Tuesday night, Twin Cities TV screens carried a National Weather Service warning of severe thunderstorms and hail in Hennepin and Wright counties.

Yet, tranquil skies reigned overhead. Viewers may have wondered, but at KSTP, Channel 5, Dave Dahl "had steam coming out my ears."

He was still irked the next day. "In my 30-year career, it was the worst case of over-warning I have seen," the normally affable chief meteorologist said Wednesday.

The government's top local weatherman agrees, calling the warnings "questionable."

In fact, the agency may revise its standards because increasingly sensitive weather-tracking equipment is bringing more frequent weather warnings.

Weather experts fear that too many false alarms may lead people to not take precautions in the event that a truly serious storm is threatening the area.

Tuesday's alert was triggered by reports of an isolated storm cell that briefly produced dime-size hail and windy conditions Tuesday evening near the town of Dassel, in Wright County.

That automatically brought a warning from the National Weather Service, which defines "severe weather" as gusts up to 40 miles an hour accompanied by ¾-inch hail.

Television stations are required by the Federal Communications Commission to provide weather warnings to viewers, said Chris Berg, KSTP's news director.

"The rule says that if life and property are being threatened by weather, we must broadcast that information," Berg said. "How we do it is left up to the interpretation of each broadcaster based on the severity of the threat."

In general, broadcasters respond to severe weather by putting Weather Service "crawls" across their programming. Milder storms result in a lower-key warning. More severe weather -- the kind that rips off roofs and dents cars -- will cause stations to interrupt programming altogether.

Meteorologists walk a fine line, said Paul Douglas, chief meteorologist for WCCO, Channel 4.

"Nobody wants to be caught with their Doppler down," Douglas said. "The thing meteorologists abhor is a tornado survivor blurting out that there was no warning."

On Tuesday night, however, Dahl's own equipment showed the limited scope of the storm. So he yanked the Wright County warning before the station's 10 p.m. newscast began. And while a Hennepin County storm message continued to show on the screen, he downplayed its severity to viewers.

The Weather Service "warned huge counties about two small storms," Dahl said Wednesday.

Evaluating hail

Craig Edwards, meteorologist in chief of the National Weather Service bureau in Chanhassen, said he planned "to talk to the meteorologists who were on duty about that."

In general, Edwards said, "The statistics show that we have sufficient cause to reevaluate our warning criteria."