Canadian Blood Services hopes you’ll roll up your sleeve and donate before Canada Day.

The organization is looking for at least 515 blood donors in Winnipeg by July 2to meet the needs of hospital patients over the summer.

It says the need for blood goes up in July and August—the same time when donations typically dip.

“The weather's nice, so people are outdoors at the cabin or at the lake doing other activities--but donation isn't always top of mind,” said Mike Choi, CBS territory manager.

All blood types are needed, but Type O is especially needed, said Choi.

You can make an appointment to donate by visiting blood.ca or calling 1-888-236-6283