A long duration, heavy rain event has become increasingly likely for the Washington region Friday through Saturday night, possibly lingering into early Sunday. Several inches of rain could fall and areas of flooding could develop. It will probably not rain continuously and some areas will get hit harder than others. But anyone with outdoor plans Friday afternoon through Saturday evening should begin thinking about a Plan B. This is a very unusual storm system to develop

in late July — in some ways resembling a winter Nor’easter. But because it is the middle of summer and the air is much more humid, this storm system will be able to generate significantly more precipitation than a winter storm. Some models predict pockets of 6 to 7 inches of rain. (This is the equivalent of 60 to 70 inches of snow but winter storms in Washington won’t ever produce this much snow because not as much moisture is available when temperatures are colder.) READ MORE