November/December Medium/Long Range Disco

[Bob Chill]

Some very nice tracks in the mix. The flush hits look nice on the panels. Sometimes the gefs memebers have snow but a totally unrealistic way of getting it. There are some really good evolutions in the mix. Nice seeing the southern ones mixed into the spread as well...

[Bob Chill]

Control run is sweet but multiple good ones this run. Long ways to go but at least we have something to track/discuss. 

[psuhoffman]

8 minutes ago, PrinceFrederickWx said:

Most of you already know this, but December was always a wild card and most December Ninos suck. My money has always been on February this year.

Don't sleep on the possibility January is good. Most ninos have a snowy blocky period but a decent number of them it starts in January. January was a big snow month in 64, 66, 78, and 87. Just because February was the winner last few modoki ninos doesn't mean it will be this time.  I don't have the skill to pinpoint exactly when the pattern will align I just look at the analogs and say sometime in January or February we will likely get a snowy period. December is a crapshoot and leans warm even in a modoki nino. 

[Chris78]

11 minutes ago, Bob Chill said:

Control run is sweet but multiple good ones this run. Long ways to go but at least we have something to track/discuss. 

Would definitely ease the pain to score something prior to things going to sh#t. 2 events prior to December 15th would be a huge win  even if we get nothing the rest of December.

[Maestrobjwa]

Just now, psuhoffman said:

Don't sleep on the possibility January is good. Most ninos have a snowy blocky period but a decent number of them it starts in January. January was a big snow month in 64, 66, 78, and 87. Just because February was the winner last few modoki ninos doesn't mean it will be this time.  I don't have the skill to pinpoint exactly when the pattern will align I just look at the analogs and say sometime in January or February we will likely get a snowy period. December is a crapshoot and leans warm even in a modoki nino. 

About that....as I go through weather twitter, there seems to be an opinion by some that this isn't a modoki niño and rather it looks basin-wide...(I can't quite tell, but...I think cranky is among those with that opinion) So uh...is it or ain't it?

[frd]

4 minutes ago, psuhoffman said:

Don't sleep on the possibility January is good. Most ninos have a snowy blocky period but a decent number of them it starts in January. January was a big snow month in 64, 66, 78, and 87. Just because February was the winner last few modoki ninos doesn't mean it will be this time.  I don't have the skill to pinpoint exactly when the pattern will align I just look at the analogs and say sometime in January or February we will likely get a snowy period. December is a crapshoot and leans warm even in a modoki nino. 

Makes sense !  Maybe the best months for total snowfall could be Jan and March. Anything is possible. I like March 1958 by the way. 

 

[psuhoffman]

Leave no puppy alive!!!

[psuhoffman]

11 minutes ago, Maestrobjwa said:

About that....as I go through weather twitter, there seems to be an opinion by some that this isn't a modoki niño and rather it looks basin-wide...(I can't quite tell, but...I think cranky is among those with that opinion) So uh...is it or ain't it?

Last I looked the modoki index was still pretty indicative of a modoki nino. At times past modoki have taken on basin wide characteristics. Look at some of the sst plots from 2002/3 and 2009/10. Very few are the "pure" modoki that some like cranky are talking about with warm Central and cold eastern Pacific. I suppose this might be a difference in how some define a modoki. 

[frd]

14 minutes ago, psuhoffman said:

Last I looked the modoki index was still pretty indicative of a modoki nino. At times past modoki have taken on basin wide characteristics. Look at some of the sst plots from 2002/3 and 2009/10. Very few are the "pure" modoki that some like cranky are talking about with warm Central and cold eastern Pacific. I suppose this might be a difference in how some define a modoki. 

Ventrice always pulls out some interesting Pac stuff

 

 

[Bob Chill]

28 minutes ago, psuhoffman said:

Last I looked the modoki index was still pretty indicative of a modoki nino. At times past modoki have taken on basin wide characteristics. Look at some of the sst plots from 2002/3 and 2009/10. Very few are the "pure" modoki that some like cranky are talking about with warm Central and cold eastern Pacific. I suppose this might be a difference in how some define a modoki. 

Yea, it's not a textbook case but it's really just splitting hairs. For our area we just need to avoid strong or east based Nino's. I'd take my chances of with any other nino versus strong or east based. 

[Bob Chill]

35 minutes ago, psuhoffman said:

Leave no puppy alive!!!

The window checks off some boxes. -AO/NAO are relaxing, active southern stream, solid cold airmass, and pattern is prob flipping to warm. That's a pretty typical combo to get a coastal in our area. All we can hope for is it to hold together as the leads close. 

Would be kinda funny if it ends up a southern slider. Upper air pattern evolution fits that possibility as well. 

[Maestrobjwa]

7 minutes ago, Bob Chill said:

The window checks off some boxes. -AO/NAO are relaxing, active southern stream, solid cold airmass, and pattern is prob flipping to warm. That's a pretty typical combo to get a coastal in our area. All we can hope for is it to hold together as the leads close. 

Would be kinda funny if it ends up a southern slider. Upper air pattern evolution fits that possibility as well. 

No--NOT funny!! Lol

Coming on the heels of last year's torturous run of southern/eastern sliders, and with the pattern flipping this threat window...that kind of southern fail would just be.....mercy. If that were to happen, I would dub that the "ghost of nina 2017"!

[Thanatos_I_Am]

0z GFS looking a little interesting at 174

[Maestrobjwa]

Ha...0z GFS tryin' to muster up something for Day 8

[midatlanticweather]

6 minutes ago, Maestrobjwa said:

Ha...0z GFS tryin' to muster up something for Day 8

December 5th rule 

[Maestrobjwa]

7 minutes ago, midatlanticweather said:

December 5th rule 

Was just talking to my mom about that earlier...that series of years where we always seemed to get something frozen on that day...has it returned? Lol

[yoda]

00z GFS would suggest a nice 2-4 inch storm for Dec 5th lol... h5 also looks pretty nice as well IMO

00z GFS also has a nice Dec 8-9 storm as well

[Scud]

Never risk a pup.....

[showmethesnow]

Looking at the snowfall maps the EPS is still pretty much Meh on the possible earlier storm (centered around Dec 5th). Gets the 1/2" mean through the cities but most of that is coming from a handful of members. As far as the Dec 8-10 possible storm we have seen a very good improvement. Whereas the 12Z mean was showing the 1 1/2" line just through the cities the 00Z now has the 3" line. Seen a good improvement with the number of members showing snow for that time period as well as a handful of heavy hitters showing up. 2 members of which are getting around or over 2 feet of snow through the region.

[showmethesnow]

First chance I have had since my trip to really look over the long range and the PAC going to hell that has some in a panic. Not so sure this is such a done deal as some may think. Now what I have seen may be nothing more then the EPS just delaying the inevitable but I question whether it may be showing us something else.

Below we have the EPS run from 12Z DEC 26. Notice we have a consolidating trop pv setup with the lowest heights anomalies setup over northern Alaska. We see the +PNA shifting eastward and weakening with very little in the way of ridging extending from Russia towards the pole.

 

Now take a look at what the EPS has steadily move towards in just a day in a half of runs. We see a weaker trop pv which has two distinct lobes, one west of Alaska and one over north-central Canada. Notice we are also seeing the +PNA holding on with ridging extending up towards Alaska. On the other side of the globe we are seeing distinct ridging from Russia extending towards Alaska as well. What we may be seeing is that the EPS is moving towards a solution that bridges those two ridges giving us a split of the pv. And looking at the runs they have progressively gotten more aggressive in that regards.

 

 

Now at this point we are not there yet as the latest run does eventually go in the tank later in the run though the look isn't quite as horrible as previous runs. So we could be looking at nothing more then the EPS delaying things somewhat. But if on the other hand we are actually looking at a split of the pv, in its current configuration now shown, that actually sets us up for a good looking PAC as the placement the western pv lobe probably gets shoved over the Aleutians and we would probably see a +PNA as well as a possible -EPO. 

Now ignoring whether we actually see a split or not I will say there is one thing I have seen has been very encouraging over the last few runs. The models in previous runs were looking to consolidate and strengthen the pv over the general local of Alaska and that was/is my biggest fear. We see that and we are probably talking a long time to get rid of that feature and recover from the damage that it would do through the CONUS and Canada. But the runs have been steadily moving away from that idea and moving more towards a weaker pv and holding back a portion of it in central Canada. 

So for those who are panicking at this point, I am not so sure it is worth the effort. It is obvious that the models are struggling somewhat in the longer range and it is quite possible that as the extended moves into range we in fact see a somewhat favorable setup or at least a much better outlook then what was first being advertised.

Note*** GEFS has also seen similar changes though not to the degree of the EPS.

[Ralph Wiggum]

2 hours ago, showmethesnow said:

Looking at the snowfall maps the EPS is still pretty much Meh on the possible earlier storm (centered around Dec 5th). Gets the 1/2" mean through the cities but most of that is coming from a handful of members. As far as the Dec 8-10 possible storm we have seen a very good improvement. Whereas the 12Z mean was showing the 1 1/2" line just through the cities the 00Z now has the 3" line. Seen a good improvement with the number of members showing snow for that time period as well as a handful of heavy hitters showing up. 2 members of which are getting around or over 2 feet of snow through the region.

This period would make sense as the ens has the pattern relaxing right around this time as we transition from BN temp regime and transition to the PAC air push. These are when we usually cash in. The roller coaster look on the ens looks to continue as I mentioned before this may not be a bad thing as transitions usually yield our chances as opposed to just wall to wall cold. 

[CAPE]

3 hours ago, showmethesnow said:

Looking at the snowfall maps the EPS is still pretty much Meh on the possible earlier storm (centered around Dec 5th). Gets the 1/2" mean through the cities but most of that is coming from a handful of members. As far as the Dec 8-10 possible storm we have seen a very good improvement. Whereas the 12Z mean was showing the 1 1/2" line just through the cities the 00Z now has the 3" line. Seen a good improvement with the number of members showing snow for that time period as well as a handful of heavy hitters showing up. 2 members of which are getting around or over 2 feet of snow through the region.

Pretty big jump up on the 0z EPS snowfall mean for days 10-12. That is a significant change from previous runs. Hopefully its not just a blip. That seems like the period with the highest chances to produce a winter type storm before the *possible relaxation* (being gentle and optimistic, lol). I am not giving up on next week though. I think we could still sneak in a minor event midweek.

[Chris78]

33 minutes ago, C.A.P.E. said:

Pretty big jump up on the 0z EPS snowfall mean for days 10-12. That is a significant change from previous runs. Hopefully its not just a blip. That seems like the period with the highest chances to produce a winter type storm before the *possible relaxation* (being gentle and optimistic, lol). I am not giving up on next week though. I think we could still sneak in a minor event midweek.

GEFS still advertising a juicy storm system to our south for the 7-9th time frame. That's several runs in a row now.

My one concern would be that high pressure is building in from the west instead of being in place to the north. I would think that  would possibly favor suppression but I know it's too early to worry much about details...lol.

 

[frd]

Snow cover continues to impress and continues to pile up too acrosss North Amercia !

Considering how slow things started out, very remarkable to see this ! 

 

 

[frd]

Nice animation, looking at this for sensible weather I watch near the 11th to  16 th.

 

 

[frd]

A follow up to the early and mid part of December .

 

 

[Scud]

 

In the voice of Rainman.....

Perturbed, definitely perturbed....definitely....

[psuhoffman]

2 hours ago, C.A.P.E. said:

Pretty big jump up on the 0z EPS snowfall mean for days 10-12. That is a significant change from previous runs. Hopefully its not just a blip. That seems like the period with the highest chances to produce a winter type storm before the *possible relaxation* (being gentle and optimistic, lol). I am not giving up on next week though. I think we could still sneak in a minor event midweek.

I have noticed over the last several years that the EPS really won't show much of a signal on the snowfall means until a threat gets into the day 10 range.  Even in January 2016, there was a hint at the setup on the h5 but the snowfall mean didnt start to respond until it was within about day 10.  The GEFS will often jump of something in the day 11-15 range, and usually its wrong, probably because of its lack of spread compared to the EPS.  Due to its greater variability and numbers, plus the time range, the EPS won't really show a significant snowfall total on the mean in the day 11-15 range even in a pretty good pattern.  Seeing it start to jump up around day 10 when the pattern is conducive to a snowfall is typical.  Still doesn't mean its high probability or anything but its not a bad sign.  

[jayyy]

We’re not even through November and most have seen snowfall (some have seen significant snowfall) and it’s been in the 30s and cold for nearly a week. We will certainly be well under average for the month. The fact that people are panicking because a storm may be rain or mix before winter even begins is ridiculous.

 

Patience guys. Patience. The first storm in December will likely not be a snow maker. The second, however, likely will be as we will have blocking and a -AO. 

[Bob Chill]

28 minutes ago, psuhoffman said:

I have noticed over the last several years that the EPS really won't show much of a signal on the snowfall means until a threat gets into the day 10 range.  Even in January 2016, there was a hint at the setup on the h5 but the snowfall mean didnt start to respond until it was within about day 10.  The GEFS will often jump of something in the day 11-15 range, and usually its wrong, probably because of its lack of spread compared to the EPS.  Due to its greater variability and numbers, plus the time range, the EPS won't really show a significant snowfall total on the mean in the day 11-15 range even in a pretty good pattern.  Seeing it start to jump up around day 10 when the pattern is conducive to a snowfall is typical.  Still doesn't mean its high probability or anything but its not a bad sign.  

The potential centered around the 8th-9th isn't going to be handled well at all. No confluence or hp over the top. That could easily change going forward but for now ens guidance is showing a wave running the gauntlet between a departing hp off the coast and a fresh hp dropping into the plains. If that's how things develop then the precip shield is going to be fast moving and narrow. Not something that any model is going to handle well until the lead time is far shorter. I can see how it can work out but there is plenty of reason to question everything for now. 

 

ETA: the type of event is similar to many that we saw in 2013-14 with progressive flow and waves running boundaries. If anyone remembers tracking those events then they'll understand how tricky they were leading in. We didn't have much confidence in many of those events until they were inside of 5 days and even then they were prone to plenty of swings and wobbles.