We have been to Tahoe twice in April. The weather started off glorious both times- clear blue skies and very definitely spring skiing. Very enjoyable until 2pm ish but getting pretty gloppy at the lower levels towards the end of the day. The upside was we came away, went back to where we were staying, rested abit and were playing tennis in t shirts and shorts in the later afternoon.
Both times storms came over when we were there and dumped a load of new snow so we had the benefit of that as well, but it wont be winter skiing as one of the above posts mentions. For that you do, as in Europe need to head high which means probably Colorado.
If you have never been to the States skiing before and are used to the Alps then it is different. The areas are defined by boundaries , there is none of the skiing from one village to the next etc as in Europe. See them as single or multi day tripswhere you go there, ski and come away, unless you are living slopeside.
Tahoe certainly has a number of different areas which cover the whole range of skiing terran and ability levels- as of course does Colorado. At Tahoe the choice is to stay on the North Shore or the South, that decision will largely determine where you ski as staying South and skiing North or vice versa involves possibly more car travel than you would wish. Others may have a different take but my view is a rental car would be essential for there especially in the North which is where we stayed.
Be aware though that Tahoe is on the Calif/Nevada border and Nevada means casinos/gambling/slots. I n some bits it is frankly a bit tacky- not the picturesque Alpine ambiance you might be used to!!
One of the issues we had with Colorado- which i never resolved in my own head- was where to go. Steamboat looked good,but it also looked to be a bitof a drive from there to anywhere else. If youare going from the UK you are probably looking at going for at least a week possibly 10 days. Is there enough skiing there to keep you happy for that time- if not can you go anywhere else easily?
Similarly Aspen- yes you have 4 mountains but 2 of them shut in early April it would seem. Is there enough left to keep you happy.Can you get acheap deal to lessen the pain of the lodging/lift ticket cost-lift tickets in the States are wayyyyy more expensive than Europe (or Canada for that matter)
Then there are the Summit County resorts- quite a few of them but they seem to be the high ones so that might cause a problem with altitude. Like Tahoe you are probably talking aboutgoing to a different resort on a daily basis- by car- and then perhaps going back to 1 or 2 that you really liked.
Utah- as someone suggested- is an option.No direct flights from the UK but you could fly to San Francisco, have a weekend there and thenfly to Salt Lake City which is a hub for Delta Air so loads of flights.You can stay in Salt Lake City, hire a car and have a number of different resorts within a 45 minute drive in good conditions.
Or like me this year you could go to Canada. Vancouver or Calgary are both readily accessible from the UK (direct non stop from London or the major European gateways) and in just about every area it is cheaper than the States, other than possibly airfares.Los Angeles and San Francisco will be cheaper unless you are very unlucky, Denver and Salt Lake City probablyabout the same or they may be a bit less. In my experiencehotels, lift tickets and, especially, eating/drinking is often significantly cheaper in Canada
Also this year, as from Jan1 the US have introduced new rules on airline security and baggage- following 9/11- which may make travelling with skis a bit of a pain, if that is what you plan to do. Nothing which is checked in is to be locked as they scan everything now and if they see something, they want to access the baggage- they will break the lock if they have to so you are told to unlock it all.