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.