@BonesJones my Mom lives in Newport News, VA which is, from what I can tell, the mouth of Chesapeake Bay. You say this could flood DC through the Bay, but DC is like, a 3 hour drive north from Newport News, roughly (i think traffic has a lot to do with this, perhaps not distance idk I've only done it once). If the 'Cane hits the mouth of the bay, or close to it, what do you think about the immediate surrounding areas?
Actually, she lives in Williamsburg witch is inland from Newport News, but not by much at all.
Let talk about the most likely scenario where the hurricane makes landfall in southern North Carolina:
Williamsburg looks pretty protected from storm surge. She's most likely going to be on the north side of the storm so the winds will blow from East to West, and that town seems to be a mile or so from the northeastern coastline which is most likely to experience the storm surge.
Rainfall is a different story. This storm is going to stall, and she'll be in the right front quadrant, which is the usually the strongest and rainiest in any scenario. In this scenario, it'll likely be enforced by the fact that the part of the storm she'll be in will be drawing moisture from off the shore. With all the waterways in that area, flooding could be catastrophic. If she doesn't live on higher ground and she plans on staying, she needs to find a shelter, or put a plan in place in case her house floods out and she needs to get to higher ground. This quadrant is also known to produce the most tornados in its outer bands, and with it stalling for days, she needs to know what to do if a tornado threatens her house. Interior room with no windows that's furthest away from any windows is the best scenario.
If she has big trees, especially on the east side of her house, then that could be a major risk. Also, secure any lose lawn equipment (chairs, tables, etc.) and she should make sure her neighbors do the same. In the case of a tornado or strong wing gusts, you don't want these things turning into projectiles.
However, it is possible the hurricane could move north of the projected path and make landfall in her area.
If the ridge to the north erodes somewhat on the left side, that could lead to a storm that moves up or skirts the coastline. The bad thing about this scenario is that it would be more likely for the hurricane to park itself off the North Carolina/Virginia coast and stall for potentially days while maintaining strength. In this scenario, if it's close enough to the coast she could be experiences tropical-storm/hurricane force winds for who knows how long. It would also increase the flooding potential to Harvey-esqe levels. This is a doomsday scenario and isn't likely, but it's possible.
https://www.wunderground.com/hurricane/atlantic/2018/hurricane-florence?map=model Keep track with Florence here. Lots of updated hurricane models and information.