Thousands of blood donations were missed last week because of the heavy snow and freezing conditions that gripped the region.
Many people were simply unable to make it to donation centres and many mobile sessions around the region also had to be cancelled.
The NHS is now urging more people to donate after they have been left with very low stock levels.
The health service has a dedicated website which explains in detail who can and can't donate, and where the nearest donation sessions are to you.
It's not just whole blood they're short of, stocks of platelets are very low too - they're a component of blood that helps it clot and are often needed by cancer patients and those who've had major surgery.
Read more: A guide to becoming an organ donor