Massive European sale...many airlines and many destinations

So I've been itching to get back to Europe since my first trip there earlier this year in March. However, tickets have been so expensive usually ranging in the $1,000-$1,400 range just for a round trip economy ticket from my home airport in Indianapolis (IND). But it appears there is a massive fare war going on between multiple airlines all across the US to Europe for dates in August 2016-March 2017 (excluding the holidays in December). Flights are going for a mere $600-$700 which is almost half the price they normally do but I'm not sure how long these fares are going to last.

Southwest offering sale for flights as low as $69 one way

I've noticed Southwest doesn't get too much attention in the travel blogs except when it comes to their coveted Companion Pass but they can they still be a good option in many cases. As I mentioned in a previous post, they are one of only 2 options for me to fly non-stop from my home airport in Indianapolis (IND) to Las Vegas (LAS) which I frequent often and the other choice is the budget airline Allegiant so in reality its my only option for non-stop flights. They also have some pretty generous policies such as their cancellation policy which allows you to cancel your flight for no charge and they are the last of the legacy carriers to offer not one but TWO free checked bags.