Tuesday, April 30, 2013

Tornado damage repaired ... after 2 years of work

It's taken two years and a lot of hard work, but officials at Great Smoky Mountains National Park have finally finished repairs on two trails damaged by a powerful tornado that ripped through the northwest part of the park.

If you think the really strong tornadoes -- EF-4 and EF-5 -- don't hit the Carolinas, think again. And if you've heard the old tale about tornadoes not hitting mountainous areas, read on.

It was an EF-4, the second-strongest category of tornado, that hit the park April 27, 2011.

It was part of the same system of twisters that created a path of death and destruction in places like Tuscaloosa, Ala. There were no deaths when the storm hit the Great Smoky Mountains park, straddling the North Carolina-Tennessee border, but the twister downed more than 4,500 trees and closed 50 miles of trails.

This week, park officials announced they've finally reopened the Beard Cane and Hatcher Mountain trails. The tornado created two problems for work crews. The first was obvious -- clearing away the thousands of trees that were blown down. But the other job involved repairing collateral damage caused by the twister.

For example, some of the large trees were uprooted, and they caused portions of paths to slid down mountain sides.  Work crews had to rebuild parts of some paths.

"This was some of the most challenging work I have ever faced," said Tobias Miller, supervisor of the Smokies Trail Crew.

In some cases, crews had to rebuild retaining walls on the side of the trails. Workers from parks across the United States were called in to help.

One area will never recover, park officials say. They report that damage at Backcountry Campsite 11 was too significant for repairs, and it will not be reopened.

This is damage at the Beard Cane Trail
in Great Smoky Mountains National Park

Friday, April 26, 2013

Earthquake this morning, not too far away

The western and central Carolinas certainly aren't in an earthquake-prone area, but the ground shook early Friday morning in eastern Georgia, not far from the South Carolina border.

The U.S. Geological Survey said a quake with a 2.8 magnitude was reported shortly before 1:15 a.m. It was centered about 6 miles east-southeast of Lincolnton, Ga.

OK, so you don't know where Lincolnton, Ga., is.  How about 80 miles west of Columbia ... or about 140 miles southwest of Charlotte. Government officials say the quake did no damage but was felt at least 10 miles away.

The same area got a 2.5 earthquake on April 7, according to published reports at the time.

Government scientists as the U.S. Geological Survey say earthquakes happen occasionally in the inland Carolinas area, which also includes eastern Georgia. The strongest, in 1916, had a 5.1 magnitude, which was enough to cause damage.

There also was a 4.2-magnitude quake in eastern Georgia in August 1974.

According to the USGS, faults in the inland Carolinas are deeply buried and mostly undetected. So earthquakes normally are a surprise.

Actually, Charlotte's strongest shake probably came from an earthquake in the other direction -- at the coast. The great Charleston quake, on Aug. 31, 1886, is reported to have caused considerable damage in Charlotte. That quake had a 7.3 magnitude and killed between 60 and 100 people in the Charleston area.

Thursday, April 18, 2013

N.C. State team agrees: Busy hurricane season

Add a North Carolina State University team of scientists to those predicting a busier-than-average hurricane season in the Atlantic basin this year.

N.C. State scientists published their 2013 forecast this week, calling for 13 to 17 named storms in the Atlantic Ocean this year. They also expect three to five named storms in the Gulf of Mexico.

Their forecast total is comparable to that of two other previously announced predictions -- from a Colorado State University team that has been doing this for 30 years; and from WeatherBell's Joe Bastardi, who is well-known to many for his work at Accu-Weather before moving to a different company a few years ago.

The average number of named storms in the Atlantic, Caribbean and Gulf on any given year is 12.

Lead scientist for the N.C. State team is Lian Xie, professor of Marine, Earth and Atmospheric Sciences. He was assisted by three statistics teachers -- Montserrat Fuentes, Derrit Hammerling, and Bin Liu.

The team predicts seven to 10 hurricanes in the Atlantic, with one or two hurricanes in the Gulf.

Scientists expect above-average activity this year because waters in the tropical Atlantic Ocean have warmed, and because there is no El Nino activity forecast for this season. El Nino, a condition of cooler-than-average water temperatures in the eastern Pacific, sends a west-to-east upper-level wind across the southern United States. That atmospheric flow tends to disrupt tropical systems as they try to form.

When I wrote the story a week ago about the Colorado State forecast, I heard from a few readers who said, "What's new? They always forecast above-average hurricane activity?"

To be honest, I agreed initially. But I took a look, and most scientists predicted below-average activity last year. There have been a few other predictions of below-average activity in recent years, although most years' forecasts have been for a lot of activity.

Then again, scientists say we are in a period of above-average hurricane activity.

The government's official forecast, from the National Hurricane Center, will be released in late May.

The season runs from June 1 through Nov. 30.

Tuesday, April 16, 2013

Next 2 days: High humidity, high pollen

All the clouds in the Charlotte region for the past two days are an indication of the relatively high amount of moisture in the air this week.

You can expect three more days of this before a pretty potent cold front brings in some drier and considerably cooler weather for the weekend.

The higher humidity levels are accompanied by high pollen levels.

The rain, gusty winds and lower humidity that arrived last Friday provided the region with three days of relief from tree pollen -- especially oak, ash and birch. But the count was back up Monday and was in the "moderate" stage Tuesday.

The forecast is for very high pollen levels Wednesday and Thursday.

We'll be in humid air that would be downright oppressive if this were summer. In fact, there will be enough humidity in the atmosphere Wednesday for the development of afternoon and evening showers and thunderstorms in the mountains. A few of those showers and storms will spread into the foothills and Piedmont both Wednesday and Thursday, although it will be partly sunny most of the time.

High temperatures likely will climb into the lower 80s both days.

The cold front is expected to arrive Friday, and the timing will make the difference between severe thunderstorms and regular, old garden-variety storms.  As we were reminded last Thursday night and Friday morning, a cold frontal passage during the middle of the night often mutes the strength of thunderstorms.

The latest computer models indicate Friday's front will arrive at night.

And the latest models continue to show a changeover to cooler-than-average temperatures for the weekend, although there's been a bit of improvement in the forecast. On Monday, the National Weather Service was looking at highs Saturday and Sunday for Charlotte in the range of 63 to 65 degrees. Now the forecast is about 3 to 4 degrees warmer.  That could make the difference between jackets and T-shirts for outdoor apparel in the afternoon

Update ... The latest computer models now suggest the cold front will cross the area during daylight hours Friday. But cape levels -- the measurement of buoyancy in the air (lift) -- are rather low. That could limit the development of any severe weather.

We'll watch this over the next few days.

Monday, April 15, 2013

Frosty, chilly weather might not be done with us

I've written a couple times that some fairly cold weather won't be too far away from the Carolinas during the month of April, and it will be possible for the chilly conditions to make a brief return to our region.

That's exactly what will take place, according to the computer models, and I might have been optimistic about the "brief" part of the cold weather's return.

There are indications that a full week of below-average temperatures could be headed to the Charlotte region, starting this weekend. There certainly will be a frost threat for higher elevations, and it's not beyond the realm of possibility that locations fairly close to Charlotte might have to deal with frost on a night or two.

Last Thursday afternoon, I was talking with a relative in northeastern Ohio, who told me it was 38 degrees. At the time, my car thermometers was registering 82 in Charlotte.

From late February into early April, weather across most of the East was dominated by a Greenland block (high pressure) that shunted cold air from Canada and Alaska downward into the United States.  That condition has relented but not disappeared.  The cold air has been contained to our north.

But a strong cold front later this week could open the floodgates for the chilly air to surge south again.

While the National Weather Service is predicting morning lows next Sunday and Monday in the lower and mid 40s for Charlotte, some of the computer models are predicting mid and upper 30s. The 30s are certainly likely for morning lows in areas above 2,500 or 3,000 feet.  By the way, afternoon highs over the weekend will probably be in the range of 63, 63 or 64 degrees in the Charlotte area -- despite full sunshine Saturday afternoon and Sunday.

But a number of the computer models show additional surges of chilly air into the Southeast next week, with another particularly cold period around April 25-27.

Tuesday, April 9, 2013

For first time this year ... on watch for storms

The late arrival of spring weather this year means the South didn't have to endure the outbreaks of severe thunderstorms and tornadoes which have become so painfully familiar in recent years.

Of course, all that is changing now.

Warm weather has finally won out, pushing into all regions of the South. And as a strong cold front moves to the east this week, we're looking at the likelihood of our first significant severe weather outbreak of the season.

It begins today and tonight, in a corridor from Texas northward across Oklahoma, Arkansas, Kansas, Missouri and even southern Iowa.  The Storm Prediction Center in Norman, Okla., has a portion of Oklahoma in the "moderate" risk area, which usually means trouble.  Cities like Austin, Dallas, Oklahoma City, Little Rock and Kansas City will be at risk today and tonight.

On Wednesday, the area of storms pushes eastward into Louisiana, western Tennessee, western Kentucky, the southern two-thirds of Illinois, and western Indiana.

From today into Wednesday evening, damaging wind gusts, large hail and tornadoes will be the big threats.

By Thursday, some of the energy from the storm system along the cold front will push north. That means the storms could be more in the form of squall lines. Those typically don't produce widespread tornado outbreaks and are more likely to trigger damaging wind gusts.

That is likely to happen from Kentucky southward across Tennessee, Georgia, and Alabama.

The Charlotte region is included in the "slight risk" area later Thursday from the Storm Prediction Center, but the real threat will depend a lot on timing.

If the cold front charges through our region late Thursday afternoon or in the evening, the threat of severe weather will be considerably greater than if the front arrives overnight.

I've seen a couple of forecasts recently that indicated the greatest threat of severe weather in April will be to our west -- from Texas across to Kentucky, Tennessee and Georgia.  Our turn, along with Virginia and northern Florida, is expected later in April and in May. But that is just a forecast trend, so take it with a grain of salt.

Looking ahead: The first hurricane forecast of the season from the Colorado State University team formerly headed by Dr. William Gray is due out Wednesday.  We'll report on that.

Friday, April 5, 2013

Winter one day, spring the next

As expected, our weather is making an abrupt shift from winter to spring.

Sometimes there's a period of a week or two for a transition between the two seasons. This year, the transition amounts to a single day -- today.

The storm system that brought rain and unseasonably cold temperatures to the Charlotte region Thursday produced accumulating snow in Virginia and enough sleet to cause road problems in North Carolina's mountains.

Temperatures hovered in the upper 30s for most of the afternoon Thursday, but the change was noticeable Friday. By mid-afternoon, it had reached 60 degrees in Charlotte. And that's just the start. Take a look at forecast highs in coming days:

Saturday ... 65

Sunday ... 70

Monday ... 74

Tuesday ... 77

I'm not saying that we won't have a chilly day before the real heat arrives sometime in May. The pattern in the eastern United States in April and early May will have cold air pocketed in the northern part of the country much of the time. It's conceivable that a renegade cold front could drop south into our region for a day or so.

But it appears, for the most part, that temperatures will remain mild from this point on.  There even could be some 80-degree days during the week of April 15.

We've just come through the coldest March in a decade, and it's about time for some nicer weather.


Wednesday, April 3, 2013

Get the shorts, T-shirts ready

The real start of spring is three days away -- at least here in the Charlotte region.

The atmospheric blocking pattern that made last month one of the coldest March's in several years is losing its punch. The repeated surges of cold air into the Carolinas are on death watch.

The weekend will mark a change to much more enjoyable conditions, and it's possible the nicer weather could continue largely unabated into summer.

It will be almost like flicking a switch on the seasons.

Before we get to that point, there's the little issue of Thursday and Friday.

Throughout the winter, snow-lovers waited for a storm system to move along the Gulf Coast and then up the East Coast.  That would be the recipe for a Carolinas snowstorm, but it never happened.  Now, in the first week of April, with temperatures too warm for snow, such a coast-hugging storm is coming.

If this were January, we'd be buying bread and milk, preparing for a blizzard.  Instead, the system will bring rain and very chilly temperatures Thursday, and the rain will last into Friday morning.

By Saturday, partial clearing will take place, and temperatures are expected to climb into the middle 60s. Many of us will see 70 degrees Sunday, and that will launch a series of days with high temperatures in the upper 60s, the 70s, and possibly even the low 80s.

NOAA's 6-10 day outlook for the Charlotte region calls for above-average temperatures.  So does the 8-14 day outlook ... and the one-month forecast ... and the three-month forecast.

That means it's time to check on the whereabouts of your shorts and T-shirts.

For those of you with relatives up North, this will be an April in which you'll be able to rub it in a bit.  The warming trend will be largely south of the Mason-Dixon line, and although milder weather will surge into the Great Lakes and Northeast at times, there also will be relapses of cold and wet conditions.

So if you want to call a relative on some sunny 75-degree day this month and laugh about their 45 degrees and rain in New York, Pennsylvania, Ohio or Michigan, you'll have a chance.

The other issue is severe weather.

With the cold March temperatures, severe thunderstorms and tornadoes were mostly a non-issue in the South.  The severe weather season is getting off to a late start.  Forecasts I've seen from a number of meteorologists indicate the severe storms will focus on the Mid-South (along both sides of the Mississippi) in April, then spread into eastern Kentucky, eastern Tennessee, the Carolinas and Virginia in May.

Monday, April 1, 2013

What makes I-77 so scary

I wrote in this blog about two years ago on the dangers of driving on Interstate 77 at Fancy Gap Mountain, on the North Carolina-Virginia border.

That danger was brought to life Sunday afternoon, in a huge crash that enveloped nearly 100 vehicles, killed three people, injured 25, and forced the road to be closed for many hours.

It wasn't a first.  That section of road has been the scene of several huge wrecks, and it's really difficult to see how things will change in the future.

Along that stretch of road, I-77's elevation changes from about 1,500 feet in North Carolina to about 2,800 feet at the top, in Virginia. Much of that altitude change happens in a 6.2-mile stretch. It's less scary northbound, because everyone is climbing, and that limits the speed at which most vehicles can drive.

But southbound, from Virginia into North Carolina, is an adventure. As I wrote in 2011, tractor-trailers, other types of trucks, campers, SUVs, minivans and regular sedans tend to fly down that mountain, and they often roll into a thick fog bank that forms on the embankment.

It's actually the Blue Ridge Escarpment, and it's where the North Carolina Piedmont rises into the Appalachian Mountains. That change in topography occurs all along the mountain line in North Carolina, but it's particularly vivid on I-77 because of the high traffic volume and the unusual makeup of the ridge in that area.

Dave Wert, of the National Weather Service office in Blacksburg, Va., said the Blue Ridge line typically is southwest-northeast, but it's on more of an east-west line in the Fancy Gap, Va., area at I-77.

When a moist south or southeast wind from the Atlantic or Gulf of Mexico piles up against the mountain range, it forms dense fog. And when the wind is strong out of the south -- as was the case late Sunday -- it creates a tunnel effect up I-77. Winds can blow at 40 to 50 mph, causing motorists to lose control of their vehicles.

The fog-induced wrecks can be nightmarish. One minute, you're driving south on I-77 in cloudy weather. The next minute, fog limits visibility to a 100 or 200 feet.

The Virginia Department of Transportation did a study on that section of I-77 about a decade ago and found that most of the wrecks happened between mile markers 5 and 7 (Sunday's started near mile marker 6), about halfway down the steep grade. And most happened on the southbound side, where motorists were traveling faster.

So Virginia officials installed devices to measure fog and wind, and to alert motorists in advance with overhead signs. Unfortunately, the warnings sometimes don't slow motorists.

Before this section of road was completed in July 1977, motorists headed from North Carolina to Virginia had to use twisting, turning U.S. 52. A trip of 10 miles could take a couple hours, and portions of that roadway were scary, too.

Nothing can be done about the fog that forms on the mountain and the strong winds that sometimes blow there.  Apparently, nothing can be done about the motorists who charge down the mountain at 75 and 80 mph, seemingly ignoring the electronic signs that warn of dense fog ahead.

It leaves the rest of us at great risk.