psuhoffman

Tomorrow for me lol

It's all on the table... where the TPV sets up, where the block over the top of it is (new wrinkle) and how the energy in the flow underneath interacts and ejects. And those are way too many moving linked parts for the guidance to get this nailed down at any kind of long leads. This is more of an inside 72 hours kind of setup, which I know is frustrating but it is what it is.

GGEM has that centered back near Hudson bay with a block over the top, more of an AO block than NAO but with a TPV over Hudson that's actually a really good configuration. And it leads to snow. Let's just hope the GFS is wrong with parking the TPV right on top of us, but it's probably good that its only the worst model doing that right now.

was it overrunning? lol just kidding

Inject the GGEM right into my veins please

Historic snowstorm for the deep south. We will see...

There have been very few permutations among all the ensembles and op runs that have a hit from both the 20th and 22nd threats...They are linked. If more energy comes out with the wave on the 20th the 22nd is likely weaker and south. If more energy holds back at the tail of the trough, the 22nd becomes a more amplified wave and a threat but the 20th is likely nothing. It's likely one or the other. There is a narrow thread the needle balance of energy that could lead to two hits but its not the most likely outcome.

Yesterday this tendency (and duality of options) showed up in the EPS snow plots. There were smaller hits around Jan 20 and larger ones around the 21-22 for the members that had a slower more amplified solution with that wave.

And before anyone screams about "Kuchera" I checked...the ratios are realistic. Actually slightly less than 10-1 along 95 and about 13-1 in the higher elevation areas further from the rain/snow line. This seems very reasonable.

It's always a little risky when guidance has a threat window but has yet to identify a singular wave as "the one". That mean looks great but its from 3 possible hits in a 7 day window, each of which is only like a 30% probability of being anything, which is totally fine and normal for that range, but our odds of an actual hit go up significantly once guidance locks into a singular synoptic threat and more than half the ensembles and op runs start showing a hit with that specific wave. We just aren't inside that range yet though. For now this is about as good as it gets IMO in terms of an identified window of opportunity. We still don't know if its the thing around the 20th or the 22nd or that thing way out around the 25th...but we have several shots in a defined window and just have to hope as the details come into focus one of them becomes a legit threat.

One change has been a trend towards one more round of -nao around day 7. This perhaps increases the chances of a bigger storm but it also means it would take a larger amplification in the flow to get a storm at all. This would apply to the Jan 20-22 period. The -epo TNH still looks to take over after that.

My misunderstanding is because most of that snow on those ensembles I posted is from overrunning but you said “I guess the overrunning is off the table”.

I mean for most of the last 8 years we would have killed to have a 10 day snow mean (days 6-16) look like these. But ok.

EPS has a bit of a signal there now too

NS wave over the top running interference

It would be funny after days of everyone worrying about suppression it’s ends up a cutter. Lol But not surprising. In an epo driven pattern with no blocking a NW track is the way more likely fail.

I think some are imposing the trends from recent and current blocking regime onto the next epo tnh pattern. I get it. I do. But that’s a mistake. Things are much more likely to trend north in the coming pattern than they were with a -3 AO NAO block and a huge arse cutoff 50/50 spinning southwest of ideal.

The EPS definitely shifted south and favors the Richmond area for the biggest threat around the 21-22. But it’s one run. The ggem is further north and 95 or even slightly NW is for target zone. And it’s still far enough out that small shifts run to run shouldn’t be over reacted to.

EPS continues to delay the retrogression at range.

You complain less than anyone else about snow. I’m almost positive he was referring to someone else.

People point out every example of when the gem busted but the gfs is even worse. Not sure why the perception reality gap. ETA: plus examples of gem busts prior to their core upgrade ain’t really relevant

I think he was talking about someone else