Ms Fischer said seasonal or weather-dependent jobs also contributed to families being short of cash this time of year.
"Outdoor workers are more likely to get rained off at this time of year and those working casual hospitality jobs may not get called in while there isn't anybody staying in town.
"Also if single parents have to take time off to care for their children when they are sick, that's going to impact how much money comes in each week."
Ms Fischer said the steep rise in demand for assistance could come down to a number of reasons.
"There have been changes to Work and Income and the Ministry of Social Development which has made the rules around the benefit much stricter.
"We have had more people coming in needing food because they have not met their benefit obligations and have been cut off.
"As well as this, the cost of living goes up every year but the change of income does not, so that could also be a contributor to the rise in demand."
Ms Fischer said the Salvation Army tried to "get through" each year, helping as many people as they could.
"We try support what Work and Income are doing so if they cut a person's benefit for whatever reason we back that up but we do give out food parcels to tide those people over for a week."