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Pattern December, Make analogs relevant again

Just a friendly reminder the EPS at the same time frame :D
eps_t2m_anom_noram_240.png
 
I think this storm really needs to be watch if it gets hung back towards Texas. If the upper-low doesn't form until Christmas day, then it should allow the hammer to drop while the low starts moving and give the SE at a fighting chance
 
Stormsfury said:
Well here's what you would want for a massive arctic dump with such a strong -EPO.

https://www.weather.gov/ddc/December1983ArcticOutbreak
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1, The Euro has a very similarly strengthed 5800 m -EPO ridge in a very similar location as this 12/1983 outbreak link shows.

2. Furthermore, that was at about the same time in Dec and ENSO was VERY similar.

3. In addition, the EPS has the MJO going into a favorable path for SE cold (low amp 8). It was also favorable then being mainly low amp phases 2,3 and 7 though low amp 8 is even more favorable on average.

4. The PNA is progged to be neutral vs it being -PNA then. So, better now vs 1983.

So, items 1-4 are very encouraging and tell me what could happen in the extreme.

5.*** The fly in the ointment is that the GEFS prog for AO is modestly + vs it having been solidly - just before the 1983 cold plunge into the SE although this index then drops to neutral.

6. It has the NAO neutral in 7-14 days vs it having been solidly - just before the 1983 cold plunge into the SE.

So, items 1-2 are similar and 3-4 even more favorable than 1983. But items 5-6 are less favorable. Can items 3-4 being more favorable be enough to offset the less favorable items 5-6?

The moral of the story is that the last 10 days of this month remain more uncertain than a typical period 6-15 days out as the extremely jumpy models have shown. A strong and long -EPO can do wonders even into the SE (see 1/2014, 1/2011, 12/1989, 12/1983, 2/1968, 1/1963, and 1/1960 for non-El Nino examples) if other factors are supportive like the expected favorable MJO. However, an ugly SER can absolutely ruin the party like many GFS runs have been showing. I think that there's reasonable hope that the GFS is out to lunch, mainly because of its MJO forecast being at odds with the more accurate EPS, which has an MJO favoring a trough/cold in the E US, but we'll see.

**Edited several times. Last paragraph is newest.
 
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These models are just a huge headache. I think it was more fun back in the old days when you got all your weather info from tv.
 
Why do people keep saying the models are always showing a good pattern 10-15 days out? Did the southeast not just have an historic snow storm? And in early December no less. I didn’t even get more then dandruff flakes but I’ve been well below normal for all of December so far. Yes we are going to warm up for a while but that happens for periods almost every winter. The way people are talking on here you’d think we’ve been torching all month with no snow.
 
The last 10 days of this month remain more uncertain than a typical period 6-15 days out as the extremely jumpy models have shown. I think that is largely because of the extremely anomalous -EPO being progged though Webb's point about the typhoons has to also be considered.

A strong and long -EPO can do wonders even into the SE (see 1/2014 (snowjam), 1/2011 (very cold with major SE winter storm), 12/1989 (very cold and just preceding the great SE coastal snowstorm), 12/1983 (extreme cold), 2/1968 (very cold/wintry), 1/1963 (extreme cold), 1/1961 (very cold/wintry). and 1/1960 (very cold) for non-El Nino examples) if other factors are supportive like the expected favorable MJO. However, an ugly SER can absolutely ruin the party like many GFS runs have been showing if too persistent energy is concentrated in the SW US (either with main trough or as a cutoff).

I think that there's reasonable hope that the GFS is out to lunch, mainly because of its MJO forecast (moderate to high amp 6-7) being at odds with the more accurate EPS, which has a much more favorable MJO that favors a trough/cold in the E US via low amp phase 8, but we'll see. Fwiw, the JMA agrees with the EPS' MJO and says the GEFS is out to lunch. I've been following the various models' MJO progs for years and the EPS usually ends up much closer when they are so far apart. The above notwithstanding, it would obviously be helpful if we could have a -AO and/or -NAO. We actually could still be quite cold in this situation even with a neutral PNA (12/1983 actually had a -PNA though that -EPO is the strongest on record) though a more +PNA could only help the chance.

PS Edit: I forgot to mention that the QBO analogs favor a cold Dec. That could only help I'd think.
 
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I dont even remember the snowstorm the other week being talked about like this is over a week out

Just saying lol its still so far out to Christmas in the forecasting world
 
I will agree that we have absolutely no idea what this system will look like in 9 days but one thing I can almost guarantee, the SER isn't going anywhere anytime soon. This is the new norm around here
 
Not to mention the same models were analyzing now were completely lost when it came to the last snowstorm

There i feel better :p
 
Brent said:
I dont even remember the snowstorm the other week being talked about like this is over a week out

Just saying lol its still so far out to Christmas in the forecasting world
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Well, this time we're talking about Christmas time. I'm sure a lot of people are very curious of what their weather will be like on Christmas. People need to be patient. I'm thinking the models won't have a solution until 2-4 days prior to the event like the last winter storm.
 
Hopefully by Monday we will at least know to what extent the SER will play a role and how far southeast the cold pentrates. Surely 7 days out we will have a clearer picture.
 
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