PHOENIX - With donations dropping off during the holiday season, Arizona is facing a blood supply shortage while demand rises.

Sue Thew, spokeswoman for Vitalant in Arizona, said the 10 slowest days of the year for blood donation are Christmas Day through New Year's Day, creating a "blood shortage emergency."

"It’s so critical that people donate blood right now, because while we’ve just come off of the most difficult time of the year to attract blood donors, more blood transfusions are required in January than during any other month of the year because patients postpone essential surgeries until right after the holidays," she told KTAR News 92.3 FM on Wednesday.

Thew said all blood types are needed, but supplies for universal types are especially low.

"We have less than a two-day blood supply for Type O blood, which is one of the universal blood types, and less than a one-day blood supply for Type O-negative, the universal blood type used in emergencies and traumas," she said.

To address the urgent need, Vitalant, the nation's largest independent, nonprofit blood services provider, is holding the Saving Arizona Blood Drive on Sunday.

The event is scheduled for 7 a.m. to 1 p.m. at the Tempe Center for the Arts (700 W. Rio Salado Parkway). Appointments, which can be made online or by calling 877-25-VITAL (877-258-4825), are encouraged.

Participants will receive as well as give. Vitalant is offering each doner a voucher for a pizza from Streets of New York, one-day admission courtesy of The Thunderbirds to next month's Waste Management Phoenix Open golf tournament, and a voucher redeemable by mail for a long-sleeved T-shirt.

In addition, all donors until Jan. 20 will be entered into a drawing for Vitalant's Big Trip to the Big Game Giveaway. The prize includes tickets to the Super Bowl in Glendale and four nights at a Scottsdale resort as part of a package worth more than $27,000.

"We’re trying to reach the need of 600 blood donors every single day for patients in 62 different hospitals across our state," Thew said. "It’s very crucial that people donate blood right now because we desperately need to replenish our supplies so that patient care is not compromised."

KTAR News 92.3 FM’s Heidi Hommel contributed to this report.