After several weeks of inundating rain and flooding across the Northeast region from a southerly tropical flow, another round of heavy rain is on its way for this weekend and early next week. While we won’t have a massive surge of tropical air, we will have a weak disturbance slowly move through, meandering across the Mid-Atlantic and Northeast. This will lead to several days of nasty weather, including heavy rain and scattered thunderstorms, which will give way to additional flash flooding and saturated grounds due to a very wet last few weeks.
Our weak disturbance will begin to gather over Kentucky tomorrow, before expanding out with more showers and storms Friday night and early Saturday. This will bring the first round of showers to the Mid-Atlantic and Northeast. By Sunday, the majority of the region will be dealing with pockets of showers, storms, and heavy rain. The worst of the precipitation will concentrated over southern New England, peaking later on Sunday and Monday. This is when flooding will become the biggest concern. We’re expecting rainfall totals to be as high as 4 or 5 inches before all is done in some locations. That is an incredible number.
While southern New England has seen heavy rain over the last few weeks, the heaviest rainfall totals over the last 3-5 weeks have been concentrated over the northern Mid-Atlantic and central/eastern Pennsylvania. While this disturbance won’t necessarily bring the highest totals to that region, 1-3 inches of rain will cause a fair share of problems. Furthermore, dealing with scattered storms and showers makes it possible for localized higher totals to take place, even over areas where we’re forecasting less than 3 inches of rainfall to occur. It’s plausible to see 3+ inches still across areas that have been consistently inundated by rain over the past few weeks.
Taking a look at the last 30 days of precipitation for the Northeast and Mid-Atlantic region, you can see we have a very widespread area of 10-15+ inches of rainfall. Even with the worst of it covering mostly Maryland and the eastern half of Pennsylvania, widespread totals of 8-10+ inches can still be found across much of southern New England. With 3-5 inches (locally higher) of additional rainfall this weekend and early next week, you can see the cause for concern.
You can see our system moving into the region on Saturday as a disorganized and widespread area of heavy, scattered rain storms. As it slowly moves through, it will continue to drop showers and storms into the region on Wednesday of next week. Not ideal weekend and early week weather.
We’ll continue monitoring this system over the next few days and into next week as our shorter range models get a better handle on how things will shape up. For now, be prepared for more of what we’ve seen over the last 30 days, namely heavy rain, scattered storms, and more flooding.