Bad Information Warning:

I have seen local news websites linking to a SLOSH simulation of worst case scenario storm surges on the Chesapeake Bay based on a hurricane coming strait up the Bay. This study was done after Isabel and is not anything like what you will see with Irene on the Chesapeake Bay. Repeat, this is not what will happen with Irene.

The track of Irene is too far east and the track of Irene has already taken it over land, reducing the surge "drag" that accumulates over time. Irene will have major storm surges along the Atlantic coast including Norfolk, very southern Chesapeake Bay, much of the Delaware Bay, northern New Jersey, New York City, and Long Island. It will not have a major storm surge on the majority of the Chesapeake bay, and in fact the latest models I am watching show a negative surge in the northern bay due to winds pushing water south.

Please refer to the surge probability diagrams produced by the NHC:
http://www.nhc.noaa.gov/psurgegraphics_at4.shtml?gm

You can also use the NWS coastal Operational Forecast System models that include tide simulations:
http://tidesandcurrents.noaa.gov/models.html