Today a rathr interesting set up is begining to unfold, which will lead and is already leading to the start of a heavy rain event over the next 48-60 hours
For one, we have Isaacs remnants over te Ohio Valley moving into the eastern seaboard, which s long a stationary front, tropical moisture interacting with this front has led to scattered but heavy downpours over the last 24 hours with many places already seeing 0.50 to as much as 3+ inches in localized areas, as the front comes north and Isaac and his moisture interacts even more with the front, showers and thunderstorms will become more widespread later this afternoon , through tonight into Tuesday, and finally turning into a more steady rain by Tuesday night. We also have a high pressure system east of Maine driving in a stiff ESE wind and some Atlantic moisture.
Over the next hours I expect showers and thunderstorms over the area, at times more widespread than others, not everyone will get dumped on between this afternoon and tomorrow afternoon but anyone who gets stuck under one of these bands will be under it for a long time as the whole set up is very slow-moving and will experience tropical downpours, capable of producing flooding and really racking up rain totals.
As the eventual warm front comes north, and Isaacs circulation comes east, rain will become mor steady, heavy and widespread by Tuesday evening, lasting through Wednesday afternoon with the chance for scattered showers storms remaining through Thursday AM
Total rainfall through the period will be a widespread 1.5-3 inches with localized areas possibly exceeding 4+ inches ON TOP of what ever fell already
HPC total rainfall prediction
GFS total precipitation
After this cold front passes through, it will lead to a great weekend with highs in the mid 70s to around 80 Friday through Sunday lows in the low 50s to low 60s with low humidity, before another cold front comes through early next week with more rain chances and an even bigger drop in temperatures