Here's how the 12z GFS verifies against 00z RAOB observations.

Biggest thing that pops out at me is stronger than modeled ridging especially downstream of our shortwave but also upstream over the SW.

Both argue in favor of the trend towards amplification we've seen today. pic.twitter.com/Nh8pkFRM27

— Jack Sillin πŸ‡ΊπŸ‡¦ (@JackSillin) January 31, 2021