The Oregon & Southwest Washington Blood Program is asking donors to give more blood after collections dipped sharply because of the heat wave.
The group said they had to cancel or suspend several blood drives at mobile locations that don't have air-conditioning.
Dr. James P. AuBuchon, the program's president, says he's worried about a possible shortage with more hot days in the forecast.
AuBuchon says the group suspends blood drives when temperatures go above 80 degrees, because they want to make sure donors are comfortable. He estimates they missed 200 collections last week because of the heat.