Of all the Seasonal Inspirations destined to inundate TV schedules in coming weeks, few are likely to match the unaffected warmth and glow of "A Christmas Without Snow," on CBS tonight, and "Stepping Out -- The DeBolts Grow Up," on HBO tonight.

Both films were made under the aegis of John Korty, the filmmaker who could have rested on the laurel of "The Autobiography of Miss Jane Pittman" for about 100 years if he'd felt like it. Korty co-wrote, co-produced and directed "Christmas" and was executive producer of "Stepping Out."

As a filmmaker Korty specializes in finding but never falsifying a strain of basic good will in people. His films are about everyday valor and decency, about the surmountability of odds. Korty celebrates ordinariness but he knows how to locate the extraordinary within it. He understands exactly what kind of material works on television and how to measure out effects in intimate quarters.

"A Christmas Without Snow," at 9 on Channel 9, is so deft and subtle that you hardly realize you're being grabbed emotionally until it's entirely too late to pull away. Michael Learned plays a divorcee from Omaha who moves to San Francisco and joins the local church choir, just at that moment undergoing a strict reconstruction at the hands of a stern new choirmaster played by John Houseman.

The film is like the choir -- an ensemble effort with several standout solos. The choir members are rehearsing their holiday blockbuster, Handel's "Messiah," and trying to maintain lives on the side. Learned tells kindly lies to Mom on the phone and uses "This is only temporary" as a typing exercise when she can't get a job teaching and becomes a secretary. And she gently fends off the understanding advances of a fellow choir member played by Ramon Bieri.

Other members of the choir include a likable gray-haired codger (William Swetland) who says "I belong to The Church of Beautiful Women," a 72-year-old woman (Ruth Nelson) whose greatest fear right now is of being dropped from the group ("Giving up all this would be like dying") and the slightly mysterious Mrs. Kim (Daisietta Kim) whose polished soprano knocks everyone for a loop when she sings "I Know That My Redeemer Liveth" during auditions.

Valerie Curtin plays a frustrated and meddlesome klutz given to doing precisely the wrong thing. A commanding young black actor, Calvin Levels, plays a member of the choir wrongly accused of vandalism, and veteran Beah Richards is the grandmother who works nights cleaning offices so he can go to college.

The story, which is really a series of interlocking vignettes leading up to the Hallelujah Chorus, has elements that in other hands might lead to the sudsiest sort of ersatz uplift. But Korty sustains an attitude that is immaculately gushless and precise."A Christmas Without Snow" is so sly about its sentiment that one never feels prodded or poked; it's just about perfect. 'Stepping Out'

"Stepping Out -- The DeBolts Grow Up" is an authentic and heartening uplifter that updates and amplifies Korty's 1978 documentary "Who Are the DeBolts? And Where Did They Get 19 Kids?" That film, shown on ABC last year, introduced the nation to Bob and Dorothy Debolt, who've adopted by latest count 20 kids -- most of them physically handicapped -- over the past 25 years, and have temporarily cared for many others.

The sequel with be shown several times this month, starting tonight, on Time-Life's Home Box Office, the pay-TV network. HBO is available in this area to subscribers of Arlington's Metrocable system and Marquee Television, which picks up the signal by satellite and beams it to apartment buildings and private homes.

On Christmas Day, 1979, director and cinematographer Jon Else moved in on the DeBolts to begin shooting "Stepping Out" at their home. The family grew to 20 kids during filming, when the DeBolts officially adopted Renaldo, a 15-year-old who limps from the polio he had as a child. But the star of the movie is J.R., 16, who is blind and paralyzed from the waist down.

Adopted by the DeBolts six years ago, J.R. used to attend a special school for the blind, but was determined to go to a regular junior high with "normal" kids. In the film, he is seen visiting the school to learn how to inch his way around. He practices writing his signature. He climbs aboard the school bus. When he bumps into a classmate, he says "Oops, sorry" and matter-of-factly gets back on course.

He is more incredible than anything on "That's Incredible" and more real than anyone on "Real People," but Else doesn't ask for pity any more than J.R. does. What one feels is admiration -- and a little guilt for ever having complained about an inconvenience of any kind.

At the DeBolt house, typical domestic questions like "Have you finished your homework?" are mingled with more unusual ones like "Who lost the screws out of their braces today?" One might see a pair of sneakers sitting by a bed here, but they have artificial legs attached; their owner, legless, is sitting on the floor and playing. And a young girl in the family finds that having no hands does not prevent her from playing the xylophone in the school band.

After "Who Are the DeBolts?" was shown on TV, Dorothy DeBolt said yesterday from her home, "the impact was absolutely enormous. We recieved -- oh, gosh -- 50,000 letters, and a good third of those were from people who were interested in adopting children with special needs." The DeBolts set up a foundation, Aid to the Adoption of Special Kids (AASK) to encourage that.

"The new film proves that the children did not remain in our seemingly protective society, under one roof," DeBolt said. "They're out there doing things, like other kids. I think that's a valuable point to make." Only eight of the DeBolt kids now live at home; the others have married or gone out on their own.

The DeBolts were paid "a very, very small amount" by the filmmakers for the first movie, DeBolt said, and have "a percentage" of revenue from the sequel "to help us support our brood." She and her husband have made more than 200 public speaking engagements in the past two years, and their speaker's fee shot up after the first film was shown on ABC, which has first refusal rights on the second after it plays HBO.

TV networks were afraid of the first film; perhaps they thought audiences would be unable to watch the children struggle, and fall down, and get up again, or put on their arms or legs. But then Henry Winkler of "Happy Days" took the film under his wing and, with himself added as narrator and host, got ABC to buy it.

"It's a sad commentary on the mentality of the networks," DeBolt says, but she praises Winkler for his "sensitivity" and says he is still a friend of the family.

When "Stepping Out" premieres on HBO tonight, the DeBolts will have to hie off to a motel to watch it. They don't get HBO at home. In fact, they don't have a television set. "We took it out about five years ago," DeBolt says. "We found it destroys a lot of communication, and with so many kids, it became impossible to police it. We borrow one every so often and watch ourselves on it, and take an ego trip."

There are times, though, when mean old TV seems pretty close to indispensable.With films like "A Christmas Without Snow" and "Stepping Out," it becomes virtually wonderful. And heaven and nature sing.