Blown Away wrote:11pm: NHC disco says Dorian moving WNW or 300 degrees at 9 knots... Looks like closer to 270 to me?
5pm: NHC had Dorian passing 72W at 0600z... Appears that will happen a little sooner...
Just my observations...

I think, someone can correct me, that the NHC's movement is averaged over 12 hours. I did a real quick Google search and couldn't find anything though.
I haven't calculated the 11pm point, but using best track data at 8pm EDT my model system calculated the following:
6 Hour Average Movement:
Toward the NW or 308° at 8.1 knots (9.3 mph | 15.0 km/h)
12 Hour Average Movement:
Toward the NW or 307° at 9.1 knots (10.5 mph | 16.9 km/h)
24 Hour (1 Day) Average Movement:
Toward the NW or 312° at 9.3 knots (10.7 mph | 17.2 km/h)
48 Hour (2 Day) Average Movement:
Toward the NW or 321° at 9.8 knots (11.3 mph | 18.1 km/h)
120 Hour (5 Day) Average Movement:
Toward the NW or 312° at 10.3 knots (11.9 mph | 19.1 km/h)