Fairfax County schools superintendent Jack D. Dale will not return to work before his official retirement on June 30 as he continues to recover from emergency cardiovascular surgery, according to a letter he wrote to schools employees.

“I am making progress and getting stronger, but not fast enough for my own liking,” Dale wrote. “I am sorry and saddened to report that my doctors have not cleared me to return to work.”

Dale suffered an aortic aneurysm in early May and underwent surgery at Inova Fairfax hospital to address the ailment, which is a weakening of the wall of the aorta, the main artery that carries blood from the heart to the rest of the body.

The surgery was successful, and Dale has been recuperating at home for the past three weeks. School officials had said previously that Dale had intended to return on a part-time basis before the end of his nine-year tenure as superintendent. In the letter to employees, Dale wrote that he would not be able to resume his duties.

“I know I leave our system and students in excellent hands with teachers, support staff, and administrators who are some of the best educators in the nation,” Dale wrote. “I urge you to continue forward with your passion and dedication in all that we provide for our students and families.”

Veteran Texas educator Karen Garza will succeed Dale on July 1. School officials said she will likely begin transitioning to the top job next week. Dale told the staff he would remain in the area to consult with the school system and help Garza acclimate to Fairfax County.

“It has been my honor and privilege to be the Superintendent in Fairfax,” Dale wrote. “I will miss all of you very much.”