A lot of this comes down to the NAO. We’ve lost that stout blocking signature significantly. The early month period of cold was only going to be possible if the -NAO bullied the rest of the patten into submission.
Mid-month onward, this is the first time (and I hate to say it), that I’m really starting to see some red flags on the cold forecast. On modeling it’s essentially the traditional ensembles vs AI. The AI ensembles are much more aggressive in favor of a cold pattern getting established by mid month so we’ll get a very good verification check in a week or two. Onto my red flags: what exactly is moving this pattern? PNA looks neutral-ish, we’re losing the -NAO. -EPOs are great, that should dump some cold into the conus but without a solid western ridge in place, my bet would be that it dumps into the Rockies and bleeds east slowly. That would be a modified mess, even if it makes it here.
- MJO - stuck in the cod. This coupled with our meh teleconnections are combining for model volatility. We’re at a fork in the road and something has to give.
- ENSO still favors a SER and we need help elsewhere to beat that down.