CAPE

An op run snow map at this range is clown either way dude.

The mean is not bad. Temps super marginal verbatim, but it implies colder air coming in as precip is still going(that always works!) It would probably be good enough to get the NW crew on the board for sure.

That's the big difference. The ejecting low has more separation from the trough digging along the west coast and thus is stronger over the central US. Primary holds on too long.

You're doing ok. At this range with a discrete threat on guidance, the maps on the means become more useful.

There will be more and different iterations to come. The 6z GFS was quite different from previous runs, with the initial weaker attempt at coastal redevelopment, then dropping that vort in behind with another attempt over the weekend.

I suppose it's debatable how much value they have at range, but the context of my post in response to WxUSAF's post was more about expectations.

Nice overview of the late week system/potential from Mount Holly in their morning AFD. I now have the generic rain/snow in my forecast Wed night into Friday. LONG TERM /TUESDAY THROUGH FRIDAY/.. Looking at the larger scale big picture, the main story for the long range will be a continuing blocking pattern remaining in place over the north Atlantic. This will help keep surface high pressure dominant over eastern Canada which will also have a tendency to force more of a southern storm track as (as opposed to storms riding up to our north and west). In terms of the forecast details, Tuesday through Wednesday look to remain dry and on the cool side with a continuing northerly flow due to the high to our north. Looking towards late next week, there remains a lot of uncertainty in the forecast especially with regards to a potential storm system. The deterministic GFS really downplays the storm potential as it shears out approaching shortwave energy approaching from the west. Meanwhile the GEM Global, ECMWF, and some of the GFS ensemble perturbations depict a large lumbering upper level trough approaching from the central CONUS with an associated surface low over the Great Lakes giving way to secondary low development off the coast. If this were to verify, it could mean a fairly significant coastal storm affecting the region by next Thursday into Friday. But even then, there are still questions regarding precip types (rain vs. snow) as temperatures will be marginal. The bottom line, late week storm threat still in play but a lot of uncertainty remains in the forecast. We continued to stay close to the NBM with this forecast update and carry likely POPs for Thursday into Thursday night.

Looks cold for Christmas behind our coastal storm.

It's a potential MILLER A!!

Agreed, and posting those ridiculous clown snow maps wont help lol.

I am mostly looking ahead(for my yard). The late week deal might work out for some, most likely inland and north I think ultimately.

It doesn't quite come together in time at the surface for our region but there is more space/less squash, so more coastal development.

On the 6z GFS, the vort that was previously coming in behind the ocean low(50-50) and helping to squash the main wave, now misses and slides SW under the Canadian ridge and comes in behind our wave of interest.

Thanks! Yeah I'm with ya. Although I have become slightly intrigued with the late next week event, I know the setup, the date, and my climo lol. One or more will be the likely cause of failure. With the advertised pattern progression, just beyond that threat- around the 20th and beyond- looks like the best window for much of this region to possibly get on the board. Could be fun in mid/late December for a change.

Pretty nice Xmas eve h5 look on the 18z GEFS-

It's not very useful unless looking beyond day15. The current ens runs go out to the 25th. Also based on the 0z run, 3 cycles ago.

Yeah especially after a month+ of pattern chasing.

Exactly. Perfectly stated.

Ultimately more separation between our wave of interest, and the vortex off the NE coast that is heading for 50-50. Also don't want all of the energy sucked out of the low when it's in the plains, so better timing upstream as well. As always, it is mostly wave timing. All our hopes and dreams are based on quite random events lol.

That's not a kicker though. It's the opposite really. It's so close on the heels that it is absorbing much of the energy from the low(the storm) out ahead of it. That leaves a weaker, strung out vorticity ribbon ejected eastward that is then weakened/absorbed by the vortex off the NE coast.

Slightly off the peak. When will the zero crossing be?

Ok enough of the negativity dude. Your Eagles are 11-1.

The GFS simulation likely isn't the ultimate outcome. That setup at the surface tho. I mean, the wall of HP with the low off the Canadian Maritimes. Goddamn. Slight adjustments..

If this were to be the ultimate outcome, I will take an inch or 2 at this juncture.

Basically the same outcome on the 18z GFS. Not enough spacing between the (would be) 50-50 low, and our wave of interest. Too much upper confluence/convergence on the backside of that vortex and it kills the lift.