I seem to remember it's the East winds to watch out for in the harbour but check which way its facing the sea comes straight in from one direction.
Take a dinghy cos the taxi's not too reliable.
Other than that its a great place. Hire a car for about £19 including fuel. Mind you it takes only an hour or so to drive right round.
Anything over an easterly 3 and you in the poo in Braye Harbour. Also if you use your own duck take an outboard because it will probably be too far to row. I have always found the water taxi spot on if a tad expensive with a large crew. Hire bikes not a car, a car will make your tour like teenage sex, all over in a few seconds, and about as enjoyable. A bike tour is great fun.
Have a great sail. Two weeks ago the water taxi was good and reliable, the duty-free (Alderney is not in the EU) dhingy was doing a roaring trade and you can hire bikes just by Crabby beach. But if the wind has any North in it and the nightime forecast is any greater than F3 or perhaps F4 you will roll like hell all night and it will be more comfortable in Cherbourg. F5 and above and I would definitely go to Cherbourg. See you there!
If the wind from N to E does catch you out and you are rolling badly, provided you have searoom, attach an additional warp to the buoy from the stern. Then adjust the two lines until you are lying head to wind & swell - much more comfortable. Be very careful that you have enough searoom as you will be lying heading in a different direction from the rest, until they catch on! The lines might need some adjustment if the wind changes direction
For a first crossing I would recomend you make for Cherbourg not Alderney for a number of reasons:
1/ In prevailing SW winds you are more likely to have to beat to Alderney than Cherbourg, often Cherbourg will be a much easier sail.
2/ By crossing the lanes closer to a right angle it is much easier to work out whether you are on a collision course with shipping, as the angle increases it becomes much more difficult. Cherbourg is an easy entrance at any time and in most conditions.
3/ The leading marks at Alderney are difficult to see the first time. After a first time crossing you are more likely to be tired and stressed and to make a mistake in the entrance here would be a disaster.
3/ Bars and restaurants fill up quickly in the season, you can easily not get fed until 10 if you have not booked, not what you want after a long crossing. In Cherbourg there is never a problem getting fed and watered as long as you get away from the 'tourist ' restaurants
4/ As previous posts have mentioned in any NE wind Alderney is very rolly, be sure to take a length of chain to connect to the mooring buoy - we got through two 1" warps in one afternoon last tear
5/ The passage from Cherbourg to Alderney is a comfortable largely sheltered on. Even in a SW you are largely in the lee of high land and with a big tide under you progress is rapid.
If you are not already a member, you hould consider joining the Westerly Owners Association, they have two rallies crossing this summer and some of those going will be crossing for the first time. Details are on www.westerly-owners.co.uk
Wherever you go, have a great passage - you will never forget the feeling of arriving after your first time over.