CAPE

There are definite differences in the character of the ridge across Greenland at that point. If you read my somewhat rambling post yesterday about all the interactions between waves over time, it is nearly impossible to discern cause and effect. In this case I think 'in phase' interaction with NS energy will tend to pull the low further NW.

Some key differences influencing the track of the storm between the GFS, and Euro/CMC: GFS- Has more interaction with NS energy rotating down around the vort near Hudson, as well as energy digging in behind associated with the next trough. Euro/CMC- Most of the NS energy near Hudson is shifting eastward out ahead, and also more separation from the digging trough out west with more of a ridge between.

My wag at this point is that this will end up favorably, although maybe not all snow, for places inland and further NW in our region. For the lowlands it looks more problematic because of the marginal temps. Given the advertised lack of HP to the north on guidance, even a track along/just off the coast would be iffy for eastern areas. This has been a notable issue in recent winters in marginal cold situations.

I am not predicting it will be. I just thought the most likely way we fail would again be a NW track. The setup is clearly better than what we have had, but the block is just getting established. The location and timing of the NS vorticity across southern Canada is going to influence the track of the wave and there are still differences there, and then there is the next western trough with additional upper level energy digging in behind, also impacting the track. Always issues. We still can't know yet.

These poor people. Snow on the ground continuously since early Dec. Never get a break! They never salt the roads there though- just scrape it every other day and continue on. No bother.

Atmospheric wave interactions are so complex and interesting. Just sitting here (a little high) animating and analyzing the differences in the pattern evolution that lead to the different outcomes between the GFS and Euro. There are many (rather subtle) interactions that can be visually identified that lead to significant differences later, but determining the exact initiating 'causes' are literally impossible, as waves are constantly interacting and upstream/downstream is relative in a hemispheric longwave pattern. Then there is the matter of how far back you want to look in time to try to identify what features (and differences in their character) may be influencing any differences in the ultimate outcome later on. Fascinating stuff and yes I do this as an exercise a lot during winter lol. Probably a good one for weather weenies trying to gain an intuitive understanding of a complex process.

(Predicts Ralph will like this post)

That vorticity lobe over the southern end of Hudson Bay needs to pivot eastward sooner. It is in phase with the ejecting southern wave then digs in behind and tugs it north.

I could never do PBP. I have WB.

Somehow it lost its way after HH Thursday. This will be the run where the GFS gets its mind right again.

Come on Americans.. you can do it.

Yeah the CMC ens was beautiful.

lol how sad. Same here.

Snow on the beaches again. Just looked at Rehoboth Beach Cam. Coming down good there.

Basically just snow tv here. Had a period with some decent sized flakes and it started to stick in shaded areas, then went back to super light stuff. Radar doesn't look too encouraging, unless further south.

Some seriously perfect timing wrt to the NS energy overtop. Not too behind like the GFS to tug it NW, or out in front. Just right to let it track underneath, with enough space to not dampen the wave. Not very cold, but the thermals are likely going to be an issue for this period.

Sold. Close the curtains on winter after that.

Some small flakes in the air here now. 34.

See my previous post. Too broad-brush to say the 'NAO/50-50' are causing suppression, when it is really the timing/location of a specific piece of energy associated with what's going out west that is the primary problem.

The vortex over Hudson, which was ejected from the digging trough out west as the Aleutian ridge reamplifies, is a primary 'issue' and will influence the outcome. The 0z Euro phases it into the low off the Maritimes, creating a consolidated 50-50 low. It is the only run lately that gets that vorticity into a position where it won't negatively impact the southern shortwave. On the GFS that energy tries to phase in behind, and tugs the low NW. The CMC and ICON have that vorticity shifting east towards the Maritimes, so it is just out in front of the southern wave a bit and interferes by placing it in the wake. Imo the 0z EURO idea would probably work- get that energy eastward into the 50-50 space sooner.

It's all random wave interactions and timing. Has to work out just right for our dreams to come true.

The block (ridge and 50-50) is just getting established there. But if it makes you feel better, sure it's the NAO. At least you have something tangible to point to for your suppression fears.

That's not what's happening though. There is a parade of vorts across Canada being spit off from the massive trough digging out west again. The one over Hudson Bay is spinning off vorticity lobes. With all this chaos, odds are the NS is going to destructively interact with the southern shortwave in some form- whether tugging it too far NW or dropping the hammer on top. The 0z Euro has the case where all that junk is cleared out and consolidates into a 50-50 with HP behind it. That would work. It probably won't hold either. This isn't a classic NAO block set up at this point, and it is being hindered by the hostile Pacific. As PSU said, lots of timing and luck needed for this to work out

Once you learn to interpret Chuck speak, there is often some good stuff embedded in his posts.

Suppression.