psuhoffman

I referenced the MJO wave in my analysis. But its flying...is going to spend 7-10 days in the MC, it's not stalled and cycling there like previous years. By Jan 20th its exiting into the PAC and heading towards our favorable forcing. An 8 day MC traverse ending around Jan 20th is a really poor justification for "cancel the rest of winter".

GEPS agrees

This is what it actually looked like This is what the ensembles said from 5 days out Good luck trying to do better than that on a 5 day forecast. We KNOW global models underestimate mid level warming with these storms when there is no block and locked in confluence...we knew we didn't have that...anyone who was believing those snow maps from 5 days out and not realizing what was probably going to happen...well that is user error not the fault of the tools. They did an amazing job and I had a pretty good idea what was going to happen from a LONG way out. Like I said they are tools not a forecast, and most who know how to use those tools made pretty good forecasts IMO based on them. Weenie posts in this thread does not mean skilled forecasters actually expected a lot of snow in DC 5 days out.

I know you know, just agreeing...for the benefit of the same audience. Spell check is adding some humor to my posts lately

Since I highlighted the issues with the Jan 17th threat earlier I wanted to say it can work. It would just be a much higher probability if the TPV were located further east. But there is one example that worked with the TPV where the guidance has it, and its from this exact time of year and one of our nino analogs. Jan 22 1987 was very similar and worked out. So this can work, just would take lucky timing wrt the wave spacing, the boundary, and the phasing between the SW and the TPV.

It’s a temporary relax. The winter’s over nonsense was started by that clown Cohen. It’s a temporary response to the MC forcing as the mjo progresses and the epo ridge sliding over into Russia. The tpv temporarily traverses the pole but it’s still weak and will get displaced again quickly once forcing gets out of the MC imo.

If the guidance is right about the progression that’s the one that has the highest probability imo. The wave before it has a shot but unless the tpv shifts east of currently shown it needs a lot of timing and amplitude variables to go right. That look there is more classic for a wide margin of error threat where we can survive more synoptic details not being perfect because the long wave flow is set up exactly right.

There is a reason 50/50 is the sweet spot. It leaves enough room for a wave to amply behind it while also creating a westerly flow just above us so the system can’t cut. With the tpv west of there we have to play a balance act. Too strong and it squashes the wave. To weak the wave cuts. It’s a legit threat. But as shown a tenuous one. I’d be honking like crazy if we see that tpv trend closer to the canonical spot. Otherwise as shown it’s not a setup I’d feel good about until much closer leads because of the delicate balance being played there.

Details matter. That would be perfect if that tpv in Quebec were moving east towards 50/50. But it’s retrograding. Unless that gets further east than even the euro has it, we run the risk of a cutter or suppressed and are left at the mercy of timing and trying to tread the needle with the wave along the boundary.

We are in a -pdo so it’s easy to just “blame the pac” and we’ve spent long stretches of the last 8 years when it was the pacific. But I’ve seen troubling signs when it wasn’t. example look at the pacific long wave pattern there. Trough west of AK. Epo ridge. But the trough dumps west. Here… same. then… opposite configuration and it floods pacific puke across. So if both possible long wave configurations don’t work….no matter how the pac is aligned the trough dumps west. The wave lengths just shorten to do it. The only way lately we get a +pna is when there is a trough just off the coast flooding warmth across the whole country so that does no good! Imo the Atlantic is just as much to blame. That high constantly off the southeast resists a trough moving east. The wave lengths just shorten so the energy digs even deeper west. Even when the pac is aligned there seems to be resistance to a trough diving into the southeast. It’s not been impossible. We’ve had some periods that knock down the war. But it seems to be a bigger part of the problem that gets talked about.

Gfs was close. But again it stalled another wave before getting to where we need to cut off the WAR. If A was at B instead that would have been a HECS. It would give more room for the next wave to amplify and at the same time turn the flow over top of us to block a the next wave from continuing to gain latitude. basically it would promote a more amplified wave to try to come at us from the southwest while at the same time having it hit a brick wall in the TN valley and force it to turn east under us. That’s our big snow look. But so long as these tpv waves keep stalling under the block then rotating back and not progressing east under it into 50/50 it leaves the door open for the next wave to cut. Im not saying it’s going to do that. Just saying until one of these systems gets into the 50/50 and severs the war nao link the next wave is likely to try to cut if it amplifies.

This happens every crappy year. Usually right after the last legit threat for snow fails in late Feb or March. Seems we’ve skipped to that part of the annual cycle already.

Ok so we’ve reached the “scorched earth take no prisoners” part of the season already.

Omg yea! But I think maybe I wasn’t clear. I’m not saying that wouldn’t work. Look at that pac. It’s Fng perfect. And that +nao is displaced and elongated south to mimic the same effect as a nao 50/50. Not quite as effectively so it’s not as big a hecs look but that would be a snowy look. What I was saying is it’s unlikely we get that. Getting that pac look is gonna be hard enough in a -pdo cycle but to then also get that super rare elongated nao trough with a tpv in Quebec… I wouldn’t hold my breath to ever see that as a 2 month long locked in pattern again in my life was my point. On the other hand if we do get that kind of pac look we don’t need a crazy -nao. But i disagree we want a +nao either. 2015 only worked because of that odd elongated configuration and that’s not how it would likely play out again. But 2003 and 2014 snow we can get by with a neutral to decent Atlantic look and a perfect Pac. 2003 2014 While both years might have had a numerical +nao at times the h5 shows the Atlantic wasn’t hostile. The configuration was just displaced from a canonical -nao but we would all know that look was good and it’s not what you think of when you say +nao! Those looks can work just fine. But I don’t agree w chuck we want a big blue ball over the nao space. It never worked before 2015 and hasn’t since. That was a fluke imo.

@CAPE @Stormchaserchuck1 I would be thrilled if we got a run like Feb-Mar 2015. There were two storms in there I consider big. One in Feb and one in March. But I think 2014 and 2015 are awful examples of something to root for. I’ve called them fools gold. 2014 Dec to early Feb there was a lot of ridging over the top of the nao domain but because a strong. Tpv got trapped under it the pattern mimicked a -nao. We also had a perfect pacific that held for months which is just unlikely in a -pdo. March 2014 and Feb-March 2015 was a bad example because a tpv got displaced into Quebec. Extremely anomalously SE. and that also mimicked the suppression of a -nao 50/50 configuration. But in 75 years of records that I looked at of snowstorm after snowstorm there are barely any other examples of that. The fact those were our most recent cold snow Winters I think creates the bias that those are a viable long wave pattern to root for. History suggests they were flukes with very specific and rare details that made them work. imo it’s unlikely we will ever see that again in our life. Not saying we won’t ever see a epo pna driven snowstorm. But it’s unlikely we ever see a winter where that pattern leads to repeated hits and a seasonal win.

Since I can already hear the groaning when I say legit big snow I don’t mean hecs 20” storms. But what I mean is a legit amplified wave that drops 6” plus over a larger region wide area. Not some progressive wave that has a significant snow zone of 3 miles wide and even if we get lucky enough for it to how our area many will still be left unhappy. I’m talking about storms like…all 3 of the 1987 storms, the Jan 1988 storm. The late Dec 1990 storm. The early Feb 95 storm. Several 96 storms other than the blizzard. The Jan 2000 storm. Early Dec 2002 early Feb 2003 late Feb 2003 after the blizzard. Jan 2004. The back to back late Feb early March 2005 storms. Feb 2006. March 2009. The two storms right before snoemageddon in 2010. Jan 2011…. Storms that have a BIG areal coverage of snow because they tracked at us from the SW amplifying but were resisted by blocked confluence. That’s how we get a real wide win.

Thanks captain obvious. But a +nao isn’t exactly working either. Baltimore hasn’t had a 6” storm in 8 years! So assuming I want a BIG snowstorm and not just try to get lucky with more progressive waves..what do I want? With a +nao unless we get incredibly lucky with a well timed tpv rotation over the top there is nothing to suppress and prevent an amplified wave coming at us from the TN valley which is our big snow track. The only way we snow anymore is when we just get super lucky to have some progressive boundary wave take a perfect track by pure luck. What look to we want to give us a good chance for a legit Big snowstorm if you’re rooting against a -nao? What other mechanism can work?

Never mind

You’re arguing semantics. You were upset the epo was fading but it wasn’t a helpful epo was my point.

Not a pro but imo it depends how the mlk weekend likely cutter system evolves. If the TPV all dumps east suppression. If too much dumps west cutter. Ideal would be a split where 75% comes east but it hangs some back to later swing under and become an amplified threat.

Even if the block dies completely around Jan 20 I think it’s temporary. If the epo ridge does migrate to Siberia it will force the TPV there up over the pole. That could temporarily cause a +AO/NAO. But as the mjo gets into 6-7 it will re establish the canonical Nino pac which will also likely vacate the tpv again given how weak it and the coupled SPV are. I don’t think we go positive and get stuck there. Even if we did if the pac ridge gets established we can rock 2003 style and aim stj waves at us with lots of cold around. February still looks on track to me. Everyone knows I’ll say when I decide it doesn’t. I think he is worried about the setup after. We do want more of the trough to slide east when it elongates or splits. We don’t want the stronger piece dumping west. That could set up another cutter.

I don’t think the stronger epo ridge on the euro is a coincidence. @Stormchaserchuck1 this is what I was talking about yesterday. Historically that epo should be good. But lately the more that ridge pumps instead of the downstream trough spreading east it digs more SW in response. It’s happened over and over and over. If that’s true we’re better off with the flatter gfs ridge there.

Gefs is old tech. That’s my story.

That’s perfect. You see the handoff happening around day 12. That’s a big dog setup.

I fear that first wave after the likely mlk cutter is probably suppressed. It’s not 100% but that’s a really suppressive look in general and it would take a really significant SW imo to work. Or for the look up top to relax which can happen but we’re discussing how they look now now how they might look later. (I haven’t looked at anything yet today). I was looking at how both set up what imo could be our best shot before some kind of relax/reload of the whole pattern. That might be just beyond where the ensembles end as the tpv in the 50/50 relaxes. I’m slightly troubled that the block is fading so fast. But that could be error. We want the block to relax but it needs to hold somewhat until the flow becomes less suppressive after the cutter that finally pulls the trough east. I thought last nights gefs run set up that period better. It also was set up better for the wave in the 15-20 period imo so it was just better imo. But eps wasn’t bad. Just slightly off on some important details which will change some anyways and could become what we need easy.