A unusually strong storm offshore the Pacific Northwest is strengthening on approach to the area, which will lead to very heavy rains in California. This thread aims to place the storm's strength into context. Image: 0000 UTC October 24 surface analysis from OPC/WPC. (1 of x) @NWSOPC forecasts the storm to strengthen to a central pressure of 942 hPa/27.82" by Sun AM. Since this system isn't tropical, its wind field is broader/less intense than a hurricane with this central pressure, but hurricane-force winds exist in its immediate vicinity offshore.

As has been recently noted on Twitter, what was then HPC came up with a regional name map for the United States about 20 years ago. It was simple, and meant to acquaint new forecasters to the lower 48. @TornadoQuest @AndrewWxCenter (1 of x). @TornadoQuest @AndrewWxCenter After its creation, a more detailed map seemed necessary as local forecast offices referred to areas that were smaller in scale which we were unfamiliar. Three years ago, WPC worked on a new regional map for the United States, using input from other NWS offices. (2 of x)