Scott's Cheap Flights also points out that there are currently incredibly good deals on flights into and out of Bangkok, Kuala Lumpur, Manila, Shanghai, and Singapore from eight major US cities -- Chicago, Denver, Houston, Las Vegas, Los Angeles, New York City, San Francisco, and Washington, D.C. -- for travel between September and April. As of this writing, there are still many standout deals available via Google Flights' multi-city feature in the $400-$500 range ("normal" roundtrip fares for the same time period can exceed $900). That said, airfare is famously unpredictable, so these killer flight prices and the cities they're available to could skyrocket or change at any moment.
However, even if you strike out finding a wildly inexpensive flight to Thailand worth jumping on this time around, don't give up on the "open-jaw" search strategy. Try searching similarly for one-way flights to and from different easily accessible cities around the world and you could end up getting a whole lot more vacation bang for your buck.
h/t Scott's Cheap Flights