Weather in Southern Sweden in September?

No but:

It's about the same latitude as Copenhagen, but has no maritime effect. Figure low 40's to high 50's, periodically windy, often overcast, and plenty of showers.

That's a starter until something better shows up.

I was in Stockholm in late September/early October two years ago. It was on the cool side -- high 50s to around 60. Great temperature for traveling. You could get colder or warmer weather. I would bring a fleece and a waterproof jacket with hood in case it rains. We had a small amount of rain, but you never know.

Thank you--and here I was thinking it was going to still be summer. ;-)

There's no guarantee you'd get summer weather even when traveling to Sweden in the summer! :) I've been there in July and had to wear a fleece. Or it could be 80.

This weather site may come in handy!
You'll love Sweden!

http://www.yr.no/place/Sweden/Kronoberg/V%C3%A4xj%C3%B6/

Go to wunderground.com (weather underground) and choose "trip planner". Put in a location and a date range not more than 2 weeks, you will get the actual weather for those days for the last 12 years or more...high, low, humidity, precipitation, etc.

The location needs to have a weather station, often small towns won't show results, so you may have to try for a larger city in the general area.

Excellent suggestions--thanks everyone! You know, the weather conditions + knowing what you're going to be doing are absolutely crucial for packing lightly. I took WAY too much stuff to China at the end of '08, for example, because I didn't anticipate what the weather was going to do. So I have learned the hard way not to overpack, although I just got back from Edinburgh and Glasgow and my bag was labeled "heavy" in Icelandic as I was returning. I think it was the books... at least, I hope it was the books. ;-) I didn't take too much in the way of clothes, at least I don't think I did.