enough on the ground for anything to stick.

On rare occasions, it's a no-brainer.

Most of the time, it's a close call.  We've had two of those this season.  The first time, little or no snow fell. The second time, the forecast was for sleet and freezing rain, and enough fell to cause problems.

So here are some questions and answers about Saturday's forecast:

It's above 60 degrees today. How can it possibly snow Saturday?

Anyone who's been in the Carolinas for more than a few winters knows the answer to this.  Our winter events often come just a day or two after some very warm weather. It's part of what makes snow-ice forecasts such a "close call." In addition, there also are often 60-degree days a few days after snow or ice. That's especially true from the middle of February through March, when our weather is starting to trend toward spring.

Why do we think it will snow Saturday?

A low pressure system is forecast to move along the Gulf Coast and then cross the Southeast during the day. The latest runs of some computer models indicate the low will strengthen as it pushes across Georgia and the Carolinas. That will increase the amount of precipitation.

At the same time, much colder air is forecast to push into the region overnight and Saturday. Temperatures will be a bit too warm for accumulations, but if the storm system is strong enough, it can bring colder air down from the higher levels of the atmosphere.

Keep in mind, however, that the computer models are waffling all over the place.  One run, they show snow across the North Carolina, especially in the east. The next run, it looks like Georgia and South Carolina get it. We might not know until the last minute, because of the last-minute development of the system. 

Why would it not snow Saturday?

While the Global (GFS) model has been hinting at accumulating snow, the European model has not. It shows very light levels of precipitation, and temperatures that are cold, but above freezing. If the Euro model verifies, then we'll have a mostly cloudy and chilly -- but dry -- day.

When would it snow?

It seems almost certain that precipitation will start as rain in the Charlotte region early Saturday afternoon. As more cold air filters in, the rain would mix with snow, and possibly change to all snow. The mixing would start around mid-afternoon, with snow falling by late afternoon.

The storm system will move quickly, so the snow would end by mid-evening. Temperatures will plummet into the lower 20s Saturday night, so if the streets are wet, we could have black ice Sunday morning.

What is likely to happen?

I've seen this story before, back in January.  The cold air appears to be marginal.  Based on what I'm hearing from meteorologists, the best guess is that Charlotte gets a few snow showers Saturday evening -- enough for conversational purposes, but not enough to cause problems.

The better chance for accumulating snow seems to be east of here.

Stay tuned.

Cold weekend; rain-snow showers Saturday, maybe

After a rather steady dose of generally seasonal temperatures, with a few above-average days, we're in store for a return to winter this weekend.

The strong cold front I wrote about yesterday is still headed for the Carolinas and will cross the region Friday night. The front is expected to be moisture-starved, but there could be a few rain showers Friday evening. Some wet snow could mix with the rain in the foothills, and the higher mountain elevations probably will pick up an inch or two of snow.

Saturday probably will start sunny, cold and breezy.

Highs on Saturday likely won't climb much above the lower 40s.

During the day, an upper-level low pressure system will approach the area from the northwest. That means clouds will increase, and a few showers probably will break out Saturday afternoon and evening.

Harry Gerapetritis, of the National Weather Service office in Greer, S.C., says temperatures Saturday will be above freezing in the Charlotte region. But the air mass covering the Carolinas will be quite cold (below freezing except near the surface), and the precipitation could fall as a rain-snow mix during the afternoon and evening.

With temperatures above freezing, accumulations won't be an issue.  But if you're interested in seeing snowflakes, you might get your wish sometime Saturday afternoon or evening.

Once the upper-level low moves off to the east Saturday night, skies will clear and temperatures will nose-dive. Don't be surprised to see readings in the upper teens Sunday morning, and despite full sunshine, the afternoon highs aren't likely to be much more than about 45 degrees.

The cold snap will be short-lived -- two days.  That means afternoon highs will be back in the lower 50s by Monday.

Incidentally, as we move into the second half of February, our average daily high and low temperatures are climbing. At this time of the year, Charlotte's average highs and lows are 55 and 33. That's about 4 or 5 degrees warmer than at the coldest point, back in early January. By March 1, our average high is 59 degrees, and we reach the 60-degree mark March 5.

Cold, but no snow this weekend

Just wanted to post something quickly, to update the weekend situation.

A few of the computer models earlier this week were hinting at a possible Saturday snowfall in the North Carolina Piedmont, but that has been cleared up.  There will be snow, but only in the mountains (and possibly some flurries in the foothills).

The cold air definitely is coming, though.

A strong cold front will cross the area Friday night, triggering an outbreak of arctic chill that will last about 48 hours.

A couple of weak low pressure systems will cross the Southeast over the weekend, but none of them will be strong enough to cause problems in the Charlotte region. For a snowfall to take place, "phasing" (a merger of storm systems in the northern and southern jet streams) would have been needed.  The computer models are pretty definitive that it will not happen in our region.

The strongest of those low pressure systems will cross to our north late Saturday and early Sunday, and that probably will bring a couple inches of snow in the higher mountain elevations. A few snow showers could spill into the foothills and even the Piedmont along the I-40 corridor, but don't look for anything to accumulate.

The cold air will be noticeable, though.  High temperatures each day probably won't climb above the low 40s.

After that, it looks like a milder trend into next week.

The next storm system figures to develop around the middle of next week, and it could be fairly potent. But as of now, it appears as if temperatures will be in the upper 40s -- too warm for anything frozen.