Henry's Weather

finish the maps through new england or you'll be banned ... lol. his words, not mine

Pull the plug @ORH_wxman

Are we starting to lean towards a favorable Feb as well? I feel like I've seen periods of strong high latitude blocking persist longer than initially progged, and especially with some kind of stratospheric interference supporting this kind of pattern. Might be wishful thinking at this point. Slow to come, slow to leave? Though I guess the -NAO part of it arrived on time.

Pretty happy with this so far, although as typically happens for me, I assumed the pattern would flip before it did. Maybe push back both those threats 4 days?

I think this would be the kind of pattern to get a category 3+ nesis event in, whether miller A or B. Powder keg, quite literally.

What happened in 08-09? Memory is fuzzy as I was quite young.

That's a great look. I love it when the 540 line is back across the Great Lakes during winter storms.

Transition to a blocking period is gonna be tough for the models I'd think. Perhaps this is a gross understatement haha

I get this from an operational forecaster's standpoint, but from a snow lover's standpoint, this pattern still holds serious potential, no? Even if the models can't handle the huge artic anoms and even at risk of suppression, this has got to be a better pattern than what came before it. I do notice that large PNA ridges produce more consistently around here than periods of blocking.

How's the SSW coming? Is it legit? I assume that affects Feb more than Jan if so.

If I had to guess, I'd say this system has a good chance of missing us all, but I think the lower mid-atl has the best shot. Going to be marginal temps though.

I think I understand why this happens (referring to the s/w in Ontario): Two areas of HP merge near Labrador, "squishing" a portion of that 50/50 low down south. I finally understand what @Typhoon Tip meant. I actually suggested this in my long post a few days ago, but back when today's event was progged to strengthen, it kind of rammed the higher heights northward, towards more favorable places. Another consequence of that scenario would've been no Ontario s/w, because the H5 energy of the cyclone would be more tightly wound (again, the new term isohypse can be used here) and thus, no stragglers to be squeezed off the main low pressure.

Such an interesting look on the GFS. It looks like the remains of our "storm" today eject a pinball s/w which dives through Ontario as mjo781 mentioned. I think that even if that s/w wasn't there, there still would exist too much traffic upstream (or downstream?) in the PAC, which prevents a strong ridge from popping out west, which would itself cause the s/w to dig more and therefore, turn up the coast sooner. Also allows for potential northern stream interaction, stealing the snow from our mid-atlantic neighbors once again. Is a block over Labrador really THAT much worse than a block over Davis Strait?

Seeing it categorized helps to put this storm in perspective. Solid, once-a-year event for the NE but nothing extremely special outside of the death deform band. Thanks for posting.

Pretty clear-cut southern stream SECS/MECS on analogs, which makes sense given the slightly southernly location of that block, as tip mentioned.

Illustrates the risk that y'all in the mid atlantic might be slightly better situated for this one

Why? There seems to be sufficient wave spacing to allow some downstream ridging. It seems workeable to me, a non met...lol.

GEM is a pretty messy setup and still almost scores. Slow dancing s/w under a massive block. That would be one hell of an angular momentum problem.

Holy crap. That's seriously legit, strong s/ws. Anyone have Jan 2015 H5 maps handy? Just curious, I though that one was similar in terms of polar stream s/w location. Manitoba origin.

Maybe shades of March 2018 with each progressive storm having more cold to work with? I guess this December's period was like that too.

We just seem to have no damn cold air. I'd like to believe the PAC improves but that seems to always be 10 days away.

You can see the impact of no deep PAC ridging here. The anomalous arctic rips apart the polar vortex and the cA air becomes cP as it's displaced southeastward, but without a PAC assisting, it just kind of dies on the east shore of Hudson Bay. The GEFS and EPS are in lockstep with this idea. So a great pattern for storms, but not much cold available?

16 days out is a long time for small differences to manifest themselves

Long post: It does seem like this blocking pattern isn't perpetually 10 days away on the ensembles, as both the EPS and the GEFS bring out the purple coloring at hr 96. Of course, it isn't immediately in an ideal location. I wonder if there's much precedent for blocks moving north instead of retrograding west as I've often heard about. Looking at both the american and the european suites, it does seem like maybe the path is NW, so some sort of a compromise. To my eye, it looks like this miller B Jan 4th storm bombs out near Newfoundland and sort of runs into those higher heights like a battering ram and pushes it NW? I'm not a scientist, so I don't know much of the physical processes involved. Wisdom says that our best chances occur at the formation and dissolution of these blocks, with the best chance at the dissolution, as some modified cP air has usually been dislodged south at that point, which is what I believe happened with our 12/16-17 storm? So, this wisdom leads me to assign Jan 8-9 and some time mid-late January (maybe the 18th-20th) as the most legitimate threats. I'd be interested to see if this verifies. We also seem to be southern stream dominated at first, with northern stream chances improving if we somehow get some PAC ridging going on mid-month. I think most in NE would agree, with the exception of some far SW Connecticut people, that Manitoba Maulers forced under a block is a much preferable synopsis to a southern stream event. Anyways, someone correct me if I'm wrong, but we haven't had actual sustained -NAO conditions in January for quite some time. According to this table I snipped off of CPC's site, we haven't averaged a neg NAO in Jan since 2010 and 2011, and obviously, we know the history of those winters. Many of us prefer one of those to the other, but the point remains that we haven't seen this kind of stuff in a while. I wonder if we can actually pull it off. edit: I can recall 2016, before the blizzard, having something like -4 SDs AO conditions, so I'd assume there was some extended period of -NAO there as well

Typical caveats apply, but that is a monstrosity of a ridge out in the plains for Jan 8th threat. Shame there seems to be a s/w diving in from Canada that stops a mature evolution from happening on this particular run.