CAPE

NWS Mount Holly is in overall agreement- A shortwave trough along the subtropical jet will eject out of the Gulf Coast region and lift across the Mid Atlantic. An associated area of low pressure will strengthen as it moves through the southeast and up the Mid-Atlantic coast Saturday and into Sunday. The exact track of this surface low will determine what specific impacts there will be. It is worth mentioning that the latest deterministic guidance has shifted slightly further offshore and leaned towards a weaker system overall, potentially allowing for a slightly colder solution, albeit still not enough for an "all- snow" solution. With that said, we can expect guidance to continue the "tug-of-war" of where to place the center of this low, thus it remains in our best interest to stick closer to the consensus blend, which continues to show a low track that gives our higher elevations along the I-78 corridor the best chance for snow with a highly uncertain precip type forecast for the I-95 corridor and points south and east. Guidance should come into better focus in the next 24-48 hours as the shortwave trough responsible for this system moves over the western US and can be better sampled by upper air observations. Bottom line, this system bears watching and is setting up to bring heavy precipitation, gusty winds, and potential coastal flooding though with strong onshore flow. See hydrology section below for more details regarding rainfall and flooding potential.

I've been there before in the snow. It's great. Not been since just before Covid, but sadly I know the story of places like that that didn't survive.

Getting there Chuck. Moving towards it Chuck. Hey Chuck, well.. you know.

GEFS is finally getting there. Note the lower h5 heights shifting eastward into the 50-50 region. Legit block setting up like the EPS.

lol thanks. I'm good. If this winter goes as expected, the last 6 weeks or so of met winter should make most in this region happy. Otherwise, I chase. Kinda thinking about hanging out in Gettysburg this weekend.

There is certainly still some volatility at this stage. State Collège went from 10" at 12z to less than 2 on HH GFS. One more proportional shift SE might do the trick.

The pattern starts to look favorable prior to this, but this period(and going forward) should be our wheelhouse for potentially bigger storms with cold air in place. A classic look across the HL region, with an ideally placed and strong west based block, and a TPV underneath. EPS has been consistent in depicting this pattern for several runs.

The 12z GFS run yesterday was further south and colder. The low was 990 mb as it came off the NC coast. That run fringed PSU. Ofc that NS energy was in a good spot on that run w/more confluence, thus a colder and somewhat suppressive outcome.

Absolutely. Just look at the last 4 runs of the GFS and the shifts that occurred wrt the NS energy I was referring too. No reason to think the final outcome is suddenly nailed now.

Wave timing was always going to be especially critical in this setup, given we don't really have a block in place yet, and the antecedent air mass is only marginally cold. Several of us said it, I think you were one- the 50-50 needs to be a beast, but it also needs to be in a good spot to have the HP strong enough and not retreat too quickly.

I mentioned this in the other thread this morning, and to me its a big problem on the GFS- the timing/depth of the vorticity over eastern Canada phasing into the 50-50 vortex has changed over the last few runs. The confluence it created was key to the strength and position of surface HP over SE Canada as the storm approaches, facilitating weakening the OV low sooner, and allowing the coastal low to strengthen more south of our latitude.

lol at the whole jinx thing on a science based board. It is time for a thread. The threat is legit, and it keeps this thread from getting too cluttered.

6z GEFS is acceptable. Colder and continues with a more SE track than the op.

Watch the NS energy across eastern Canada moving into the the 50-50 region. That needs to dig more. The last few runs it has been flatter, thus less confluence and a somewhat weaker surface high that retreats a bit. The timing/interaction there is an important factor for places further south and the coastal plain imo. Increased confluence would encourage the low to track a bit further south.

Storms would track NW with the trough in that position though. This is where it would really get good for the MA as advertised. More mature NA block with lower heights shifting into the 50-50 position, and the Aleutian low is in a better spot with a ridge building towards the western US. If this is real the latter part of Jan is gonna be interesting.

Sipping my last 120. Looking really good for the NW crew, and it remains to be seen for the lowlands. A bit tenuous. Last 2 runs of the GFS are perfectly acceptable though.

HNY! I think it may be a struggle to get anything to track underneath for the mid month period with a trough centered more in the west/central US, but just beyond that things look much improved, especially if the EPS is more correct, with a west based -NAO, TPV pinned underneath, and lower h5 heights shifting out into the 50-50 region. Significant improvement on the Pacific side too.

Good 'trends' on the 0z and now 6z guidance. Still a close call for I-95 and east, but now looking favorable for a mostly snow event just west of there. That surface HP over SE Canada is in a pretty good spot and stays locked in.

Big difference is with the main shortwave. Way less NS interaction so not as amped. Timing of the waves is much different this run.

Only KUs

LOL HNY Ji.

NA confluence FTW.

This isn't rocket science lol. You run a weather FB page and don't know this basic stuff?

Da fuck? I am all about dat shit.