Friday, December 30, 2011

2011 ... a frightening weather year

The final months of 2011 produced little in the way of weather news, but the tone for this year was set early in the year, and it was not good.

One of the highest tornado death tolls in recent memory and a devastating drought in parts of the South and Southwest were the big stories of the year. But there also were memorable snowstorms in the East, Southeast and Midwest, plus major spring flooding in the Midwest and South.

Summer didn't bring an end to the misery, with a 40-state heat wave in July and a hurricane that produced major flooding in late August.

Five people were killed in November tornadoes in the Carolinas, pushing the twister death toll this year in the country to near 500.

And the news wasn't limited to the continental United States. A storm of epic proportions hit the west coast of Alaska in November.

The year started with a Greenland block -- strong high pressure over Greenland that caused a Negative Arctic Oscillation and brought repeated bouts of cold weather to the East and Midwest. Storm systems formed along the edge of the circulation flow and brought heavy snow to the East.

In mid-February, the Greenland block weakened. With La Nina conditions, the persistent storm track brought several rounds of tornadoes to the South and Midwest.

Summer of 2011 was extremely hot. The storm track moved a bit north, and the result was a very wet season for the eastern Great Lakes and Northeast -- and a very dry summer elsewhere.

The hurricane season was, for the United States, a washout. Only one storm of note affected the country.

I'll recap Charlotte-area 2011 weather later this weekend, but here's a look at the big meteorological stories in the country for the year:

JANUARY SNOW ... A series of snowstorms hit the eastern United States in January. The first brought snow to the Carolinas around Jan. 9, and it moved up the coast. On Jan. 11, every state except Florida had snow on the ground somewhere.

Huntsville, Ala., had snow on the ground for eight straight days, setting a record. New York City and Hartford broke January snowfall records, and South Bend, Ind., set a 24-hour snowfall record with 26 inches on Jan. 8.

At the tail end of the month (actually stretching to Feb. 3) came a Midwest storm. Blizzard conditions, with two feet of snow, were reported in Chicago.

TORNADOES ... The jet stream set up a pattern for storms in April and May, with the track stretching from Texas across Tennessee and Kentucky. That put states from Missouri to the Carolinas in the danger zone for severe weather.

A tornado outbreak in the Carolinas and elsewhere in the Southeast killed 38 people April 14-16, but that was a prelude for the worst of it -- the April 25-28 tornadoes that killed 321 people. Tuscaloosa, Ala., was among the hardest-hit cities. Another outbreak, around May 22-24, included an F5 tornado in Joplin, Mo. The death toll was 177.

Then came the Nov. 16 tornadoes in the Carolinas, with three deaths in Rock Hill and two in Davidson County.

Probably the biggest impact from 2011's tornadoes is a fresh look at the warning system in the United States. A National Weather Service study on the Joplin twister showed that many people did not pay attention to tornado warnings issued by the Weather Service. Emergency management officials will spend 2012 trying to determine why -- and how to change this.

FLOODING ... Extremely heavy rainfall in late April and early May brought record flooding along parts of the Ohio and Mississippi rivers. The area below St. Louis, stretching down to Vicksburg, Miss., was especially hard-hit. But there also was severe flooding during the spring on the Souris River, near Minot, N.D.

JULY HEAT ... Temperatures regularly soared above 100 degrees in much of the South and Southwest, with places like Dallas and Austin shattering records for consecutive 100-degree days. Readings of 100 degrees or more were recorded in Austin and San Antonio as late as the end of September.

At least 40 states reported heat wave conditions. In the Carolinas and other parts of the Southeast, the humidity was a big story. While record heat was not a problem, the high humidity kept temperatures from falling below the mid 70s many nights from late June to mid August.

DROUGHT AND WILDFIRES ... The driest conditions in history were reported across all or parts of Texas, Oklahoma, Arkansas, Louisiana, Kansas, New Mexico, Arizona and Colorado. A lesser area of drought affected a corridor from Mississippi, across Alabama, Georgia and western South Carolina.

As might be expected, wildfires were a huge problem. Fires caused more than $1 billion damage in Texas, New Mexico and Arizona. The Bastrop fire, about 30 miles southeast of Austin, destroyed 1,500 homes and was the worst wildfire in Texas history.

ON THE OTHER HAND ... While part of the country was baking, another part was having a record wet year. Storm systems repeatedly crossed an area from Indiana, over Ohio, Pennsylvania, New York and New England. Then rain from Hurricane Irene added to the mess. The result was several episodes of flooding and some record amounts of precipitation for the year.

Philadelphia had more rain this year (64 1/2 inches) than did Bangkok, Thailand (59 inches).

HURRICANE IRENE ... It was the only hurricane to make landfall in the United States this year, but Irene left its mark. The storm first touched U.S. soil in North Carolina, carving a path slightly inland from the Outer Banks and causing major damage from Morehead City north to the Virginia line.

Irene's approach caused hurricane warnings to be issued for New York City, for the first time in many years. But the system weakened to tropical storm status before making a second U.S. landfall on Long Island. However, heavy rain from Irene's remnants caused massive flooding in Pennsylvania, New Jersey, New York, Connecticut and Vermont. Millions of people were without power for weeks.

ALASKA STORM ... The Bering Sea Superstorm of Nov. 8-9 had low pressure equal to that of a Category 3 hurricane, and it heavily damaged 40 villages and cities along Alaska's west coast. Carrying 100 mph winds, the storm created a 10-foot surge near Nome, and it produced incredible blizzard conditions with heavy snow, gigantic waves, and hurricane-force winds. Advance warning paid off, though, as only one life was claimed by the storm.

Wednesday, December 28, 2011

Cold, snow? Where is it?

Those of you clamoring for cold weather and wintry precipitation -- a group that does not include me -- are suffering through what is, for you, a nightmarish December.

And it's starting to look as if the trend will carry into January.

Temperatures are nearly 6 degrees above average for the month and more than 13 degrees warmer than last December.

The word "snow" hasn't even been mentioned in a Piedmont forecast, and even the North Carolina mountains aren't seeing much frozen precipitation. It's been largely the same way from the eastern Great Lakes to New England.

Our pattern has been consistent -- one or two days of chilly weather, followed by several days of well-above-average temperatures. Fortunately, we've had plenty of rain, so there are no worried about a drought.

This has been classic La Nina conditions.

We had a La Nina last winter, but from early December until mid February, we also had a powerful high pressure system over Greenland that created a "negative" Arctic oscillation and sent very cold air into the eastern United States on a repeated basis.

This year, the Greenland high is not blocking mild air from the Pacific (which is what La Nina produces).

As of now, there are no signs of a different pattern through the first 10 or 11 days of January.

It looks as if we could get our coldest temperatures so far this winter next week. A northwest flow is expected to develop, due to a large trough over the eastern United States.

"It seems cold weather is on the way next week," says Doug Outlaw, of the National Weather Service office in Greer, S.C.

But the really cold air remains bottled up in the arctic, so the "cold" air that funnels down the trough into the Southeast next week won't be brutal. We're talking about a couple of days -- Tuesday and Wednesday, most likely, with highs in the mid to upper 40s and lows in the mid 20s.

Then guess what? The forecast is for a warming trend, from about Jan. 7 to 11. Temperatures could reach 60 degrees again in the second week of January.

As I've written several times already this season ... this pattern could change. A Greenland block could establish itself in late January or anytime in February. But we're apparently going to get through the first half of winter without much of the weather that the cold weather fans really want.

Monday, December 19, 2011

3 storms in next week; snow in the North?

Get ready for a week of unsettled weather across the Charlotte region, with a chance of three separate storm systems affecting the area between now and Christmas.

The last of those low pressure systems could be a snow-maker to parts of the Great Lakes, Mid-Atlantic and New England on Christmas Eve or Christmas Day.

If you're planning holiday travel, you're likely to encounter rain, no matter when you hit the road (or fly) before Christmas.

The situation is difficult to pin down, because the computer models are having a tough time getting the timing right.

But the main thing to remember for the Carolinas is the word "mild." Unlike last year, it will be far too warm for any snowfall. The chilly weather of the past few days will transform into another round of above-average temperatures for much of this week.

High temperatures will be in the 60s from Tuesday through Thursday, and it will remain in the upper 50s Friday and probably Saturday. Sunday is a bit of a question mark, because Christmas could turn out to be a chilly, rainy day.

If you're planning travel, here's the rundown, as of mid-afternoon Monday:

STORM #1: This is the system responsible for the blizzard warnings across parts of the Southwest and southern Plains. This storm will dump heavy snow in that area later Monday and early Tuesday, then make a run northeast. Rain will fall in most areas, for the heavy snow in parts of New Mexico, the Texas panhandle, western Oklahoma, southeast Colorado and western Kansas.

This system will bring moderate rain to the Mississippi and Ohio valley areas and then into the Great Lakes later Tuesday. It will bring showers to the Charlotte region from Tuesday evening into early Wednesday afternoon.

STORM #2: This will be a weaker system, coming out of Texas on Wednesday and crossing the South on Thursday and early Friday. It will produce scattered showers, including a chance of showers Thursday evening and early Friday in the Charlotte region.

STORM #3: This might be the news-maker, because of the snow potential. Some computer models indicate low pressure will swing south from the Rockies, move into Texas and intensify, and then cross the Southeast and swing up the East Coast. If you're traveling Saturday, this system could bring a considerable amount of rain from Georgia up the East Coast.

The highest chance of snow would be in cities like Chicago, Detroit, Cleveland, Pittsburgh and Buffalo, along with much of New York state, much of Massachusetts, western Connecticut, most of Pennsylvania except the Philadelphia area, and extreme western Maryland. The East Coast's big cities would get a cold rain.

If everything develops as indicated, it could mean a rainy Christmas Day in Charlotte -- especially early in the day -- with temperatures only in the 40s.

But some of the computer models are slower with this system, and some show it being weaker.

Tune in again tomorrow.

Wednesday, December 14, 2011

An early look at Christmas travel

Yesterday's blog entry dealt with the chances of snowfall for Christmas in various parts of the eastern United States, but there's another big question for many people ... what will travel conditions be like?

Christmas isn't quite the travel holiday that Thanksgiving is, but millions of people will be flying or driving a significant distance over a period of nearly two weeks.

The computer models have been hinting at the development of a big storm system next week. According to the scenario, the low pressure system would develop over Texas on Monday and then follow a path northeast, into the Great Lakes and then across northern New England. That path would mean accumulating snow in parts of Iowa, western and northern Illinois, Wisconsin, Minnesota, Michigan, New York, Vermont, New Hampshire and Maine. Tuesday and especially Wednesday would be the rough travel days, and the storm would bring heavy rain to parts of the South and the Ohio River valley.

But the computers have been waffling a bit on the forecasts, so this qualifies as an "iffy" situation.

So, for entertainment purposes only (we'll have a much better idea by the weekend), here is the forecast for the week leading up to Christmas, and then a few days afterward.


Monday through Friday, Dec. 23: A mild week, with daytime highs from 60 to the mid 60s. Showers or a steadier rain are possible Tuesday (western Tennessee and Mississippi) and Wednesday (Carolinas, Georgia, eastern Tennessee), and another round of showers is possible on the 23rd.

Christmas Eve: Sunny, with highs in the low 50s.

Christmas Day: Same as Christmas Eve.

Dec. 26-28: Turning colder, with highs in the 40s. Some forecasts hint at rainy conditions on the 27th (the day of the Belk Bowl) or the 28th.


Monday through Friday, Dec. 23: It's a chilly week, but high temperatures are seasonal, in the 40s to near 50 (in places like St. Louis and Cincinnati). Rain spreads across the area Wednesday, and more rain is possible Friday. Snow could fall Friday in places like Milwaukee and Chicago.

Christmas Eve:
A rain-snow mix in the eastern Lakes and near the Ohio River, but snow could fall in places like Detroit and Chicago. High temperatures in the 30s.

Christmas Day:
Turning sunny but cold, with highs in the 20s (north) to mid 30s (south). Snow showers could still be possible in Cleveland, Buffalo and Pittsburgh.

Dec. 26-28: Becoming clear and turning milder, with highs in the 40s by the 28th.

MID-ATLANTIC (New York, Philadelphia, Washington-Baltimore, Boston)

Monday through Friday, Dec. 23: A mild week, with daytime highs in the 40s (Boston) and 50s elsewhere. But rain arrives by the 23rd.

Christmas Eve:
Sunny, with highs in the low 40s (mid to upper 40s in DC and Baltimore).

Christmas Day: Same as Christmas Eve.

Dec. 26-28: Cold on Dec. 26, with rain or a rain-snow mix on the 27th. Then warmer and clearing for the 28th.


Monday through Friday, Dec. 23: A beautiful week, with partly sunny skies and daily highs in the mid and upper 70s.

Christmas Eve:
A cold front brings rain and cooler weather, with highs in the upper 60s.

Christmas Day: Sunny but chilly, with highs in the 60s.

Dec. 26-28:
Becoming warmer, and it could reach the 80s by the 28th.

Tuesday, December 13, 2011

White Christmas chances melting away

Wondering about our chances of having snow for a second consecutive Christmas?

Well, the Fat Lady might not be singing yet, but it doesn't look like "White Christmas" will be in her repertoire for 2011.

A winter storm provided the Charlotte region with a holiday thrill last year, as several inches of snow fell over much of the area -- although much of it fell early on Dec. 26 in Charlotte.

But the pattern that provided us with a brutally cold December and the white Christmas in 2010 is nowhere to be found this time around. That's the reason for our regular stretches of 60-degree-plus temperatures this December.

In fact, many of Carolinas residents who travel up North for the holidays and expect to see snow might view bare ground instead this year.

"Most of the Mid-Atlantic, southern New England, and the Southeast are likely out of the running for a white Christmas," says Alex Sosnowski, a meteorologist with Pennsylvania-based Accu-Weather. "There is too much mild air for snow in those areas."

And if the pattern doesn't change, we might be looking at a very mild winter.

La Nina conditions are present for the second straight year. La Nina (colder-than-average water temperatures in the eastern Pacific) brings mild and dry weather to the South. Cold air and storm systems typically hit the Northwest, upper Midwest, and upper Great Lakes.

Last year, La Nina was overwhelmed by another condition -- the Greenland Block. That is a strong high pressure system over Greenland, and it tends to steer arctic air into the eastern United States and also into Europe. It meant the Arctic Oscillation (AO) was negative, as the upper atmospheric pattern looked like the Thunder Road roller-coaster at Carowinds. The eastern United States was at the bottom of the tracks, and the arctic air tumbled down the tracks from Eskimo country.

"This year, that block is not present," says Scott Krentz, a meteorologist at the National Weather Service office in Greer, S.C. "So La Nina is a major governing factor in our weather."

In addition, a strong subtropical high pressure system is establishing itself over the South. That is keeping cold air far to our north.

How long will this condition last? Sosnowski, Krentz and other meteorologists don't know. Computer models only give us a two-week window into the future, but weather patterns don't tend to change in a hurry.

So it might turn cold in January, but odds of an icy and snowy start to 2012 are lower than they seemed a few weeks ago.

Here are predictions on white Christmas chances for some major cities, courtesy of Accu-Weather:

Probable: Denver, Milwaukee, Minneapolis-St. Paul, near Pittsburgh (especially east), eastern West Virginia, Buffalo, Syracuse, and inland New England.

Doubtful: Chicago, Cleveland, St. Louis, Cincinnati, New York City, Washington, Baltimore, Philadelphia and Boston. (Note: Detroit is between the "Probable" and "Doubtful" categories)

No: Charlotte and everywhere else south of the Mason-Dixon line.

Wednesday, December 7, 2011

Mountains to get a shot of winter

Much chillier air is headed for the Charlotte area, but it's the North Carolina mountains that stand to get a taste of wintry weather over the next 24 hours.

A cold front is crossing the state today, pushing away the mild, moist air that has caused cloudiness and well-above-average temperatures for the last two or three days.

In fact, the unofficial morning low at Charlotte/Douglas International Airport was 61 degrees, which is about 25 degrees below average. The warmest-ever low temperature for this date in Charlotte was 60 degrees, set in 1951. That reading probably won't set a record, though, because temperatures will tumble later today.

However, the mild temperatures are coming to an end. Two areas of rain are crossing the Carolinas today, and the cold front will push eastward of the area by early this afternoon. Temperatures will fall from the low and mid 60s Wednesday morning to the mid 50s by late afternoon. And those readings will tumble all the way to near 30 degrees by daybreak Thursday.

The cooler weather will stay through the weekend, with daily highs in the low to mid 50s, just a couple degrees below seasonal averages.

In the mountains, it'll be a different story.

The rain is forecast to change over to snow by this afternoon, accompanied by winds that might gust to 50 mph. No accumulations are expected in lower areas, like Asheville, but the ridge tops of the southern mountains could get an inch. And up to 4 inches could accumulate in the northern mountains.

Neil Dixon, of the National Weather Service office in Greer, S.C., said the biggest problem might be black ice. Quickly falling temperatures are expected to freeze the rain that falls this morning, and snow on top of the ice could make roads quite dangerous.

"Widespread black ice will create slick conditions on untreated roads, bridges and overpasses," Dixon said.

The low pressure system responsible for our rain and the mountain snow is expected to dump heavy wet snow on parts of West Virginia, western Maryland and Pennsylvania.

Tuesday, December 6, 2011

Gradually, the rain will get here

Anyone who has looked at weather radar for the last 48 hours must have thought a deluge was headed for the Charlotte area.

But it hasn't happened. The area of moderate to heavy rain over the Mid-South has moved very slowly eastward since Monday, but it's about to get a little nudge, and the rain intensity will increase across the Charlotte region soon.

Low pressure is expected to form along the slow-moving cold front and bring the whole system eastward later today and Wednesday.

We'll still remain dry much of the time today, but shower chances will increase considerably tonight. And Wednesday will be rainy much of the time. By the time the rain ends late Wednesday night, much of the area will get about an inch.

Since the growing season is over, many of us haven't been paying attention to rainfall totals, but the precipitation has been arriving at a healthy rate. Since Sept. 1, about a foot of rain has fallen in the Charlotte region. The months of September, October and November can be extremely dry some years, but we've been blessed with ample amounts of rain in autumn 2011. That will help us a lot when the 2012 growing season begins.

As you might expect, our balmy temperatures will go away when the rain ends and the cold front pushes through. In fact, it'll get downright chilly in the Charlotte area from Friday into Sunday, with highs struggling to hit 50 degrees over the weekend. And a couple inches of snow are likely in the mountains.

But there is nothing frigid on the horizon. Looking out two weeks, to around Dec. 19 and 20, the computer models don't show any really cold outbreaks in the Southeast.

The long-range forecasts point to a continuation of what we've been seeing -- brief chilly spells, followed by a warm-up and rain.

Thursday, December 1, 2011

Winter forecast ... an update

Today's the first day of meteorological winter (more about that later), and there are increasing signs that the winter of 2011-12 will be mild across the Southeast -- milder than initially thought.

First, about that "start of winter." I know the official date of winter's start is Dec. 21, but meteorologists believe true seasonal weather is closer to the first days of months. So winter is Dec. 1 to Feb. 28 (or 29); spring is March 1-May 31; summer is June 1-Aug. 31; and autumn is Sept. 1-Nov. 30.

Now, about the new forecast.

Let's go back and review the initial prediction. Forecasters said La Nina conditions in the Pacific would mean mild and dry weather in the South, and cold and snowy conditions in the northwest and parts of the Midwest. However, meteorologists also said that if a strong high pressure system develops over Greenland -- known as the Greenland Block -- it would cause a repeat of last winter.

Last year was a La Nina winter, but the Greenland Block overwhelmed La Nina and sent cold weather -- and a few winter storms -- into the Southeast and up the East Coast.

Forecasters said that they weren't sure if a Greenland Block would develop again this year.

So far, it hasn't. That means December will be milder than originally forecast, meteorologists say. They still aren't sure about January and early February, but they're sticking to their guns about a milder trend for latter February and March.

Accu-Weather, the big private company based in State College, Pa., updated its winter weather forecast today, noting that December will be relatively mild for much of the country.

Accu-Weather thinks the Carolinas will see little frozen precipitation this winter, and I've seen the same forecast from other meteorologists. Brad Panovich, the chief meteorologist at WCNC-TV, the Observer's news partner, has predicted that freezing rain -- not snow -- would be the more likely form of wintry precipitation in the Carolinas.

It would seem that most of our storms will bring cold rain -- or a "close call" between rain and freezing rain.

So here's a summary of the latest prediction for this winter:

CAROLINAS ... Generally, a mild December, with a few brief cold snaps. January is a question mark, and that's when we'd stand our best chance of seeing frozen precipitation. The best guess is that if February starts cold, it will turn mild.

One bad thing ... the current forecast indicates severe thunderstorms and tornadoes again will be a problem in late February and March (and probably into April) across the South.

REST OF THE SOUTH ... Virginia's weather will be a slightly cooler version of ours. Southern parts of Louisiana, Mississippi, Alabama, Georgia, and South Carolina, along with all of Florida, will be mild and dry.

The greatest chance of ice storms (mostly in January) will be in a band from north Texas, across Arkansas, Tennessee, northern Louisiana, northern Mississippi, northern Alabama, north Georgia, and Kentucky.

The severe weather threat will grow in late winter and early spring.

MID-ATLANTIC and NEW ENGLAND ... Not as harsh as last year. There will be a few major winter storms, but it will be nothing like the severe winter of 2010-11.

MIDWEST, GREAT LAKES ... This will be the worst of winter. Cold weather and snowstorms are likely from the Dakotas, across Minnesota, Wisconsin, Iowa, Michigan and northern parts of Illinois, Indiana and Ohio. It could be a nasty winter for Milwaukee, Minneapolis-St. Paul, Chicago, Detroit and Cleveland.

Less-frequent winter storms will impact places like St. Louis, Indianapolis and Cincinnati, where freezing rain or storms with both snow and rain are likely.

The Midwest will be at the heart of the winter storm track.

THE WEST ... The northwest will be colder than average, while the belt from California, across Arizona, Nevada, New Mexico and most of Texas will be mild and dry. That "dry" word is bad for drought-stricken Texas.