A new zone map is out for the first time in over a 10 years
Zones are typically defined by a 10-degree Fahrenheit difference in the average annual minimum temperature and are particularly important to pay attention to when gardening in our area if you want success with both blooms and crops.
The United States Department of Agriculture has an excellent website page showing the updated Zones, and provides Map Downloads and also a primer on how to use the maps here.
While our specific zone (according to zip code) hasn't changed - we're still in Zone 5b, we have see a +2 degree F change in the past 10 years.
Map credit: USDA