However, it isn't a "goodbye" for the 55-year-old meteorologist, as he'll simply be departing his role with providing forecasts for GMA Weekends and will instead focus more of his efforts on doing so over the weekdays. New GMA meteorologist Somara Theodore is officially leading forecasts on the weekends.
Rob contributes frequently to the forecasts on the morning news show GMA as well as to other ABC News reports airing across different times and platforms.
While celebrating the start of his milestone tenth year with the network, Rob alongside an Instagram headshot: "This month marks the start of my 10th year with ABC News, and I couldn't be more pumped to continue this journey with all of you.
"I always dreamed of working for this network as a kid, and my children are equally psyched that I will now be home most weekends!" Rob shares son Mason, five, and daughter Madelynn, 11, with estranged wife Eryn. The two announced last year that they had filed for divorce.
Rob's statement continued: "I'll continue doing what I'm doing, contributing across all shows and platforms Mon-Fri, while getting more quality time with my kiddos.
"My thanks to the bosses who listened and made this work-life balance possible," he added, teasing: "I'm also grateful for an exciting new project with NatGeo that has me exploring some very very cool stuff… more to come!"
His ABC News colleagues shared their support for his new adventure, with Gio Benitez sharing a series of raised hands, and former GMA co-host Cecilia Vega writing: "Yesssssss."
Fellow meteorologist, The Weather Channel's Jim Cantore, commented: "Couldn't happen to a nicer, more talented piezon! Way to go Rob!"
A fan added: "So excited that you can live your dream!" and another also wrote: "Congrats!!! But MISS seeing you in studio with the gang on Weekend GMA!!"
Over the summer, while making appearances across ABC News, Rob has been devoted to spending more time with his two children as they hit big milestones.
June proved to be a big month for the proud dad, as not only did his son Mason turn five years old, but his daughter graduated from elementary school as well.
Alongside photos with his kids and estranged wife, he wrote: "Elementary school is officially in the books and Madelynn is all grow'd up! Well not quite, but she's getting there way too quickly. I'm so proud of her achievements and grateful for the incredible educators."
On Mason's birthday, he shared photos from his celebration at home and lovingly penned: "Evolving from dinosaurs to race cars, Mason's 4th year of life culminated with a Hot Wheels weekend birthday celebration!
"Complete with an epic cousin's cake creation, racetrack tablecloth, pin the wheel on the racecar, dozens of tiny cars, and an overflow of love and gratitude. This now five year old warms the world of everyone within his reach and I’m unspeakably grateful to be his daddy. Bring on Kindergarten!"
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