Coastal surprise headed our way

The Carolinas coast is in for a major rainstorm Wednesday and early Thursday, and some of the computers are "telling" meteorologists that heavy rain could spread far inland -- perhaps as far as Charlotte, or at least the eastern suburbs and counties on the east side of the Queen City.

This is a very complex situation, and if you put five meteorologists in the same room, you might get five different forecasts.

The basics:

1. The cold front that pushed through our region Monday has more or less stalled along the coast.

2. A low pressure system is predicted to form along that front Wednesday and move up the coast.

3. A tropical depression that formed today southwest of Cubs is forecast to move northward, perhaps merging with the low off the Carolinas coast.

That means a lot of rain for the coastal areas, where flood watches have been posted.

But over the past 12 hours, the computer-generated forecasts -- called models -- are pushing the heavy rain farther and farther inland. Some of the models predict the combined low pressure system (the regular low and the tropical low) will actually move northward on an inland route, crossing the coastal plain.

What does that mean for the Charlotte area?

For starters, it means you can kiss the earlier forecast of partly cloudy and cool weather for Wednesday and Thursday good-bye! Instead, look for rain to spread from the coast toward Charlotte during the day Wednesday.

By Wednesday night, heavier rain could be falling in the area.

Some computer models predict the heaviest rain (2 to 3 inches) will stay east of the Chesterfield-Anson-Montgomery county line. Other models bring the heavy rain into the Union County-Matthews-Mint Hill-Cabarrus County area. And forecasters are wondering if the models will push the low pressure system even farther inland -- which means heavier rain will reach Charlotte.

One thing's for sure ... the cut-off between rain and no rain will be very sharp. Wherever that cut-off is, you'll be able to drive 15 or 20 miles between dry conditions and rain.

Check back on Wednesday morning for a better idea of what might happen.