The brutal winter in much of the East and Midwest could be taking its toll on St. Patrick's Day revelry.

Fewer consumers are expected to celebrate the green holiday that ushers in the arrival of spring, according to new research commissioned by the National Retail Federation. But, those who do are expected to spend more.

Nearly 127 million Americans are planning to celebrate the traditional Irish holiday in 2015, down 4.7 percent from the expected 133 million revelers last year.

At the same time, total spending on the holiday is predicted to be slightly lower at $4.2 billion, compared with $4.6 billion last year. The survey, commissioned by the NRF and conducted by consultancy Proper Insight and Analytics, polled 6,186 consumers in February.

Despite a blooming economy, the winter doldrums could be keeping consumers down, according to NRF officials.

"Clearly we see that … consumers are much more at ease with their spending," said Kathy Grannis, NRF spokeswoman. "This is just one of those holidays you don't have to celebrate, you could just go home, but for those who may have partied too hard last year, maybe they are just taking a small step back this year and reviewing their budgets," she said.

Those who do plan on celebrating St. Patrick's Day this year are expected to spend, on average, slightly more than they did last year. The NRF is predicting consumers will spend $39.70 on average, 75 cents more than last year.

Most of the celebrating will be by adults ages 25 to 34 since two in five are planning to a head to a bar or restaurant to mark the holiday. They'll also spend the most, an average of $41.69. Millennials, ages 18 to 24 will spend a bit less, an average of $38.55.

The bulk of those who mark the holiday will do so by wearing green, with 82 percent of adults ages 18 and over planning to dress up for St. Patrick's Day.