6z GFS and 12z Euro show that we still have a possible storm window in the Dec 9-10 window and probably more chances beyond that. But from a RELOAD/pattern point of view, it's become clear that things will take more time and/or be more variable. Two reasons for that that I see. Kudos to Prince GEFS here for sniffing this out sooner than King EPS.
1. Our ridge bridge is not going to capture a piece of the tropospheric PV underneath it like we thought it would. Look here, we're going to get our ridge bridge with the PV underneath!
But, it doesn't last. The AK ridging wobbles back west, opening a big fat exit door and the PV escapes.
This is what also helps let the SE ridge flex. No PV to squash it down. It also means we're stuck with somewhat mediocre air masses vs some good arctic air. Contrast that to what we thought we'd have as of last weekend. We thought/hoped the ridge bridge would persist, and keep the PV trapped. But it doesn't look like it.
2. The damn -PNA. It's a Nina, so can't be surprised, but it just doesn't want to quit. If we had that PV underneath our -NAO (which does seem wonderfully strong and persistent across all guidance), we could manage the fairly modest -PNA that seems to never want to quit. But without that cold air mass nearby helping to change the waveguide and force a trough over us, even the somewhat mediocre -PNA shown on today's 12z GEFS would give us fits.
Not sure how this all plays out besides continuing to counsel patience. The very good news is that we seem to have a very durable -NAO/-AO combination building within the next 3-4 days. It's not fantasy land! The blocking is coming. Question is when we can take advantage. With that blocking around, Op guidance will produce weird solutions and combine that with the Nina and it's not a recipe for long-track storms regardless. With that blocking, if we can time up a shortwave with a fresh airmass, we can cash in quick.