tough question. Could justify a wide range of approaches/predictions. Particularly given your point about wanting it to be a better marathon experience (wise, for sure), I might try (a) getting with a group if possible, whether an official pace group or just people you find early on running around the same pace and effort--take turns leading into wind; (b) try to recapture the mentality from that 3:09 on vacation -- just out for a long run with the group and staying comfortable; (c) if you get to halfway feeling decent and running, say, 7:00 flat pace, you can try gradually picking it up and taking a shot at sub-3:00. If not, you should still be able to back off and get to the finish in one piece with morale intact for next try.
Whatever you do, I hope it goes well. The conditions sound character-building.
DC is no Buffalo for sure, but it's been chilly and windy here this week. Training went fine:
M 1:10
Tu 1:10 with drills/strides
W 1:00 w/ 5 X 3:00 hills (2:00 jog) on treadmill
Th 1:15 + 30:00 x-t
F 1:50 double
Sa 2:20 and back in time to see the end of men's NCAA x-c race -- exciting finish
Su 1:20
Have a great week,
Dave