How the winter chill was cold enough this year to get this tree flowering

There is an Eastern dogwood tree (Cornus florida) — so-called since it is native to the Eastern US — at the end of my block, which I check on each spring to see if it’s flowering. I can happily report that it’s currently in bloom. It does not bloom every spring since it requires 400 hours of winter chill (temperatures below 45 degrees) to properly break dormancy with a flowery show . This winter, the North Hollywood weather station — which is closer to my residence