No Chantal, but plenty of water?

Tropical Storm Chantal has confounded the experts this week and done little of what was expected.

Now the question is:  Will Chantal ever have any impact, even indirect, on the Charlotte region?

"That is not a pleasant thought to consider," says John Tomko, of the National Weather Service's office in Greer, S.C.

On Tuesday, Chantal was a feisty little tropical storm with 65 mph winds and an apparent path toward Hispaniola and Cuba.  Forecasters expected the mountains of those two islands to disrupt the storm's circulation, but they thought it would emerge this weekend over the Bahamas as a weak tropical storm.

After that, computer models were pointing Chantal toward the Southeast coast -- possibly South Carolina.

Now all that has changed.  As of mid-afternoon Wednesday, it appears as if Chantal no longer exists as a storm with circulation.  Air Force hurricane-hunting planes have been flying into the storm area for several hours, and there is no real sign of a closed circulation.

It appears as if Chantal is now just a tropical wave.  In the late-morning summary from the National Hurricane Center, meteorologist Lexion Avila said the official forecast is for the system to dissipate by early this weekend.

And, by the way, Chantal won't even cross Hispaniola.  It has taken a more westerly track and will miss the island.

That leaves a lot of questions.  The moisture from Chantal likely will remain somewhere in the Bahamas or possibly the eastern Gulf of Mexico by late this week.

Computer models predict a weakness in the atmosphere that would allow that moisture to stream northward, but the question is whether there is enough moisture left in the remnants, and exactly where that northward track would be.  Would it affect the eastern Carolinas?  Charlotte and the western Carolinas?  Georgia and Tennessee?

We don't know yet, and weak tropical systems are very difficult to predict.

One thing is for sure ... any moisture from a dying tropical system would be bad news for the water-logged western Carolinas.  Areas much farther to the west, where rain is badly needed, would appreciate Chantal's remnants a lot more than we would.

Chantal bears watching in the Carolinas

Mountains and hurricanes are not a good match, and Tropical Storm Chantal appears to be on a collision course with the high country of Hispaniola.


But it is increasingly clear that if some semblance of a tropical storm survives the trek over the Dominican Republic and Haiti in the next few days, Chantal could be a big problem for the Carolinas.

The system's threat isn't high winds and storm surge.  Rather, it could bring heavy rain into an area that doesn't need it.

Early Tuesday afternoon, Chantal's center was about 325 miles southeast of San Juan, Puerto Rico. It was racing to the west-northwest at 29 mph -- the kind of speed that often tears apart a tropical system. Chantal, which had top sustained winds of 65 mph Tuesday afternoon, is expected to hold its own until it reaches Hispaniola later Wednesday.

A hurricane watch is in effect for the Dominican Republic, and tropical storm warnings are posted for Puerto Rico, the Dominican Republic, and the north coast of Haiti. Tropical storm watches are in effect all the way into the Bahamas.

National Hurricane Center specialists and other meteorologists who follow tropical systems aren't sure what sort of storm will emerge from Hispaniola.  The official forecast from the Hurricane Center is for a system with 40 to 45 mph winds to come off the coast.

There will be one other big change.  Chantal will slow down -- a lot.  The high pressure system that is steering the storm now is expected to weaken, allowing Chantal to curve northwestward toward the Bahamas and the Southeast coast.

In fact, by the weekend, Chantal will be crawling.  It is expected to be in the southeast Bahamas on Friday morning and move only to the northwest Bahamas by Sunday morning.

Then what?

The computer models are coming to the conclusion that Chantal will move toward the South Carolina coast, on a northwest track.

A lot of things can happen between now and then ("then" being later Monday or Tuesday), but that track would bring heavy rain into South Carolina and either Georgia or western North Carolina.

By the way ... Another low pressure circulation is emerging from Africa into the eastern Atlantic. Some computer models predict that system will quickly take on tropical characteristics and move westward.  Chantal and the new system are Cape Verde storms, forming in the eastern Atlantic.

It's pretty early in the season for Cape Verde storms, but that might be a sign of what's ahead this hurricane season.

Still wet, but in a different way

After several days of frequent showers and mostly light thundershowers, the weather pattern in the immediate Charlotte area will change over the next few days.

We'll move to a pattern of sunny breaks, mixed with an occasional thunderstorm.  Some of those storms could be strong.

Persistent upper-level low pressure responsible for all the rain in recent days is being shoved westward. That means the steadiest rain will fall over the mountains and in Tennessee and Georgia.

In the Piedmont and parts of the foothills, we'll see a bit more sun. That will allow the atmosphere to become quite unstable, and that also means thunderstorms will be more frequent.

With more sunshine and a destabilized atmosphere, the storms could grow strong to even severe.

But we'll also see periods of sunshine, especially Friday and Saturday. A weak low pressure system might arrive Sunday. That would throw more cloudiness into the mix.  Then it's back to a typical summer pattern next week -- heat, humidity, and a chance of afternoon and evening storms.

Why this strange weather?

The pattern which has been the dominant player in Carolinas' weather this week (and, really, a lot longer) is expected to break down this weekend.

But the real question is whether things really will change for very long.

We're accustomed to seeing weather systems move west to east, or northwest to southeast. This time, the pattern is moving east to west.

Throughout the week, the Carolinas -- and much of the eastern United States -- have been in the combat zone between Bermuda high pressure and a large upper-level low pressure system centered somewhere near the Mississippi River. A third player in the weather has been an old stationary front, stuck across North Carolina.

The Bermuda high's clockwise flow of air and the Mississippi Valley low pressure's counter-clockwise flow met over the eastern United States. That strong southerly flow brought plenty of moisture into the Carolinas. And occasionally, weak low pressure systems moved along the same channel.

All of that combined to create an extended period of unsettled weather.

We've talked a lot about the heavy rain and storm damage. The rain totals actually are amazing, and I'll report on that later this week. But another part of the story has been the temperatures.

A year ago at this time, we experienced three consecutive 104-degree days in Charlotte. This year, our high temperatures have struggled to reach 80 degrees. It's because of the thick cloud cover. Believe me, if the clouds weren't there, we'd be in the upper 80s and low 90s, which is typical for this time of year.

Instead, we're about to experience a very unusual Independence Day in Charlotte.  Our highs probably won't climb above the lower 80s.

Anyways, back to the pattern change.

The Bermuda high is strengthening, and it's pushing the upper-level low farther to the west. As the Bermuda high grows stronger, it's spreading drier air into the Carolinas and along the rest of the East Coast.  Gradually, day by day, larger chunks of the eastern United States are experiencing a decrease in storm activity and an increase in sunshine.

It happened Wednesday on the Carolinas coast.  By Thursday, I expect places like Raleigh and Fayetteville to see the sun for at least part of the day. That pattern reaches Charlotte by Friday.

As that happens, the wettest weather gets pushed westward.  The mountains are in for a soaking Fourth of July, and that pattern will move back into Georgia and Tennessee over the next few days.

My question is:  Will the pattern shift back again?  Will the Carolinas and the rest of the eastern United States find itself back in the atmospheric war zone again soon?

As I've written before, the location and strength of the Bermuda high makes me a bit nervous about hurricane season.  The clockwise flow around the high could serve as a very effective steering mechanism for tropical storms and hurricanes, sending them into the Southeast Coast.

Another 'supermoon' this weekend

We'll experience another of the so-called "supermoon" events this weekend, marking a time when the moon's closest proximity to the earth nearly coincides with the moment when the moon reaches "full" status.

Astronomers actually call this a perigee full moon.  Perigee is the term used for the point each month when the moon is closest to the earth.

The distance at perigee differs a bit from month to month, and the two celestial bodies will be closer than normal this time.

When the moon becomes full, at 7:32 a.m. Sunday in the eastern United States (well after daylight), it will be 221,824 miles from the earth.

What all this means, in effect, is the full moon up there in the sky Saturday and Sunday nights will be closer to the earth than usual. We're not talking about a lot of mileage. It's about 25 to 50 miles closer than many other months.

Of course, tides are a bit higher than normal at full moon, and that will happen this weekend.

Somehow, the term "supermoon" has become the popular term for the perigee full moon.

The biggest of these events comes Nov. 14, 2016, when the earth and moon will be 240 miles closer than they will be this weekend.

Alaska -- the tropical paradise

Some of you weather geeks might know this already, but Alaska is experiencing some amazingly warm weather this week.

High pressure that typically establishes itself over central Canada, and at lower latitudes, has been parked over the Yukon and eastern Alaska for several days. The result has been some true summer weather up there.

Some meteorologists think the Alaskan heat eventually will have an impact on weather in parts of the lower 48 states.  More about that later.

First, here are some numbers from the land of the midnight sun:

Fairbanks has reached 86 degrees or higher for five straight days. It was 88 there Sunday. They've reached 90 degrees a number of times, but an extended streak like this is unusual.

Anchorage got to 81 degrees Tuesday, for its first 80-degree day in four years. Snow fell there a month ago.

Nome hit 86 degrees Wednesday, tying a record for the date. The average high on the west coast of Alaska is 56 at this time of year. Just 13 days ago, Nome had a high of 38 and snow fell.

Barrow, at the northern end of the world, got to 50 degrees Wednesday. The average is 42. The forecast for Thursday is upper 50s, possibly 60.  This is a place that stays well below zero for weeks at a time in the winter.

Juneau, down on the southeast part of the state, had 78 Wednesday.

The little town of Talkeetna, about 80 miles north of Anchorage, recorded 96 degrees Tuesday.

The high pressure system shifted a bit east Thursday, and temperatures are expected to be a few degrees cooler. But the National Weather Service in Fairbanks said Thursday morning that computer models indicate a return to the heat next week.

And I saw a story on Accu-Weather's website in which meteorologist Alex Sosnowski predicted  that the hot air eventually will be pushed southeast, tempered a bit, and affect Canada and the northern part of the United States.

Here's hoping Alaskans remember this heat next January, when it's 40 below zero in Fairbanks.

Derecho or not, last week's storms were nasty

A long-lived outbreak of violent thunderstorms that left millions of people without power last June in the mid-Atlantic introduced the term "derecho" to many people in the United States.

Then came another round of damaging storms last week -- affecting the Charlotte region, along with other parts of the Southeast and mid-Atlantic -- and the "derecho" word is back again.

I've seen some debate in recent days over whether the line of severe thunderstorms that roared across the region last Thursday was actually a derecho.  I don't think there's an official definition for the word, so the debate will continue.

But if we assume a derecho is an hours-long event in which a line or cluster of thunderstorms pushes for hundreds of miles, then our outbreak last week fits the description.

About 200,000 customers in North Carolina lost power in the storms. Some residents of Stanly County didn't get electricity back until Sunday, nearly three full days after hundreds of trees were blown onto roads, homes and power lines.

I got a taste of it.  Our home in Matthews was without power for about 20 hours -- long enough to spoil the food in the refrigerator.

Those storms were a reminder of how many people become fixated on meteorological terminology, rather than dealing with reality.

In hurricane season, some people worry about the location of landfall and the top sustained winds of a system.  They don't concern themselves about the dangers presented by a hurricane or tropical storm after it moves inland.  I've written many times about the problems presented by a dying storm -- the flash flooding, the tornadoes.

It's the same thing with thunderstorms.  Many people worry about tornadoes, dismissing severe thunderstorms as a weak cousin.  But as I've written before, those severe storms can carry winds of up to 100 mph and are capable of causing extensive damage.

Anyways, I pass along links to a couple of things worth looking at.

The Washington Post's Capital Weather Gang is a nice website, although it (understandably) focuses on the mid-Atlantic.  Kathryn Prociv wrote an interesting piece, comparing the 2012 derecho with last week's event.
 
In that article, she reaches the conclusion that the 2013 event was bigger but not as strong.

And I add a link from NOAA's Storm Prediction Center, showing the progress and damage reports from last week's storms.

It'll give you a healthy respect for the power of severe thunderstorms.