I'll start by stating that a LOT can change between now and tomorrow with this forecast, but I'll tell you what we know at this point!
There's a disturbance in the Caribbean that has about a 60% chance of becoming tropical. Either way, it will drift into the Gulf of Mexico and help to drive moisture northward into the southeast. All the while, a cold front will be just south of us, and we'll be hanging out in a cool air wedge (when northeast winds keep temps cooler than normal and cloudy conditions around). Through tonight I don't expect anything other than isolated showers and clouds. Thursday will be cloudy and even cooler than today, with highs in the 60s and 70s. Moisture will increase from the south and that will increase our rain threat for Thursday evening and overnight. Most of the computer models keep rain amounts below 1", but one of the models (NAM) shows some torrential rain for our area overnight Thursday night. It's tough to say, but I'm going with the majority rule on this one. I think we'll get scattered showers and t-storms, but not widespread flooding rain on Thursday night. This could change with further model runs, so it's a good reason to stay up on the forecast.
Friday into Saturday we'll be watching the movement of a system in the gulf. It looks like tropical moisture will stream in, overriding the cool air we have at the surface, and we'll get a steady, moderate rain portions of Friday and Saturday. It's incredibly hard to tell where the heaviest rain will set up. At this point, IF a tropical system develops, it would still be in the gulf. A landfall near New Orleans or Mobile, AL could occur during the weekend, or the storms could hit Mexico/Texas. Regardless, it should bring moisture our was as it travels through gulf waters.
So, let's break it down day by day...
Tonight: A few showers, mostly cloudy, no flood concerns and severe weather chance VERY low.
Thursday: shower coverage will increase through the day, mostly cloudy and cool.
Thursday night: POSSIBLY heavy rainfall, but most likely scattered showers with moderate rain. 0.5-1" of rain likely.
Friday: Off & on rain, cloudy, breezy and cool.
Saturday: Potentially heavy rain, but it could just be scattered showers. Regardless, weekend is looking damp. We just need to brace for the possibility of more flooding if the heavy rain pans out.