As the remnants of Hurricane Florence moved through the region, the University of Maryland Police Department yesterday alerted the campus community of a threatening tornado and ordered people to immediately seek shelter, lifting the warning a half-hour later when no twister was spotted in the area.

The UMPD later defended its decision to issue the tornado warning without a government-issued one, saying the department was acting on information provided by private weather forecaster AccuWeather specifically for the campus.

The 5:35 p.m. warning via the UMD Alert system, accompanied by emergency sirens, advised everyone on campus to stay indoors, avoid windows and go to the lowest level of the building. UMD Alerts, operated by the police department, announced just after 6 p.m. that the warning had been lifted because the storm rotation had shifted to the north.

The National Weather Service had issued a tornado watch announced on Twitter at 3:40 p.m. Monday for parts of the District of Columbia, Maryland and Virginia, indicating that tornadoes are possible; Warnings were issued for parts of northern Virginia and southern Maryland,, meaning that one has been sighted or indicated on radar. The watch was lifted soon after 8 p.m. A tornado that touched down in Richmond, Va., earlier caused one fatality, local authorities said.

The university contracts with AccuWeather, which notified it that a tornado may be imminent in the area, a police spokeswoman said in a written statement last night.

“The safety of our campus community is our foremost priority,” Sgt. Rosanne Hoaas said in the statement. “In the interest of public safety, the University of Maryland Police Department contracts with AccuWeather to receive real-time information on storm paths approaching the footprint of our campus community.”

Jonathan Porter, vice president of AccuWeather Enterprise Solutions, told Maryland Today that Florence-related storms already had caused tornadoes to spin up quickly to the south. "Our meteorologists noted strong rotation in a particular cell that had popped up near campus, and we felt the strong rotation could produce a tornado imminently," he said.

UMD’s use of AccuWeather brought criticism on Twitter from Baltimore-Washington meteorologists, including The Washington Post’s Capital Weather Gang: “It creates substantial public confusion when you declare a warning that differs from the official government source. Furthermore, the rotation in the storm was not near your location and the government was right. Your source was not.”

A tornado warning from AccuWeather in 2011 brought a similar response from university police, along with local news coverage of the false alarm. Further back, two students were killed on campus in 2001 when a tornado tossed their car into the air; the storm did substantial damage to the university as well.

On campus, Shuttle-UM service was briefly suspended and meetings were canceled amid the emergency alert.

Police said on a campus of more than 50,000, that it’s important to issue alerts specific to our community “to ensure that safety messages are quickly and accurately conveyed to our campus community,” the UMPD said. “As soon as we were alerted that the storm path shifted, we issued an ‘all clear’ message to our community.”