It's been cold so far this winter season.
I realize winter doesn't officially begin until next week, but tell that to anyone who shivered in 20-degree temperatures last month. In reality, our winter weather arrived in mid-November, with two straight mornings of 21-degree lows.
Since then, it's been more of the same.
The overall average temperatures in November and December have been a bit below average, but that's because we had a couple of very mild days, such as last Friday's mid 70s.
Last year, looking at the period from Nov. 1 through Dec. 12, Charlotte had six days with morning lows in the 20s. All of those came in November, as early December was quite mild. The lowest temperature during that period was 21 degrees.
This year, that same period has produced 14 days in the 20s or colder. It actually dropped to 19 degrees on Nov. 25 and 28, and it was 20 degrees on Tuesday morning this week.
The obvious question is whether this is a sign of things to come in January and February, the heart of winter. Don't bet on it necessarily.
Weather tends to follow patterns that last for several weeks. So, following that theory, it might remain quite cold into January and perhaps beyond.
But remember three winters ago. Temperatures were well below seasonal averages from early December until Valentine's Day. Then, like someone flicked a switch, it got warmer. In fact, the latter part of February and March produced some of the warmest weather Charlotte has seen at that time of year.
Another shot of cold air is looming for Christmas week, so it appears safe to say that December will finish as a chilly month. What happens in January remains a big question mark.
Friday, December 13, 2013
It's been cold so far this winter season.
Thursday, December 12, 2013
The long-range weather computer models are painting a very, very cold picture for Christmas over parts of the United States, but if you believe those advance forecasts, the worst of the cold is headed for the same place that got it the last time -- the Midwest, down to Texas and northern Mexico.
If the models verify, it appears as if the Carolinas would get a glancing shot from the arctic outbreak, much as we did with last week's surge of cold air.
All of this is important, because any storm system that moves into or near this cold arctic air would produce frozen precipitation, and that could be a big deal during the Christmas holidays, with millions of people traveling. If you buy what the models are selling, the risk of snow, sleet and freezing rain would be in places like Texas, Oklahoma, Arkansas, Missouri and possibly western Tennessee.
If you remember, the last arctic outbreak dropped temperatures to what we'd call "chilly" levels here in the Carolinas, and a low pressure system produced a bit of freezing rain last Sunday before temperatures climbed above freezing. Something similar would be possible with a storm system that is forecast to develop around Dec. 26 or 27.
All of this could change, however. And as one professional meteorologist told me Thursday, the winter computer models sometimes tend to exaggerate the amount of cold air in these situations. "When the time comes, temperatures often are not as cold as advertised," he said.
It seems safe to say that we won't be seeing an extended period of mild weather during Christmas week.
Instead, it looks -- for now, at least -- as if we can expect seasonal conditions from this weekend through much of next week, followed by stormy conditions and cool temperatures around Christmas.
Thursday, December 5, 2013
A super-strong arctic high pressure system is blasting its way into the central part of the United States today, helping set the stage for what could be a crippling ice storm in parts of Texas, Oklahoma, Arkansas, Missouri and Tennessee.
Temperatures will struggle to get above freezing Friday in Dallas, and places like Austin and San Antonio will be in the mid 30s for most of the day. Truly frigid weather is predicted for areas farther north.
Often, such arctic air masses push eastward and eventually cover the eastern part of the United States. But not always.
And it appears as if the Southeast might avoid the worst of the powerful cold this time around.
Some of that arctic air mass will seep into the Carolinas this weekend. You'll feel it Saturday, when temperatures tumble from around 60 degrees in the early-morning hours to the lower 40s by evening.
Planning to attend the ACC championship game Saturday night? Bring a heavy coat.
It'll be even worse Sunday, with temperatures near freezing during part of the day and a low pressure system bringing rain. This is when parts of the Charlotte region could experience freezing rain. Right now, it looks as if Charlotte won't see much in the way of glazing. But it could be a different story to the north, in places like Hickory and Statesville -- and especially Boone and other mountain locales.
Then the same cold front that pushes southward on Saturday will retreat northward late Sunday and early Monday as a warm front.
So guess what? On Monday, we're back in the 60s, or at least near 60 degrees. In fact, there will be enough wind shear Monday (winds blowing from different directions at various levels of the atmosphere) that any thunderstorms developing along an approaching cold front could cause wind damage. That front will bring another shot of cold air.
But we won't really get that cold next week, according to the computer models. There probably will be a day or two with highs in the upper 40s, but it will be nothing like the 30-degree highs that cities to the west of us (at the same latitude) experience from the cold air mass.
So that's one system we might avoid.
It's a long winter, though.
We'll keep a close eye on this Sunday freezing rain scenario and let you know about any updates.
Wednesday, December 4, 2013
You'll be hearing a lot in the next few days about a very strong arctic high pressure system that is barreling southward into the United States.
The good news for the Carolinas is that the heart of the cold is taking aim at the Midwest. That will prevent our region from being hit with an ice storm. Unfortunately, residents in the South Central United States might not be so lucky.
The arctic high is bring very cold weather and an amazingly abrupt change in conditions.
An example: Dallas could hit 80 degrees today. Freezing rain and temperatures near 30 degrees are forecast for Friday. The ice storm is expected across north Texas, Oklahoma, Arkansas, western Tennessee and possibly parts of Kentucky.
Earlier this week, the Carolinas seemed to be a possible target of freezing rain. But computer models now indicate not enough of the really cold air will spill across the mountains. It will turn much colder this weekend, but not cold enough for freezing rain.
Instead, we'll deal with our own abrupt temperature change. Forecasters expect highs in the mid 70s Thursday and Friday. By Sunday, when rain is falling for most of the day, temperatures might not get out of the upper 30s.
The changeover day will be Saturday, when temperatures are falling (along with rain). Conditions could be miserable Saturday night for the ACC championship football game at Bank of America Stadium.
Monday, December 2, 2013
While we move through a one-week break from the cold weather, meteorologists and weather geeks will be looking closely at the always-waffling computer models for a hint about what will happen early next week.
The models show a strong cold high pressure system pushing southward from Canada into the United States in a few days. The models also show a low pressure system moving across the South.
That is a scenario for wintry precipitation, and some of the models show freezing rain and some sleet over parts of North Carolina and a few other spots in the Southeast. The time frame for the Carolinas would be late Sunday and Monday.
Regardless of whether it's frozen or not, plenty of precipitation appears to be in our future later this week. Rainfall chances will be increasing gradually every day.
The wintry scenario for the Carolinas depends on a strong cold air damming event to set up. That would mean strong high pressure over the Northeast or eastern Great Lakes, sending cold air on a northeast flow into the Carolinas. At the same time, low pressure would need to follow a track across the Southeast.
Some of the models show that. Others show the high pressure system not being that strong, or the low pressure system tracking up the Ohio Valley instead. If that happens, we would have a cold rain.
In recent winters, a strong high pressure system has established itself off the Southeast coast. That has served to fight off intrusions of cold air and keep conditions relatively mild in the Carolinas.
There are signs of such a ridge of high pressure strengthening in the near future.
If cold air damming looks likely and low pressure seems headed on a southerly track, you'll be hearing more about this ice threat soon.
Monday, November 25, 2013
(UPDATE: I'll be doing a live online chat at 11 a.m.
Wednesday at www.charlotteobserver.com. We'll talk about Thanksgiving
holiday weather and holiday travel. If you want to shoot me some
questions about the upcoming winter, I'll try to deal with those if we
have the time.)
The storm system responsible for the weekend's icy conditions and hundreds of flight delays and cancellations in Texas is moving eastward and still threatening to make a mess of Thanksgiving travel plans.
The Charlotte area will avoid frozen precipitation from this storm, and the rain likely will end by Wednesday morning. But this storm has the potential of fouling up flight schedules along the East Coast. That, of course, has a ripple effect which would be felt in Charlotte.
And regardless of the storm's impact on flight schedules, it will make for nasty traveling conditions Wednesday for people headed north and even east from Charlotte.
Latest indications are that the storm's snow will be limited to inland areas, with the heaviest snow falling in a band from central New York up into Vermont and eastern Ontario and western Quebec. However, several inches of snow are likely in parts of West Virginia and in the western half of Pennsylvania.
Along the Interstate 95 corridor, it looks to be a rain event. The rain could fall heavily at times late Tuesday and Wednesday, which will make for bad driving conditions up I-95 and I-81.
Added to all this will be gusty winds Wednesday.
The impact on air travel is still uncertain. If low visibilities and heavy rain develop Wednesday along the I-95 corridor from Richmond up to Boston, that will cause flight delays. Typically, as the delays build, the impact spreads to locations far from the storm's effects. That is the potential problem Wednesday.
We'll keep close tabs on travel conditions Tuesday and Wednesday.
The good news is that conditions look to be a lot quieter at the end of the weekend, when Thanksgiving travelers are returning home.
Saturday, November 23, 2013
We've had relatively quiet weather for the past several months, since the heavy rain and flooding of June, July and early August came to an end.
Now all that is preparing to change.
It appears as if the eastern United States, including the Carolinas, will be paying attention to weather forecasts for the next several weeks. If you can believe the computer models (and they seem to be relatively consistent on this), you can pack away the shorts. Get the winter coats ready.
It all starts Saturday night and Sunday, of course, with the arrival of some very cold air. High temperatures Sunday probably won't get above the upper 30s in Charlotte, and don't be surprised to see some places in the area with lows around 13 to 15 degrees Monday morning.
Next up will be an old-fashioned Gulf of Mexico winter storm system. We haven't experienced many of these in recent years, but such a critter will develop Monday and push across northern Florida and southern Georgia. If temperatures were a few degrees colder, we'd be looking at a winter storm. Instead, prepare for cold rain, and possibly plenty of it.
After that, the big question is how quickly the storm system departs, and which way it goes from here.
If it's still raining on Wednesday, that will have an impact on Thanksgiving travel for Carolinas residents. Some forecasts indicate the rain could end as snow in higher elevations. That's another bad scenario for travelers.
And will the storm system push out to sea, or go up the East Coast? If it's the latter, then big travel hubs like Washington, Baltimore, Philadelphia, New York and Boston will be getting drenching rain and gusty winds on Wednesday. That won't help the airline schedules.
Once the storm system is gone, things won't change a lot. Cold air will remain.
The longer-range computer models show a big dip in the jet stream, with cold air mass after cold air mass dropping from Alaska and western Canada into the eastern half of the United States. The models differ in predicting whether the heart of the cold air will affect the central U.S. or the East. But it appears nearly certain that there will be cold air around.
Will the southern part of the jet stream remain active, bringing storm systems across the Gulf of Mexico and into the Southeast? That's something to watch. An active southern jet stream added to the cold air is a big deal along the East Coast.
And some of the long-range models show some ridiculously cold temperatures for the Carolinas for the period around Dec. 6-11.
Meteorologists could be kept very busy over the next two or three weeks, at least.