The Weather Channel has put together some useful information on the cities along the East Coast where Hurricane Irene is likely to hit. They list the cities, estimates of worst conditions, approximate hours with tropical storm force winds and major hazards. 
  
Outer Banks, NC/ Morehead City
Projected timing of worst conditions:through Saturday evening
Approximate hours with Tropical storm force winds: 27 hours
Major Hazards: 5 to 10 inches of rain; Storm surge of 5-9 ft.; Severe beach erosion
 
Norfolk, VA
Projected timing of worst conditions: Saturday morning to late Saturday night
Approximate hours with Tropical storm force winds: 24 hours
Major Hazards:6 to 12 inches of rain
Storm surge of 4-8 ft.
Severe beach erosion
Wind peak 60-80mph
 

Ocean City, MD
Projected timing of worst conditions: Midday Saturday to midday Sunday
Approximate hours with Tropical storm force winds: 24 hours
Major Hazards: 5 to 10 inches of rain
Storm surge of 4-8 ft.
Severe beach erosion
Wind Peak 60-80mph
 

Baltimore, MD
Projected timing of worst conditions: Saturday afternoon to Sunday morning
Approximate hours with Tropical storm force winds: 9 hours
Major Hazards: 6 to 12 inches of rain
Storm surge of 1-3 ft.
Peak winds 45-65mph

 
Philadelphia, PA
Projected timing of worst conditions: Late Saturday afternoon to midday Sunday
Approximate hours with Tropical storm force winds:12 hours
Major Hazards: 6 to 12 inches of rain
Storm surge of 1-3 ft.
Peak wind 45-65mph
 

Atlantic City, NJ
Projected timing of worst conditions: Saturday afternoon to midday Sunday
Approximate hours with Tropical storm force winds:  21 hours
Major Hazards: 5 to 10 inches of rain
Storm surge of 3-7 ft.
Severe beach erosion
Peak wind 55-75mph
 
New York City, NY
Projected timing of worst conditions:Saturday Evening to Sunday evening
Approximate hours with Tropical storm force winds: 21 hours
Major Hazards: 6 to 12 inches of rain
Storm surge of 4-8 ft.
Peak wind 55-75mph
 

Providence, RI 
Projected timing of worst conditions: Late Saturday night to Sunday evening
Approximate hours with Tropical storm force winds: 18 hours
Major Hazards: 3 to 6 inches of rain
Storm surge of 4-7 ft
Peak Wind 40-60mph
 

Boston, MA
Projected timing of worst conditions:Sunday morning through Sunday eve.
Approximate hours with Tropical storm force winds: 18 hours
Major Hazards: 2 to 4 inches of rain
Peak Wind 40-60mph
 

Cape Cod, MA
Projected timing of worst conditions: Sunday morning through Sunday eve.
Approximate hours with Tropical storm force winds: 21 hours
Major Hazards: 2 to 4 inches of rain
Storm surge of 3-6 ft
Peak Wind 40-60 mph
 

Portland, ME
Projected timing of worst conditions: Midday Sunday through Sunday night
Approximate hours with Tropical storm force winds: 12 Hours
Major Hazards: 2 to 4 inches of rain
Storm surge of 1-2 ft.