CAPE

The stronger shortwave is the biggest difference yes. If it's that amped its going to be hard to get it to track underneath given the general h5 setup.

No Kyle Hamilton today Drinking early.

He is one of these Philly drive-by debs we used to see a lot of in the past.

In order for this window to work out for the lowlands, wave timing/spacing is especially critical, given there isn't a sustained block in place and cold air availability is marginal. Comparing this GFS run to the ones with the better outcomes, there is a bit too much spacing relative to the 50-50 vortex, and ofc the shortwave itself is stronger/ more amped. That might work if there was a block, but it becomes really touchy in this case wrt the 50-50 position/strength. Anyway, still plenty of time and a pretty good bet guidance doesn't have the details nailed down at this juncture.

Ha I was just about to do something like this illustrating the shifts we ideally want to occur. I can see it. Might be a bit of a fantasy now but hopefully it becomes real.

The advertised look up top towards mid month is getting close to 'that look'. The overall pattern still needs some work. The mid month period would favor NW tracks with that trough position. Get the MJO into the better phases with an extended NPJ and we should see a more Nino-like look on the Pacific side, with the Aleutian low in a better spot and a shift in the ridge position from offshore to the western US. That change, with a HL block in place, would set us up nicely for the latter part of Jan into Feb.

The officials completely effed up on the initial attempt. That conversion should have stood. That being said, after that debacle just kick the damn extra point and take it to OT.

I almost posted the GEPS h5 panel instead- at the end of the run it has the NPAC low digging southward closer to the more classic position over the Aleutians, with an amplifying EPO ridge. If this Nino is going to behave like a strong Nino that feature should become more prominent going forward.

The advertised 500mb pattern progression continues to look more favorable towards mid month. Hard to nitpick the HL look with a -AO/NAO, and the EPO trending negative. Key features end up in good locations- lower heights in the 50-50 region, an Aleutian low, and a TPV lobe over Hudson underneath the block.

Yeah the 6z GEFS is very similar to 0z wrt track, temps, precip. At this point places west of I-95 and esp further west look favored for a mostly or all snow event. Lotta runs to go. We got something legit to track finally.

Not sure about that. There are subtle differences. The 50-50 low is not as strong/consolidated, and a tad further north. The overall evolution and outcome meteorologically is the same, but obv some major differences wrt the outcome we are interested in. I have been planning to take a trip to Canaan sometime in Jan, so this might be the time.

A big difference at h5 can be seen comparing these 2 panels. Not as much NS energy involvement on the 6z run at this point.

it really is a disease.

Bit of a tradeoff. The stronger/closer 50-50 low is largely what's damping the wave/ keeping it more suppressed on the mean. Not really worth doing more analysis, as there are many more model cycles to go.

HH GEFS is further southeast with the low and a bit weaker. Decreased spacing wrt both the 50-50 low and the next wave out west are the most obvious reason on the mean. After thoroughly enjoying a 120, I'm not at all interested in poring over the members for further detail. The mean still implies frozen into the MA. On to the next run.

It phases with what's left of the 50-50 from the Jan 4th wave, which then reinforces the positive h5 heights over GL. That's the basic mechanism of an atmospheric block, and what keeps it sustained for a period of time.

Only subtle differences in the upper levels and the overall evolution for the Jan 7th event the last 2 GFS runs. Nice to see such consistency in back to back op runs at this stage.

Ends up mostly rain but another step in the right direction for that period, which looked like a pure cutter with mild rain a couple runs ago.

That's a legit block with surface HP wedging south.

This is probably somewhere between a squirrel and a moose.

This is pretty.

I get it. I am 'hunting' snow chances. Don't care if its a squirrel or a moose. All good.

lol we know dude.

I made a post focusing on number 2, which I believe to be the biggest difference on the 12z run compared to the previous few, where the resulting surface low was weak and easily damped as it moved further NE into the upper confluence zone on the back side of the 50-50 vortex. A bit more spacing there helps, but we need a deep surface low to make this work. The 50-50 feature has been there, and has looked impressively strong. Yes it will vary somewhat from run to run.

Hell no dude. Pay attention. That's not a real -NAO. It was enhanced by an extension of the WAR!