About 50 schools in Baltimore that lack air conditioning dismissed students early on Monday, the first day of fall, for the third time this month as temperatures hit a stifling 90 degrees.

Due to the high temperatures, about 50 schools without air conditioning were to dismiss three hours early, Baltimore City Public Schools said in a statement on Monday morning.

The school district previously announced the affected schools would dismiss three hours early on Sept. 12 and two hours early on Sept. 4, the second day of classes.

The schools are listed on the district’ website as designated for early dismissal on “extremely hot days.” Temperatures have repeatedly reached the low 90s in Baltimore this month.

Maryland Gov. Larry Hogan wrote in a post on Facebook Monday afternoon that this was "the third time in the new school year that students are being deprived of valuable time in the classroom because of this problem."

"I am appalled that this continues to detract from the education of thousands of young Marylanders who deserve a safe, healthy, and comfortable learning environment," he wrote. "This is the third-highest funded large school system in America — where’s the accountability?"

Earlier Monday, in response to the third day of early dismissals, Maryland Gov. Larry Hogan’s office referred to a previous statement the governor made after the first day of early dismissals this year.

“It is outrageous and completely unacceptable that the third-highest funded school system in America still refuses to put air conditioning in all their schools, and had to send kids home from 57 hot school buildings,” Hogan wrote in a statement on Sept. 4. “The Baltimore City School System must be held accountable.”

According to the Baltimore Sun, the city has some of Maryland’s oldest school buildings and a maintenance backlog of roughly $3 billion worth of projects. In an update to its air-conditioning plan published in May, the district said its buildings overall were the oldest of any school district in the state and "numerous buildings need significant system upgrades or complete replacement."

In 2016, Hogan threatened to withhold millions of dollars in school construction funding, calling on officials to come up with a plan to install air conditioning in the schools.

The school district said in its May plan that it developed a plan in 2017 to ensure all buildings in its district would have air-conditioning by the 2022-2023 school year, but it added that completion by that time was no longer possible given available funding.

In a previous statement, the Baltimore Teachers Union said the early dismissals did not come as a surprise.

“Our scholars continue to suffer academically because their instructional time is interrupted due to these extreme conditions,” Diamonté Brown, president of the union, said. “While the district works to find and implement a resolution for this ongoing problem, we, as a community, must continue to develop creative and innovative solutions ... to help our educators provide our scholars with a classroom environment that is conducive for learning.”

The union collected hundreds of fans for teachers to use in overheated classrooms.

The union and Baltimore City Public Schools did not respond to immediate request for comment Monday.