OMAHA, Neb. (AP) _ It's spring tornado season, and there's a ''radar war'' on among TV weather forecasters in this state that saw 52 twisters last year.

''We're the only TV market in the country where three major stations all have Doppler radar,'' said Tom Bevacqua of KMTV in Omaha. ''It's extremely competitive.''

Unlike conventional radar, Doppler can detect the speed and direction of winds in a storm, making a tornado easier to predict. Bevacqua's Channel 3 unveiled Doppler in February of last year, and local stations KETV and WOWT quickly followed suit.

Weatherman Jim Flowers at KETV has a staff of three meteorologists in addition to the sophisticated equipment, and he says his ratings get better when the weather gets worse.

''If we have bad weather in May and December, I think if you go back for those months you'll find our ratings may be slightly higher during those periods,'' Flowers said.

His competitors don't agree that KETV provides superior coverage of tornadoes, but they agree that all three stations invest a lot of time and money to report on stormy spring weather.

''When we found out (Channel) 3 was purchasing Doppler, we felt it incumbent on us to purchase Doppler radar in 1985,'' Flowers said.

KETV was runnerup in the race to acquire Doppler but did well in the battle for publicity. Flowers' station announced its new radar system on its 10 p.m. newscast the day before KMTV held a news conference to announce it was getting Doppler.

Publicity about the ''radar war,'' as it was billed, prompted a local radio station to poke fun by introducing a daily Doppler traffic report.

Dale Munson, weatherman at WOWT, acknowledged the heavy promotion of Doppler may have been counterproductive.

''Apparently the stations think it has quite a promotional impact, but I don't know,'' Munson said. ''You can oversell your product or service. People can say, 'They have Doppler. Now they'll tell us about every tornado that ever happens.'''

The radar war was expensive. Doppler can cost more than $100,000, depending on how much equipment a station already has.

''In the last 30 years there have been roughly 1,000 tornadoes within a 125-mile radius of Omaha,'' Flowers said. ''To me, that more than justifies the cost of the system.''

Munson, a TV weatherman for 23 years, said radar is one reason for an improvement in tornado coverage on television. Other reasons are watches and warnings issued by the National Weather Service and a sophisticated network of volunteer spotters, Munson said.

''There's been a terrific change and improvement,'' he said. ''Twenty years ago it was, 'Gee, there's a bad storm over there. I wonder what's going on.' And it was a tornado.''

All three Omaha stations interrupt programming immediately to broadcast a tornado warning, which means a tornado has been sighted.

''We'll even interrupt a commercial,'' Munson said. ''Heavens, can you imagine that - interrupting a commercial?''

Bevacqua said he's twice remained at the studio for 24 hours during periods of bad weather. Munson said he once was on the air continuously for 45 minutes.

''We had to interrupt the NBA playoffs, and boy, did we get some nasty phone calls about that,'' he said.

Weather service and civil defense officials said the ability of Omaha's TV stations to alert the public of possible twisters is one reason that no one in Omaha has been killed by a tornado in more than a decade.

The last tornado-related deaths here occurred in May 1975. Three people were killed when a twister ripped through the middle of the city. Property damage totaled $120 million, including 572 homes and 55 commercial or industrial buildings that were destroyed.

''The news media covers these events superbly,'' said Robert O'Brien of Douglas County Civil Defense.

But Bevacqua said he doubts that the quality of tornado coverage affects a station's ratings.

''If you're a 'Young And The Restless' watcher and a tornado watch is on, you're still going to watch 'The Young And The Restless,''' he said. ''I can't see people switching channels for that reason alone.''