Update 12 noon CDT via WeatherUnderground:
The latest set of computer models runs from 2am EDT (6Z) this morning push Earl's projected track a little closer to the U.S. East Coast, and we now have two of our six reliable models predicting a U.S. landfall. The latest NOGAPS run shows Earl hitting the Outer Banks of North Carolina late Thursday night, then striking Southeast Massachusetts late Friday night, and Eastern Maine on Saturday morning. The HWRF model predicts a strike on Eastern Maine Saturday morning, but keeps Earl offshore from North Carolina and Massachusetts. None of the other computer models show Earl hitting the U.S., but several models bring Earl within 100 - 200 miles of North Carolina's Outer Banks and Southeast Massachusetts.
Hurricane Earl (update 11 AM) has taken a few small jogs over the last 24 hours and now potentially poses some danger to the eastern seaboard, from the Carolinas to Maine. The most likely forecast still has Earl missing the US east coast and recurving into the North Atlantic. But the storm's westerly track brushes the east coast, meaning residents could feel the brunt of a major hurricane.
On a just completed conference call, NHC director Bill Read said that as of 11 AM EDT Earl is a powerful category 4 storm about 1000 miles from Cape Hatteras, North Carolina. Earl is expected to make a turn toward the northwest or north later today or tonight. The exact location and degree of that turn will determine what areas, if any, on the US east coast are most at risk (FEMA officials are watching that closely). Ideally, Earl moves parallel to or away form the east coast, staying 200 miles away, causing no or minimal damage. There is a small chance Earl causes real problems for the DC region and a slightly larger chance that areas from Cape Cod to Maine see landfall or other storm effects from a weakened Earl. Sea surface temperatures and general conditions are warm enough to sustain a hurricane well north of the DC metro coast. I'll be updating data and other info here throughout the day.
In plain English, for now odds are this system misses the US. But residents from North Carolina to Cap Cod and as far north as Maine should keep an eye on the storm over the next 24 hours and be prepared for high winds, drenching rain, and widespread loss of power, phone service, or water. Those in low laying, coastal, or flood prone regions should be prepared to move to higher ground and know where local storm shelters are located. More info can be found at FEMA and GetReady.gov.
Update: 11:24AM CDT, I'm told latest model puts Earl just a hair west, edging slightly closer to NC and DC.