MILWAUKEE (CBS 58) -- The Milwaukee County Zoo's 21st annual blood drive opened Wednesday, June 17 with dozens turning out despite rainy weather. The drive runs through Friday, June 19 from 10 a.m. to 4 p.m.

The Red Cross says blood is being sent to hospitals faster than donations are coming in, a situation it describes as an urgent need. "That update just came out today, so we really, really need blood," said Lizzie Paynt, account manager with the Red Cross.

Summer typically sees a significant drop in donations, according to the Red Cross, making community drives important for maintaining hospital blood supply.

Anyone who donates will receive free same-day zoo admission, parking and two Summerfest tickets.

Click here for more details.