Friday, September 28, 2012

Will it rain on your weekend game, event?

After two weeks of dry weather, now the rain is coming -- in time for the weekend.

Any rainfall this weekend will threaten high school and college football, along with events like Mint Hill Madness, the Cleveland County Fair, a number of school festivals -- along with the youth sports events and golf outings scheduled.

That's bad news for people planning to spend time outdoors, pitting them against homeowners who have seeded their lawns -- or who are waiting for a little rain before aerating, fertilizing and seeding.

The good news is rainfall will be scattered and periodic. There's a good chance that most areas will get wet sometime this weekend, most likely Friday night or Saturday.  But most of the time will be rain-free.

And if you think it's been a bit too hot for the end of September, you'll like the change in temperatures. Afternoon highs will cool to the upper 70s Saturday and lower 70s Sunday.

A cold front is advancing on the Carolinas, and low pressure will join with the front to bring increased shower and thunderstorm chances to the region. The front is forecast to cross the Charlotte region Saturday, keeping rain chances around.

Originally, forecasters expected rain again Sunday, but the latest computer models indicate the cold front will push far enough south of the area to dry things out.

Be advised, by the way ... a strong low pressure system will form in the Gulf of Mexico on Sunday and move up across the Southeast on Monday and Tuesday. That means steady rain will begin Monday afternoon or evening and continue into Tuesday.  Right now, it looks like 1 to 2 inches of rain will fall in the Charlotte region from that system.

We'll talk more about that later in the weekend.

For now, here's your recreational weather outlook:

HIGH SCHOOL FOOTBALL: There will be showers and thunderstorms moving into the foothills Friday afternoon from the mountains, and a few of those showers and storms will spread into the Piedmont in the evening. The National Weather Service thinks the highest chances of rainfall will be along and north of Interstate 40.

If you're headed to a game tonight, be prepared for a chance of rain. And find shelter quickly if you see lightning or hear thunder.  Those of you with weather apps on your smart phones can watch radar to keep track of any storms.

COLLEGE FOOTBALL: There will be showers throughout the day Saturday, but chances will be highest in the afternoon and evening.  All of the Carolinas will be at risk of rain, but the precipitation will be showery. That means you might get lucky and stay dry.  But take rain gear to the game.  Temperatures will be in the upper 70s in the Charlotte region -- although a bit cooler in the northern part of North Carolina.

SATURDAY MORNING EVENTS: There'll be more clouds than sun, but showers will be widely scattered. Temperatures will be in the low to mid 60s for much of the morning. You'll have a better chance of staying dry in the morning than in the afternoon, according to the most recent computer models.

SUNDAY EVENTS: If you're planning to be outdoors Sunday, rather than indoors watching the Panthers' game in Atlanta, it's looking increasingly like the day will remain mostly dry. It could be cloudy all day, although some sunshine is possible if the front moves far enough south of the Charlotte area. High temperatures probably won't climb much above the lower 70s.

Monday, September 24, 2012

Earliest chill in 6 years ... enjoy it

The temperature in Charlotte is expected to drop into the middle 40s tonight, and you have to go back six eight years to find readings that chilly so early in the season.

Monday morning was our coolest so far in September, with a low of 50 degrees at Charlotte-Douglas International Airport. It got a lot colder elsewhere in the region, including 37 degrees at Boone. There were a few reports of light frost Monday morning in the higher elevations.

Other chilly lows Monday included 37 degrees at Morganton; 43 degrees in Salisbury; 45 degrees in Hickory; 46 degrees in Concord, Rutherfordton and Statesville; and 48 degrees in Albemarle.

Forecasters say Piedmont locations can figure on subtracting another 3 or 4 degrees from those lows Tuesday morning, as the center of a strong high pressure system moves closer to our area. The Piedmont is probably safe from widespread frost, but if you live in a low-lying area that typically gets frost before anyone else, you might want to protect the plants tonight.

Our last reading in the 40s was May 11, when it dropped to 48 degrees.

And the last time it dropped into the 40s this early in the year was 2006, when we had a low of 47 degrees on Sept. 21. Otherwise, the date of the first low in the 40s was about a week later -- Oct. 11 in 2007; Oct. 2 in 2008; Sept. 29 in 2009; Oct. 2 in 2010; and Oct. 1 last year.

Our daytime temperatures Monday are rather chilly, too. The forecast high is 73 degrees, and it's been since June 6 since we had an afternoon that cool.

Nice local weather site: Chris Mullis notes that it dropped to 50.4 degrees Monday morning in Mint Hill, the coldest at his weather station so far this season. It also reached 50 at my station in Matthews.

By the way, Mullis operates a nice website -- -- with all the statistics and hourly reports, a webcam, forecasts, and more.  He's also on Facebook ( with forecasts, current conditions and alerts; and on Twitter ( with hourly conditions and alerts.

This cool-down won't last long. High temperatures will return to the 80s by Wednesday, and we could be in the upper 80s by Thursday or Friday.

Sunday, September 16, 2012

Panthers' game day weather ... and a look ahead

If you're headed to the Panthers' home opener today against the New Orleans Saints, be prepared to get wet.

It's not a 100 percent lock-cinch certainty that you'll get wet today at Bank of America Stadium, but the chances are certainly higher than that of, say, the Cleveland Browns winning the Super Bowl this season.

At 10:30 a.m., there were two clusters of showers near Charlotte.  One area stretched from near University City up to north of Salisbury. That rain won't affect the Panthers' game.

The other cluster of showers covered Cleveland, Gaston and Lincoln counties, and it's moving toward Charlotte.

There's one thing working in the favor of Panthers' fans.  The dome of high pressure which has covered our area for the past week was extremely dry, and the atmosphere became very dry. So it's taking time for the increased moisture to work its way down through the atmosphere to the ground.  That's why we've had only sprinkles over most of the region so far today.

But as the day goes on, the atmosphere will moisten, and rain will be more likely. Those showers to the west of Charlotte would be in the vicinity of Bank of America Stadium well before game time, if they hold together.  As of 10:30 a.m., there's nothing on the radar immediately behind them.

Any rain that falls today will be showery (rather than constant), but it could last for 45 minutes or an hour.  Thunderstorm chances are low, but they're not zero.  Computer models indicate there'll be a bit of instability in the atmosphere Sunday afternoon, so a storm could develop.  But rain showers will be more likely.

The National Weather Service is giving it a 40 percent chance for rain Sunday afternoon.

Looking ahead: The computer models are waffling a bit on this, but they're consistent in predicting a strong low pressure system to form in the Gulf of Mexico and then move northeast on Monday and Tuesday. This is almost like a winter pattern. Those winter Gulf lows are responsible for our snow and ice.

In mid-September, obviously, we'll have rain to worry about.

If the center of the low slides up the Blue Ridge mountains, the Charlotte area could get a couple inches of rain. If the center stays farther west, cutting a path up through western Georgia and central or eastern Tennessee, we'd escape the heavy rain but would be in a severe thunderstorm corridor.

We'll be able to get a better on idea on this late Sunday or Monday.

Friday, September 14, 2012

Weekend outlook: Rain for Panthers game?

A week of glorious, dry weather is about to end with some rain, and the precipitation might arrive in time to dampen the Carolina Panthers' home opener Sunday.

But fans attending high school and college games this weekend are probably safe, and so are the tens of thousands of people planning to visit the Yiasou Greek Festival in Charlotte's Dilworth community or scheduling other outdoor activities Friday and Saturday.

The region has been dry since last Saturday, as cool high pressure has dominated. But a pair of weak cold fronts and a low pressure system will change all that.

A small upper-level low pressure system is crossing the Carolinas on Friday, and that's what is producing the mid- and high-level cloudiness. No rain is expected, however.

So after temperatures reach the lower 80s Friday in the Piedmont, fans attending high school football games this evening will experience partly cloudy skies and temperatures in the 70s at kickoff, possible falling into the upper 60s by late evening. In other words, conditions will be very nice.

If your Saturday plans include golf, tennis or your children's soccer or football games in the morning, there'll be no problems. Temperatures will be in the lower 60s at 7 a.m., climbing rapidly to the mid 70s by late morning and the middle 80s by afternoon.

No rain is predicted for most of the Carolinas, although an approaching cold front could trigger a shower or two in the mountains in the afternoon.

Fans attending college football games Saturday afternoon and evening should remain dry, unless you're in the mountains. Temperatures are expected to remain mild.

Now, about Sunday ...

The Panthers and New Orleans Saints play at 1 p.m.

The weak cold front that moves into the mountains late Saturday is forecast to stall there. A low pressure system then is predicted to slide up the front, bringing showers and even a few thunderstorms.

It looks like the heaviest rain won't fall until Sunday evening and night, but a few showers and storms will be possible in the afternoon.  That means you'd better plan on taking the ponchos.

Don't worry about sunscreen. Forecasters expect a cloudy day, with temperatures reaching the upper 70s in the afternoon.

The early part of next week could be quite wet. Computer models indicate about an inch of rain could fall in the Piedmont and foothills Monday and Tuesday, before clearing and cooler weather returns for Wednesday and Thursday.

Thursday, September 13, 2012

Is summer finished?

The last day of meteorological summer was Aug. 31, and the last official day of summer -- by the calendar -- is next Thursday.

But it's possible the real last day of summer was Saturday, when the temperature reached 90 degrees in Charlotte before strong thunderstorms ushered a cold front through the area.

Now it looks as if real summer weather -- defined as high temperatures in the upper 80s and low 90s, and lows near 70 -- won't return soon.  In fact, it might not return until 2013.

If you look at the overall monthly numbers, the temperature in Charlotte for the first 12 days of the month is 2.4 degrees above average. But that's deceiving. Since Sunday, daily temperatures have been 3.5 degrees below average.  It dropped to 52 degrees Tuesday, the coldest morning since May 12, when it was 50. The low Thursday was 53.

That trend doesn't look to change soon.

We could get into a pattern early next week when overnight lows remain mild (upper 60s), but there's no signs of a return to 90-degree weather.

The Climate Prediction Center is forecasting below-average temperatures for the Charlotte region over the next 8 to 14 days.  By the end of that period, in the final days of September, climatology argues against a return to summer-like conditions.

We're stuck in a pattern of a northwest flow over the eastern United States. That's an awful pattern in winter (except for you snow-lovers), but it's rather nice in September.

We'll review the summer sometime in the next week, but the Charlotte area escaped without too much heat. Granted, we tied the city's all-time heat record on three different days in late June and early July, with highs of 104 degrees.  That alone makes it a summer to remember.

But June wasn't terribly hot, and August was downright tolerable, at least by Carolinas standards.

Wednesday, September 5, 2012

Obama speech change: The trend pointed to this

Back on August 14, I wrote in this blog that while it was impossible to predict the weather that far in advance for President Obama's scheduled Sept. 6 outdoor speech at Bank of America Stadium, the trend this summer was not good.

We've been stuck, with the exception of a few days in early July, in an unsettled weather pattern. Frankly, this has been a very stormy summer in the Charlotte region.

My words on Aug. 14: "But the pattern should concern those who want to party outdoors during the DNC this year."

Before blaming convention organizers for this mess, here are a few things to remember.

First, Democratic National Convention Committee officials couldn't have known about the pattern earlier this year when they picked Charlotte as the convention site. At the time, we were coming off a dry and very mild winter.  Back then, we were probably more worried about drought and 100-degree temperatures.

And those who say, "They should've known it might storm -- this is the South," are only partially right.

Yes, afternoon and evening thunderstorms are common in the Carolinas. But climatology shows that Charlotte has experienced a thunderstorm on Sept. 6 only once in the last 10 years. The thunderstorm pattern tends to weaken in late August and early September, as the autumn pattern of strong high pressure begins taking hold.

The DNC ran into the same thing we encounter in trying to schedule a picnic, a pool party, or any other kind of outing.  With the weather, you never really know.

DNC officials have been communicating regularly this week with the National Weather Service, and the decision to scrub Thursday's outdoor concert-style event at Bank of America Stadium and move it indoors must have been pretty tough.

There's a 40 percent chance of thunderstorms Thursday, and the computer models indicate the storms will have pushed east of Charlotte by evening.  Bottom line:  The decision to move indoors was not made so much because of any weather impact on the President's speech.  It had a lot more to do with worries about a thunderstorm hitting Charlotte in the afternoon, while the crowd was watching the Foo Fighters and Earth, Wind and Fire (they're still together?), and James Taylor.

The idea of lightning bolts zig-zagging into the stadium obviously put a fright into the convention organizers.

And well it should.  North Carolina is among the nation's leaders in lightning-related deaths each year.

The change of venue for Thursday proves yet again what we all know ... it's always about the weather.

Storm chances will extend to Thursday

There hasn't been a lot of mystery surrounding this Democratic National Convention, save for the weather.

And the big unanswered question of the week will remain that way for at least another day.

Will it storm Thursday evening for President Obama's acceptance speech?

Actually, National Weather Service meteorologists feel fairly comfortable that by the time the President speaks, sometime around 10 p.m., any thunderstorms will have moved to the east. There seems to be at least reasonable confidence that the President's speech will go off without a hitch.

But the Bank of America program begins at 1 p.m. A number of live music acts -- including the Foo Fighters, Earth, Wind and Fire, and James Taylor -- are scheduled to perform during the day and evening. And there will be a chance of showers and thunderstorms.

Chris Horne, of the National Weather Service's office in Greer, S.C., says Thursday's forecast remains essentially the same as it has been for a couple days.

Horne says a cold front will push the unstable tropical air -- which has triggered the numerous showers and thunderstorms this week -- off the Carolinas coast.

"There will be less moist air in the atmosphere," Horne says.  That means we won't have to worry about the flood-producing showers and thunderstorms.

However, Horne says, there will be a trade-off.  With the moist air gone, there's a good chance we'll see more sunshine Thursday. Temperatures will be a couple degrees warmer than the 84-degree high Tuesday. That means the atmosphere could become unstable, and that means strong thunderstorms will be a threat.

Translated:  Don't worry about a flood.  Instead, worry about lightning and damaging wind gusts.

Democratic National Convention officials have a back-up plan, to move the outdoor program to Time Warner Cable Arena.  They say it will be a last-minute decision.  The weather will help in that regard.  It almost certainly will be the last minute before we know if strong storms will threaten the stadium.

Tuesday, September 4, 2012

Strongest storms of the day coming through

The strongest thunderstorms so far this Tuesday are rolling across the Charlotte region early this evening, bringing vivid lightning and a threat of flash flooding.

The National Weather Service has issued a Flood Advisory this evening for Mecklenburg County, and other nearby counties -- especially Lancaster, Union and Cabarrus -- could be added to the advisory.

Meteorologists say rain is falling at a rate of 1 to 2 inches per hour. That could cause minor street flooding and possibly some stream flooding in the Center City area, along with UNC Charlotte, Eastland, Matthews and SouthPark.

Basically, everyone east of the airport is in for a gulley washer.

More storms are developing behind these, and it's possible we could see several hours of heavy rain this evening.

No reports of flooding have been received as of 6:30 p.m.

Motorists should be very careful on area roadways over the next hour.

Big question: Where is Tuesday's flooding?

Meteorologists aren't even saying "if," when discussing Tuesday's chances of flash flooding somewhere in the Charlotte region.

The question is "where."

"The abundant moisture virtually guarantees that some locations will receive heavy rainfall," Harry Gerapetritis, of the National Weather Service office in Greer, S.C., said early Tuesday morning. "But the exact location remains in doubt."

The set-up is the same as Monday. The remnants of Hurricane Isaac have settled over the Southeast, turning the atmosphere into a tropical powder keg. The atmosphere is extremely moist, and all it takes is a little daytime heating to create strong thunderstorms.

On Monday, the rainfall bullseye missed Charlotte's uptown, fortunately. The Stanly County city of Albemarle, about 40 miles northeast of Charlotte, was hit hardest. Radar estimates show that more than 4 inches of rain fell in a few hours.

Albemarle police report having to rescue stranded motorists on flooded streets.

Similar heavy rain was reported in eastern Iredell and Davie counties, north of Charlotte.

There is no way to predict where the heavy rain will fall Tuesday.

"It could happen just about anywhere," Chris Horne, also of the Weather Service's office in Greer, said early Tuesday morning. He said the atmosphere will be a bit more stable, which will lessen the chances of severe thunderstorms with damaging wind gusts and large hail.

"But there will be about the same chance of heavy rain," he said. "We're predicting numerous showers and storms as the day goes on."

If anything, the activity might start earlier than Monday, perhaps in the late morning hours.

Gerapetritis says a flash flood watch might be needed somewhere in the Piedmont by later Tuesday morning.

Wednesday looks "about the same as Tuesday," Horne said. "We still think the coverage will be numerous."

Thursday outlook ... Forecasters still think the thunderstorm chances will be lower Thursday than earlier in the week. With President Obama scheduled to speak about 10 p.m. at Bank of America Stadium, and a nine-hour program of live music scheduled before that, the forecast is important.

Horne said thunderstorms will be possible. In fact, the chance of severe weather might be higher Thursday than on Tuesday or Wednesday. But the overall coverage of storms will be less. And by evening, storm chances will decrease.

Translated ... there will be fewer storms, but they could be strong. And the highest chance of storms will be during the daytime portion of the program.

Monday, September 3, 2012

Atmosphere recharging for Tuesday

Sunset has brought an end to the stormy weather which rocked the Charlotte region on Labor Day, and we should be in for a relatively quiet night.

A few showers are possible for the next few hours, but it will be much lighter than the thunderstorm activity responsible for a number of warnings and some reports of flooding during the late-afternoon hours Monday.

The atmosphere remains unstable and very moist, however.  It's simply recharging for Tuesday.

The rainfall total from the storms at Charlotte-Douglas International Airport was about 2/3 of an inch, but much heavier totals were reported elsewhere. There were radar estimates of more than 3 inches of rain falling Sunday afternoon in Albemarle, where streets flooded for about 90 minutes.

Look for more of the same Tuesday, although the showers and thunderstorms might start developing earlier in the day -- perhaps before noon.

I plan to have a new blog entry around 3 a.m. Tuesday.

6:30 p.m. update ... The thunderstorm responsible for the severe weather warning in Charlotte has weakened and moved north of the city.

As I thought, the strongest part of the storm remained west of the uptown area, which was good, considering the large crowds gathered for CarolinaFest.

The urban and small stream advisory remains in effect until 8 p.m. for Mecklenburg and parts of Union, Cabarrus, Lincoln, Gaston and York counties.  Lancaster County is not in the advisory but should be. Up to 2 inches of rain has fallen since 5 p.m. in some of those areas.

At 6:30 p.m., Doppler weather radar showed another line of showers and heavy storms in the Greenville-Spartanburg area.  Like the rotating bands of precipitation in a tropical system, those storms are pinwheeling up toward Charlotte.  It's not clear if the gradual loss of daytime heating will weaken the storms before they get to the Queen City, but we might not be done with the rain tonight.

And as I've been saying ... Tuesday and Wednesday look like repeats of today.  If this heavy rain pattern continues, look for a wide flash flood watch to be issued. The ground is getting saturated in some places.

5:40 p.m. update ... The strong thunderstorms that have battered areas surrounding Charlotte for much of the afternoon are now taking aim at the Queen City.

A Severe Thunderstorm Warning has been issued until 6:15 p.m. for Charlotte.  The National Weather Service says winds of up to 60 mph and 1-inch hail is likely with this storm, so you should seek shelter.

Truth be told, it looks from radar as if the worst of the storm might stay west of the uptown area, but if you're in the big crowd at CarolinaFest, listening to James Taylor, I'd consider seeking a dry and lightning-proof location.

The bigger problem over the next two hours might be flooding. The strong storm moving into Charlotte will be followed by a number of other showers and thunderstorms, and several inches of rain could fall between now and 7:30 p.m.

"Runoff from this excessive rainfall will cause minor flooding ... especially along small streams in the Charlotte metro area," meteorologist Larry Lee, of the National Weather Service office in Greer, S.C., said about 5:20 p.m.

No flooding reports have been received yet from York County, where this storm came from. But very heavy rainfall is being reported down there.  That precipitation is headed for eastern Gaston and Mecklenburg counties.

By the way, we'll be getting more of this again Tuesday and Wednesday.

Earlier post ... Thunderstorms are developing quickly Monday afternoon across the Carolinas, and if you're attending CarolinaFest at the Democratic National Convention or doing anything else outdoors, keep an eye to the sky.

The atmosphere is very unstable and rich with tropical moisture.

Translated: When storms develop this afternoon, they're dropping torrential rain and sometimes causing some wind damage.  The strong winds are a surprise.  We didn't expect that.  The torrential rain is not.

These are the remnants of Hurricane Isaac, and they've settled over our region. Give the atmosphere a little bit of sunshine -- which happened Monday morning -- and you have instant instability.

One strong thunderstorm developed shortly after noon in Union County and trudged slowly into Stanly County, northeast of Charlotte. That storm dropped more than 2 inches of rain in an hour over Albemarle, and a flash flood warning has been issued.

I also see flash flood warnings to the north of Charlotte, where slow-moving storms have developed.

A look at the radar early Monday afternoon shows bright yellows and a few reds -- indicative of strong storms -- blossoming everywhere.  So far, Mecklenburg County has avoided the activity, but that will end eventually.

In fact, at 2 p.m., the radar showed a strong storm to the southwest of Charlotte, in York County, moving toward Mecklenburg County.  If that system holds together, it could affect the uptown area by 3 p.m.

Heat and humidity has been a problem so far Monday for those attending CarolinaFest, and Medic officials held a special news conference shortly after noon, to remind people of the dangers of heat exhaustion. In a word ... drink water.  And if you feel yourself getting dizzy or light-headed, get into shade quickly.

At 2 p.m., it was 90 degrees in Charlotte, with a heat index of 96. That isn't in the heat advisory level, but it's enough to cause problems for people in a big crowd, where there's little air movement.

Eventually, the heat exhaustion concerns will be replaced by thunderstorm worries.  If you're outdoors and the storms approach, seek shelter -- even if James Taylor is about to take the stage. Lightning is a serious threat, and North Carolina is among the national leaders in lightning deaths.

My big concern is flash flooding, and the bad news is that the threat actually might increase Tuesday and Wednesday.  The type of weather we're experiencing today will probably get locked in place for at least the next 48 hours.

Obama speech update ... The forecast for Thursday, for the President's outdoor acceptance speech at Bank of America Stadium, is going downhill.  The latest computer-generated forecasts indicate the Isaac moisture might not be so quick to leave.  Thunderstorm chances have been increased for the day and into the evening.

Monday advice: Pack the umbrella

Whether you're headed to the Labor Day Parade or CarolinaFest in Charlotte's uptown, or if your plans call for a visit to the Matthews Alive festival, there's some simple advice Monday ... bring the umbrella.

We caught a bit of a break in the stormy weather Sunday, when most of the activity was far to the north of Charlotte. Additional thunderstorm activity caused some severe weather over Tennessee and Georgia.

But it looks as if thunderstorm coverage will be widespread Monday and Tuesday.

The good news: The threat of damaging wind gusts and hail will be quite a bit lower both days than on Saturday and Sunday.  We'll be trading the damaging wind for downpours.

"The greater threat will be for locally heavy rain," National Weather Service meteorologist Chris Horne said early Monday morning. "There is a very moist atmosphere."

Harry Gerapetritis, who works with Horne in the Weather Service's Greer (S.C.) office, says there even is a chance for a flash flood watch somewhere in the region Monday. But it will be impossible to issue such a watch until forecasters see exactly where the thunderstorms develop.

The high level of atmospheric moisture and the instability are the fault of Hurricane Isaac. The storm's remnants have drifted into the Carolinas, Virginia and Tennessee and will remain in the region for a few days.

Horne says he expects Monday to develop much like the past two days in Charlotte -- with mostly sunny skies in the morning and early afternoon, giving way to increasing cloudiness and stormy conditions later in the afternoon.  There will be a bit more high cloudiness Monday than on Sunday, so high temperatures probably won't reach the levels (93 degrees) they did Sunday.

That means the Labor Day Parade on Monday morning probably will go off without a hitch, but late-afternoon activities at CarolinaFest and Matthews Alive could be in trouble.  Ditto for the Charlotte Knights' regular-season finale Monday afternoon against the Durham Bulls.

Tuesday forecast ... Horne says "it could be comparable" to Monday.

"There will be little change in the moisture level of the atmosphere," he said.

In short, it means a lot of shower and thunderstorm activity, along with very warm temperatures and hair-curling humidity levels.

And Thursday?  This remains an important forecast, given the Democratic National Convention plans for President Obama to deliver his acceptance speech in an outdoor event at Bank of America Stadium. Meteorologists still think the atmosphere will be drying somewhat Thursday, which will significantly lessen the chances of thunderstorms.  But there will still be a few storms scattered across the region.

Sunday, September 2, 2012

Sunday and Monday could be stormier

Saturday's gully-washer might have been a mere warm-up for what might be in store for the Charlotte area Sunday and Monday.

The Democratic National Convention's outdoor activities stand a chance of falling victim of the weather again.

I've been writing for a couple days about the arrival of moisture from the remnants of Hurricane Isaac, and its presence was obvious in the area Saturday. A cluster of strong thunderstorms dropped torrential rainfall in a few locales.

Gauges measured more than 2 inches on Sunset Road near Beatties Ford Road, and more than 1.5 inches at a gauge at Lebanon Road Elementary near Mint Hill. In Charlotte's uptown area, about 2/3 of an inch fell in an hour. That's not enough for serious flooding, but it caused some minor drainage problems and ruined a lot of people's day.

If anything, the atmosphere is expected to be more unstable Sunday into Monday.

The protesters planning to march in Sunday's parade in uptown might escape the worst of it, because it appears as if the storms will develop in the mid to late afternoon hours. But that's not a guarantee.

"There will probably be a little more storm coverage on Sunday, and the storms will probably be a little stronger," Chris Horne, of the National Weather Service office in Greer, S.C., said early Sunday morning.

He said that in addition for localized flash flooding problems, there also will be the threat of damaging wind gusts and, of course, lightning.

Monday's forecast is important, because the DNC's outdoor festival, CarolinaFest, is scheduled during the afternoon and early evening. Horne says shower and thunderstorm activity will be widespread.

"The coverage will be numerous, especially in the afternoon and evening," he says.

Once again, Horne says, storms will be slow-moving, with heavy rain and the chance of strong winds.

I saw a comment under my Saturday morning blog from a reader who thought I was over-stating the rain threat, based on the National Weather Service's forecast of a quarter-inch of rain or less.  Don't be deceived by that. The forecast is for a large area, and meteorologists say much heavier amounts are possible in localized places that are hit by storms.

Any doubts?  Just ask the people on Sunset Road or Lebanon Road on Saturday afternoon.

Looking ahead, Horne offers hope for DNC officials who want good weather Thursday, when President Obama is scheduled to deliver his acceptance speech at Bank of America Stadium. Several music acts are scheduled to perform before the President appears.

Showers and thunderstorms have been in the Thursday forecast, but Horne said early Sunday that the latest computer models indicate a weak cold front might pass through the Charlotte region that afternoon. By evening, he said, drier air could be working into the area.

"We could see the storm activity really diminish as Thursday wears on," Horne said.

Saturday, September 1, 2012

Heat, not storms are big problem today

We forgot that this was summer, and we were in the South.

After experiencing an August that was downright balmy by Carolinas standards, we're suddenly back in more typical weather for the Labor Day weekend.

We've been talking about the remnants of Hurricane Isaac, and thunderstorms, and all that ... but I think the heat and humidity will be the big story today.

It's a big day for college football, the Matthews Alive parade begins at 10 a.m., and of course, it's the first day of activities for the Democratic National Convention.

Drink plenty of water.

Temperatures likely will soar into the lower 90s today, and don't be surprised to see a few 95-degree readings around. In fact, today could be the hottest day in Charlotte since we had a 96-degree high back on August 2. The dew point temperature, a reading of the humidity, is near 70 degrees, and that's very steamy.

So if you're planning to be outdoors for any length of time Saturday, make sure you stay hydrated.

As for the thunderstorm chances ... they're increasing today. The remnants of Isaac are beginning to curve eastward, from Missouri and Illinois into Indiana and Ohio. As that happens, the moisture will begin to widen southward. Meteorologists don't expect the atmosphere to become very unstable today, but there'll be more instability than Friday.

The bottom line ... there'll be a few thunderstorms by late afternoon and evening, but mostly in the foothills.

Looking ahead to Sunday ... figure on an even higher chance of showers and storms, and the unsettled weather will continue into Monday.

While lightning is always a threat to people who are outdoors, the biggest headache with our stormy weather Sunday and Monday will be heavy rain.  There won't be much of a steering current in the atmosphere, so the storms will be slow-moving.  The moisture content in the atmosphere will be very high. That means heavy rain could fall in a short period of time.

It's even possible to see a few brief flash flooding episodes, especially later Sunday and Monday.