The latest 1.3 km/4 km high resolution run (and accompanying ensemble) still indicates the potential for catastrophic flooding in the area between Beer-Sheva and Mitzpe Ramon.
Greater than 100 mm of rain should fall generally in this area.
Heavy rain on the mountains east of route 90 should also flood this road as well.
There will be 50 to 100 mm on the mountain tops that drain into the Dead Sea Basin, as well as twenty to fifty mm will fall on the Dead Sea-Basin itself, meaning that river and stream flows should also be quite strong in this area as well.
Here is a link to a similar event of the past, although here the center of the heavy rain will be further north than occurred then.