If you have outside plans for Memorial Day weekend, you might want to have Plan B in place.
All forecast models are hinting at a tropical system developing over southern Florida Tuesday. The storm will then move out over the Gulf of Mexico and tap in to more moisture. Eventually, the storm will make its way onshore along the Gulf Coast.
It appears that the storm will then move north/northwest later in the week. As it does so, it will throw moisture up towards southeast Missouri, southern Illinois, western Kentucky, and northwest Tennessee. It looks like rain could start to move in as early as Friday afternoon.
The European forecast agency's forecast model (ECMWF) positions the center of the storm over central Arkansas by Sunday morning. This will put the area in a position to see continued showers and thunderstorms Saturday, Sunday, and Monday. In fact, one forecast model pumps out 1.3" of rain for Cape Girardeau, Missouri Saturday and Sunday.
If you have outside plans for the holiday weekend, keep an eye on the forecast over the next couple of days and hope things change.