The good news for Fairfax County students and teachers is that school will be closed Tuesday as weather forecasters call for a thick blanket of snow to cover the Washington region.

The bad news is that Tuesday will be the fourth day that the Fairfax County public schools administration has canceled classes and that the day of learning lost to sledding and hot cocoa will be made up on Monday, Feb. 17, the Presidents’ Day holiday.

Jeff Platenberg, the Fairfax County schools assistant superintendent for facilities and transportation, said he had been following forecasts closely Monday. In the late evening, Platenberg participated in a conference call with representatives from the National Weather Service and the Virginia Department of Transportation.

Platenberg said he decided to close Fairfax schools Tuesday based on Weather Service forecasters’ high degree of confidence that the snow would fall at a rate of one to two inches per hour throughout the morning and evening commutes.

“No matter what, we’d have been putting students in harm’s way,” Platenberg said. “That’s not a risk I’m willing to take.”

Each year the school system includes three extra days on the academic calendar in the event of closings due to inclement weather. Earlier this month, amid single-digit temperatures, the administration took caution and canceled classes a third time this school year. By Virginia law, students in public schools must attend classes for 180 days of the year. The makeup day scheduled for Feb. 17 will ensure that Fairfax schools remain within the letter of the law.

Platenberg said that the forecasters called for possibly eight inches of snow in areas around Washington, with wind gusts up to 30 mph. About 4,000 trucks from VDOT will be plowing and treating the roads in the early hours Tuesday, Platenberg said he was told during the conference call.

All of that information led Platenberg to make the closing decision before 10 p.m. Monday, despite temperatures hovering in the 40s earlier in the evening.

“When you look at the amount of volume we have in this area and the terrain, it’s in the best interest of students to keep them off the roads,” Platenberg said.

He acknowledged that it can be a hassle for some parents to take leave from work to stay home or make last-minute plans for a babysitter when school is canceled. But student safety is his first concern, he said.

“An inconvenience is strictly that — it’s an inconvenience,” Platenberg said. “Every decision, I’m thinking: What’s in the best interest of our students?”