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.

Something to watch for the weekend

A two-day outbreak of arctic air is pegged for the Charlotte region this weekend, and anytime there's arctic air in the neighborhood, we're at risk for wintry precipitation.

Typically, there's a dry northwest flow of air during these periods of arctic cold, but every now and then a disturbance in the atmosphere comes through.

Something like that is possible, but not likely, for the weekend.

First, let's set the lineup here.

One of the most popular computer models, the Global (GFS), has been predicting on some of its forecasts in recent days that low pressure will cross the Southeast and intensify off the Carolinas coast. In some of the recent forecasts, the GFS shows accumulating snowfall Saturday in the Interstate 77 corridor.

The European model wants no part of this scenario.  Its forecasts display either no precipitation, or a storm that forms farther out to sea.

Meteorologists are watching all of this carefully, because there's also a chance that low pressure could develop along the coast and move northward, affecting the Middle Atlantic and New England. That area, of course, is still digging out from last weekend's blizzard.

The low pressure system that will be responsible for all of this is not in the continental United States yet. It will be Wednesday before we start getting better data on the system, so there's no need for anything more than a wait-and-see approach for now.

I notice that WCNC meteorologist Brad Panovich is giving Saturday's system a "2" rating (on a 1 to 10 scale) for snow likelihood.  That sounds about right.

Incidentally, Accu-Weather senior meteorologist Alex Sosnowski says that next week, the storm track will move farther northwest of the Carolinas. That indicates milder weather, as we approach the end of February.

Some blizzard left-overs ...

Here are some numbers from last weekend's storm in the Middle Atlantic and New England.

Pennsylvania ... The Keystone State was spared, for the most part.  I noticed a 5.7-inch snowfall total in Allentown, and 4 inches in Philadelphia.

Delaware ... Only a trace in Wilmington, and no coastal flooding problems.

New Jersey ... While Atlantic City got only 1.7 inches, it was a different story to the north. Princeton had 7 inches and Freehold got 8.2.  Up around NYC, there was 11.5 inches in East Rutherford and 10 inches in Newark.

New York ... Some accumulations from around New York City included 11.4 at Central Park; 12.1 at LaGuardia Airport; 6.4 at JFK Airport; and 6.8 at Staten Island.

The heaviest total I saw in Westchester County was 23 inches at Yonkers, with 17.2 at Mount Vernon.

Then there was Long Island ... 33.5 inches at Medford in Suffolk County, and 30.9 inches at the National Weather Service office in Upton. In Nassau County, the high numbers included 18 inches at Massapequa.

Connecticut ... Fairfield had 35 inches, and New Haven recorded 34.3. Other numbers include 27 inches in Hartford and 24 in Bristol (home of ESPN).

Rhode Island ... West Glocester led the way with 27.6 inches, while Providence got 19.5.

Vermont ... Most areas seemed to get 6 to 10 inches, but there was 16.5 in South Royalton (Windsor County) and 14 in Waterbury (Washington County).

New Hampshire ... New Boston was hit with 30.4 inches, and Exeter had 24.1. Farther inland, toward Vermont and the Connecticut River, amounts were closer to a foot.

Maine ... The Portland Jetport got 29.3 inches. Other totals included 26 at Kennebunk and 19.5 at the capital city of Augusta.

Massachusetts ... Framingham was hit with 30.5 inches,  and  28 inches fell at Worcester. Logan International Airport had 21.8 inches.  Winds were ferocious, too. A buoy measured a gust of 83 mph, and there were gusts of 77 mph at Hyannis; 76 mph at Logan Airport; and 75 mph at Bedford.