TORONTO -- Canada has administered more than 974,600 first doses of the COVID-19 vaccine, and more than 294,700 second doses. Here’s what else you need to know to start your day.

1. Border rules: There could be lineups at Canada's 117 border crossings with the U.S. Monday, as non-essential travellers now have to provide proof of a COVID-19 test.

2. Vaccine capacity: Amid claims the federal government has blocked provinces from buying their own COVID-19 vaccine supplies, Ottawa says it will soon reach out to strategize how to work together to boost Canada’s domestic manufacturing capacity.  

3. Air quality: The levels of various greenhouse gases in the air in several major Canadian cities fell sharply around the start of the COVID-19 pandemic, according to a new study.  

4. SolarWinds hack: A hacking campaign that used a U.S. tech company as a springboard to compromise a raft of U.S. government agencies is "the largest and most sophisticated attack the world has ever seen," Microsoft Corp President Brad Smith said.  

5. Big brother Archie: The Duke and Duchess of Sussex are expecting a second child, a spokesperson for the couple tells CTV News.  

One more thing…

Polar vortex: We have good news for the many parts of Canada that are still struggling through unusually and even historically cold temperatures: the end is in sight.

Cold weather