Michael Cavallari's suspected cause of death has been revealed. The brother of former "The Hills" and "Laguna Beach" star Kristin Cavallari was missing for nearly two weeks before police located his body in the Utah desert Thursday. At the time, little was known about his death. 

A report Friday from TMZ suggests that Cavallari, 30, died from exposure to the elements. Law enforcement officials found no signs of trauma and no evidence that he had used drugs or alcohol. His body was found three miles from his abandoned car, which was left running with one airbag deployed in the high desert of Grand County, in eastern Utah. The location is said to be very cold, with temperatures dropping into the teens at night and staying in the 30s for much of the day. 

Kristin Cavallari, 28, recently penned an emotional note to her deceased brother on Instagram. She shared with her 1.6 million followers that her heart was broken after his death. She recalled the many laughs they shared, adding that he "had such a good heart." The mother of three went on to say that while she was struggling to find the words to express her feelings, she knew Michael, who was said to be troubled, was "finally at peace." Fans rallied behind her, liking the photo and sharing messages of love and support with the former reality TV star. 

Prior to her sentimental message, Cavallari released a statement Thursday shortly after learning that her brother had been found dead. She thanked fans for the outpouring of support she and her family had received since going public about Michael's disappearance. She confirmed that police had found his body, but released no other details about his death. Michael Cavallari was last seen Nov. 27 near Green River, Utah. His car was later found abandoned about five miles south of Interstate 70, off Exit 175. His personal belongings, including a cell phone and laptop, were still in the vehicle. 

TMZ reports Cavallari's official cause of death will be determined with a toxicology test.

Michael Cavallari Law enforcement officials do not believe Michael Cavallari, seen above in a photograph provided by the Grand County (Utah) Sheriff's Department, committed suicide. Photo: Grand County Sheriff's Department