Burke paleontologists found the fossil remains of the 66.3-million-year-old dinosaur -- including the 4-foot-long, 2,500-pound skull, as well as lower jaw bones, vertebrae, ribs and teeth -- in the Hell Creek Formation in northern Montana.
The area is world-famous for its fossil dinosaur sites.
A team of more than 45 people helped excavate the T. rex over a month this summer. They first found large fossilized vertebrae that indicated that they belonged to a carnivorous dinosaur.
Before they could excavate the fossils, the team first needed to remove about 20 tons of rock from the hillside, so they could create a ledge at the level of the fossils. The difficult task took a team of eight to 10 people nearly two weeks of continuous digging with jackhammers, axes and shovels.
Once the ledge was in place, they switched to smaller hand tools and uncovered more bones. The skull was found several feet away.
"The combination of the skull features, the size of the bones, and the honeycomb-like appearance of the bones tell us this is a T. rex," said Burke Museum Adjunct Curator of Vertebrate Paleontology and University of Washington associate biology professor Dr. Greg Wilson. "This was a very exciting moment for us."
So far, about 20 percent of a full skeleton has been excavated and scientists say there's likely more to discover.
The T. rex is the first major specimen in Washington.
The skull is one of only 15 reasonably complete T. rex skulls ever discovered.
The massive skull, which is encased in plaster for protection, was moved with a forklift from a flatbed truck to the Burke Museum loading dock.
The public can see the plaster-covered T. rex skull, along with other T. rex fossils and paleontology field tools, in a lobby display at the Burke Museum -- the Washington State Museum of Natural History and Culture -- beginning Saturday, August 20, through Sunday, October 2, 2016.