Washington (CNN) -- The director of the National Weather Service announced his sudden retirement last week after an internal investigation found the agency shifted some of its funding internally without asking Congress, according to officials familiar with the situation.

Jack Hayes, a veteran meteorologist who headed the weather service since 2007, announced his retirement Friday and will be succeeded by an acting assistant administrator Tuesday, said a statement by Jane Lubchenco, the undersecretary of commerce for oceans and atmosphere.

Lubchenco's statement Friday made no mention of the investigation that found more than $30 million had been used by the National Weather Service to pay for costs that differed from the intended budgeted funding.

All the officials involved emphasized that there was no evidence that any of the money was for personal gain.

"National Weather Service employees engaged in the reprogramming of funds without congressional notification as required," said a statement Monday by Scott Smullen, a spokesman for the National Oceanic and Atmospheric Administration, which includes the weather service.

"The investigation also found that no funds were used on inappropriate items, they were simply used in different categories than originally budgeted," Smullen's statement said. The investigation found no evidence of corruption or personal financial gain in these actions. "We do not believe any money was moved out of the National Weather Service."