Now, The New York Times reports, they're back.
Entomologists told the Alabama Cooperative Extension System that milder winters combined with plentiful food allow some colonies to enter spring with much larger numbers.
Entomologist Charles Ray issued his warning in last month's issue of the Alabama Cooperative Extension System, an outreach organization with Alabama A&M University and Auburn University.
Wasp "super nests" - as large as a small auto and containing thousands of insects - are returning to the southern USA, experts warn.
"We have found them attached to home exteriors and other places you might not expect to find yellow jackets", Ray said in a recent ACES release. "So you have the new ones, plus the old workers and double the size of the colony in just one year". If the overture features wasp nests the size of cars growing in your backyard presumably by the time the first act begins we're going to have whole unstoppable streams of Yellow Jackets and hornets flying up our asses and out our mouths, leaving our innards completely liquified in the process.
Giant "super nests" housing up to 15,000 wasps are appearing throughout Alabama, and the sightings may only be beginning.
Yellow jackets will build nests in wall voids, crawl spaces, attics and cracks, as well as in the ground.
"These perennial nests may be several feet wide and have many thousands of workers, far more than an average nest", Ray said.
Ray said he has counted about 15,000 wasps in a single nest. "The nests I have seen this year already have more than 10,000 workers and are expanding rapidly". Experts have warned people to not approach these nests, but immediately get in touch with the appropriate authorities.
Nearly all stinging deaths in the United States are caused by yellow jackets, Hu added.
Next, call a professional for help if the nest needs to be removed.
Ray asked anyone who finds a giant nest to contact him.
Experts advise that only licensed commercial pest control operators remove the massive nests.