New York It has an appropriately autumnal feel to it. But Jeff Sweet's ''Porch,'' which opened the Lamb's Theatre Company season in its Little Theatre, is more than a wistful reminiscence about life in small-town America. It is a well-crafted, well-acted, professional piece of Off Broadway theater. Despite the evening's modest proportions - the play is essentially an extended one-act with an added prologue - ''Porch'' contains the dramatic seeds of the larger themes found in such full-fledged works as Thorton Wilder's ''Our Town.'' Although it is a relatively unremarkable domestic tale - a grown daughter living in New York City returns home to her ailing father and former boyfriend in small-town Ohio - ''Porch'' is rich in its portrayal of human feeling. This is largely due to Sweet's ability to capture in dialogue and dramatic progression the emotional ups and downs that ripple through everyday conversation. Although the father and daughter bicker over things common to many families - sibling rivalry and lack of grandchildren - and the former boyfriend is as gawky and well-meaning as any, the playwright rescues his characters from triteness. Sweet is careful never to rush his material or overload the characters' speech with clunky, obvious plot details. Past incidents are mentioned first in passing and fully revealed only in the second or third reference. As a result, Sweet's dialogue sits well on the ear, and the characters, despite their commonplace nature, are never cliched. Praise is also due the excellent production, which, under Nan Harris's able direction, never oversteps the bounds of the script. Jill Eikenberry as the daughter, Amy; Clarke Gordon as the father; and Gary Bayer as boyfriend Tom give strong, highly nuanced performances that pick up Sweet's subtle emotional signals and telegraph them to the audience. When Tom, with his sport shirt sleeves buttoned all the way down and the pens lined up in the breast pocket, steps off the porch without a goodnight kiss, we are pained by a tangible loss. Although the production is a revival of a play that originally opened in the mid-'70s, ''Porch'' has sufficient staying power. Only the argument about Miss, Mrs., or Ms. might strike some as a mite stale around the edges. A prologue that's been added, which brings a fourth character into the quiet little fray, is thematically linked to the play, but not essential. The Michael Smith-designed set of flagstone path, chintz-covered porch rocker , and piles of windblown leaves visually underscores the bittersweet nature of the work. And the lighting, by Marc Malamud, etches an appropriately leafy pattern onto the side of the yellow clapboard house. One might only have wished for a gradual darkening of the lights, when Tom and Amy sit beside each other and try to reignite romantic sparks. — Drama by Jeff Sweet.