“It hit me when we got off the bus and walked up and saw the Crossroads building,” Ms. Lennon said. “We had all our stuff. We were tired. We’d already had enough, and it was just starting.”

The number of families who have sought help this year at Crossroads has already surpassed the total for all of 2009. Through July, 324 families had come needing shelter, compared with 278 all of last year.

National data on current shelter populations are not yet available, but checks with other major family shelters across the country found similar increases.

The Y.W.C.A. Family Center in Columbus, Ohio, one of the largest family shelters in the state, has seen an occupancy increase of more than 20 percent over the last three months compared with the same period last year. The UMOM New Day Center in Phoenix, the largest family shelter in Arizona, has had a more than 30 percent increase in families calling for shelter over the last few months.

Without national data, it is impossible to say for certain whether these are anomalies. Clearly, however, many families are still being sucked into the swirling financial drain that leads to homelessness.

The Griffith family moved from Rhode Island to Florida two years ago after Mr. Griffith, who was working as a waiter at an Applebee’s restaurant, asked to be transferred to one opening in Spring Hill, an hour north of Tampa, where he figured the cost of living would be lower.