GRAND FORKS (AP) - A change in the way the National Weather Service issues severe weather warnings really is no change at all for the weather service in North Dakota, a weather service data program manager says.

The system officially takes effect Oct. 1, switching from alerts based on county lines to notices aimed at specific communities, weather service officials said.

"It's the way we've been doing things for years, but they've just formally rolled it out," said Mark Ewens, a data program manager at the National Weather Service office in Grand Forks.

The new warning system improves the way data is displayed, he said.

"The Grand Forks office was one of the testbed offices years ago, so we've been doing it for quite a while," Ewens said.

The software allows warnings to show the directions in which a storm moves, for example, he said. The new alerts, known as storm-based warnings, could reduce a warning area from thousands of square miles to a few hundred square miles, experts have said.

On a radar map, the warned areas appear as highlighted polygons rather than entire counties.

"Eventually, all hazards will be able to be defined that way instead, as more people go to graphic design instead of a textual design," Ewens said.

"Its big advantage is that it gives the person using the warnings a better idea of where the severe threat is going to be," said Jim Fors, a National Weather Service meteorologist in Bismarck, which also has used the system for the past few years.

It's "visually nice," Fors said.

Cell phone users may find it easier to get weather warnings using the new system.

"We've already incorporated latitudes and longitudes in the warning. It opens up lots of possibilities with that," Fors said.

"Really, the bottom-line intent is to refine the threat area so people are able to make their own decisions," Ewens said.

Forecasting has improved, especially in short-term watches and warnings and long-term outlooks, he said. Still, there could be surprises.

"There are so many variable in the atmosphere," Ewens said.