Can anyone advise me on planning a trip to Yosemite? I want to find out if late September is still a good time of year to go, or would it be too cold? And are the main sights still open at that point in the year?

Also, if you've been to the area, what are good places to stay that are not within the park itself? Thanks.

It will not be too cold and it's a very popular month for visiting. Most of the waterfalls will have dried up. (Well, the way it's been raining/snowing this year - who knows?) But it will be beautiful with lovely weather. It won't have started to snow yet so everything will still be open.

Fall in Yosemite is magnificent (as are Winter and Spring) -- but it is an entirely different experience than other times. No (or few) waterfalls, but beautiful fall color. And small crowds.

W/ a choice between late Sept and July/August -- I'd choose Sept every time.

But . . . "Also, if you've been to the area, what are good places to stay that are not within the park itself?" . . . Why do you want to stay outside the park? Not only would I stay in the park, I'd stay in Yosemite Valley. In Fall it is much easier to get rooms in the Valley so there is no need to stay outside and spend hours commuting each day.

As the other posters have said, except for the lack of waterfalls, late Sept. is a great time to visit. Far smaller crowds, cool, crisp weather, fall colors and all the roads are usually still open. Some places, such as the Tuolumne Meadows store may be closed, but most will be open. Better late Sept than any time in August.

Our visits to Yosemite are only in September or October. We've always had nice weather, but you do need to be prepared for the drop in temps when the sun goes down. The evenings get cool very fast.

I agree you should look for lodging in the park, preferably in the Valley.

We are going in late September too - our second trip for that time period. Not so crowded, not too cold, no mosquitos and still beautiful

While it usually is not a good time for waterfalls, it may be different this year with the record snowfall.

Really reconsider staying out of the park. There are nice places, but that means a 45 minute to 1 hour drive into the valley. Lodging can be difficult to get at the last minute inside the park, so book now. The two hotels in the valley are Yosemite Lodge [basic] and the Ahwanhee [fancier]. There is also the Wawona, but is not in the valley, but closer to the entrance to the park, so will involve a drive to the valley.

Just a caution if you are camping as we are - there are very few campsites left. We wanted to go the third week of September, but had to go with the fourth week to get a campsite in the valley.

Also, if you are planning to do the Half Dome hike, permits for September went on sale yesterday. Don't know if they are still available or not. But if that is part of your plan, you need to get the permit now.

Not too late. In 2009 we went to Mariposa Grove and the Valley the first week of November. No snow but quite cold.

We went to Yosemite in early October, 2009 and it was perfection both in terms of great weather and thinning of crowds. If you like, click on my name and there is a trip report with photos located about half way through the TR. They should give you an idea of it was like then as far as weather, waterfalls and crowds (or lack thereof).

Permit me to add my first thought when I saw the title of your post:

There is NEVER a bad time to go to Yosemite.

If you can handle Sierra weather (can be cold, and can change VERY drastically and VERY rapidly without much warning), then there is almost no place in the U.S. that would be more beautiful.

I'd rather be freezing in a blizzard in Yosemite Valley in February, than almost any other place I could imagine.