As most area families prepare to fill up on turkey, cranberry sauce and other Thanksgiving Day delicacies, some local churches are concerned that they may not be able to provide free holiday meals tomorrow for the growing number of poor persons who need them.

"We have enough to feed 700 to 800 this year," said the Rev. Jack Woodard of St. Stephen & the Incarnation Episcopal Church at 16th and Newton streets NW. "But if attendance doubles, as it has with our other meal programs, we're sunk."

This year at least 100 needy families, 30 more than last year, asked All Souls Unitarian Church at 16th and Harvard streets for Thanksgiving groceries, which the church distributes annually, as well as on a monthly emergency basis. All Souls' assistant pastor, the Rev. Frank Robertson, said he has called several Unitarian ministers personally to ask them to make pleas from the pulpit for increased charity this year. Still, Robertson says, only the first 60 families that apply can be sure of getting free food at his church this year.

Church after church reported similiar difficulties with their food programs, as have other private community assistance groups. Until recent months, SOME Inc. (So Others Might Eat), a local nonprofit organization that operates a soup kitchen at 71 O St. NW, fed an average of about 250 people a day, according to its director, the Rev. John Adams. By last week that figure had reached an all-time high of 600.

Throughout the city, churches and social service groups are finding that the needy are turning up at their doors or in their soup lines earlier and earlier each month as Social Security, welfare and food stamp allotments are stretched ever thinner by continuing inflation.

"Churches are overwhelmed now," says Woodard. "I'm not sure if we can take on that burden." He says he senses a change of mood among the poor and is concerned about what it might portend. "After watching people get hungrier month by month," he says, "one wonders how long people will stand for this, and what kind of reaction on the part of the hungry will be necessary to make our political leadership realize there's a crisis affecting poor people."

For many years, St. Stephen's, like many other churches, has tried to keep a supply of food on hand to help the needy in emergencies. Woodard says he can't remember having run out food in years past. Now, he says, the cupboard, replenished by parishioners every Sunday, is bare by Tuesday.

At All Souls', according to Robertson, the church's monthly cash allotments have been drying up before the third week of the month.

Many area religious groups collected foodstuffs and special offerings at services this weekend and have been distributing them to the needy, and a growing number say that this year there seem to be too few loaves and fishes to satisfy the multitude that needs them.

At least one local church group, however, reports a cornucopia that still runneth over, and expects no problems feeding anyone who comes to its annual Thanksgiving Day dinner for the poor. The dinner, sponsored by the Downtown Cluster of Congregations at Calvary Baptist Church, attracted more than 600 people last year, and "As far as we're concerned, it's still come one, come all and bring your buddies," says the Rev. George Hill, pastor of the church at 755 8th St. NW.