Stormchaserchuck1

There is a lag

Alaska is a big spot. Neutral or negative H5 is going to give you a warmer pattern pretty far north. If the ridge stays over Alaska (probably unlikely) the northern areas will be cold. I'm mostly talking about Dec 6-7->

Why be negative? Things change, you have to be able to change with it. "The MJO forecast way out in time" has done so poorly as a forecasting tool over the years.

That's a +400dm mean ridge over Alaska for a 7-day period. Not really the same as the 1 panel you posted above. We are going to get a -EPO period but it's not going to be as strong or sustain like 2013.

In the bigger picture, it's not really a big deal. It happens rarely. I think the other notable one was in August when a lot of models were warm in the long range and it ended up being cool.

I'm personally not a big fan on long range MJO forecastability. I've seen a lot of times actually over the last 10 years where patterns drastically change when the MJO is projected to go into favorable phases for X.

Come on man.. there is like 1 instance of a ridge leading to a trough in the east coast over the last year, and it's already been posted like 3 times lol. The large scale features held: -epo, +pna. I don't know why it had a big ridge when the Pacific looked like that anyway, but you know long range models hit at about 0.80 correlation accuracy. Especially when 1,000 mile wide features have a strong signal. It's predictable. 2-4 week models are much less predictable, there is a pretty big fall off after 384hr in predictability.

^That's a massive +NAO, MJO. With heights over Alaska neutralizing, we are going to go really warm there. These are large scale features that have a big impact on the east coast. Look at how the ridging in Alaska is just about gone in that 360hr map. If we don't hold that, the cold pattern is going to fall.

What is with these weird hours? 354hr? 306hr? We'll probably get a below average period after Thanksgiving into the first week of Dec as the EPO will be negative.. probably unlikely we see snow though. Then the pattern retrogrades and changes pretty quickly.

You're not going to get a below average temp pattern with that upper latitude and Pacific H5. That's a +2 +nao and developing -pna.. it's going to flux the SE ridge after unless the models are wrong about those 2 patterns. CFS MJO? I'd look more at the plots bluewave posted above.

That's at odds with the end of the EPS. You're posting a 1.5 day old model.

That's a major +NAO. The cold anomalies are from -EPO that happens days before. By the end of the run, it's neutralizing and more of a -PNA is trying to build. There is a few day lag between the evolving Pacific pattern and US Temps. It's pointing to an above average 2nd week of Dec. At 384hr you can already see the SE ridge trying to build.

I think that evolving N. Pacific pattern doesn't match the MJO too well. Wonder if the EPS, and models over the last two days, have it less amped.

^It's what the pattern is evolving into. The EPO is breaking down there, and -PNA is building.. usually that happens over the Pacific at 500mb first then a few days later it effects SE ridge downstream. With super +NAO like that anything unfavorable in the Pacific is going to blast the ridge north going into the 2nd week of December.

End of the 0z EPS is showing a +2std +NAO All the roll forward stuff this year was predicting it for the Winter at about a +0.2-0.3 correlation: - 7 straight +NAO months Feb to August - 8 straight +AO months March to October - Lag from Solar Max 0z EPS mean 360hr:

End of the 0z EPS is not looking good lol

The favorable H5 look for December has slowly degraded on models over the last few weeks. -early Nov models had a persistent -NAO through Dec.. that's really changed to positive around the end of Nov/early Dec -A few days ago there was a strong +PNA on models. That has about disspeared -The -EPO was looking like it would be a strong pattern a week ago. It's still going to happen, but now as strong and persistent as before. By the 2nd week of December it's probably gone The best thing going for us is the Stratosphere warming, which usually "downwells" in +30 days at this time of year... puts a possible -NAO pattern for the 2nd half of December.

Hopefully it materializes. Probably not a given though.

https://www.meteo.psu.edu/ewall/ENSHGTAVGNH_6z/ensloopmref.html 0z EPS has the same thing. NAO is positive Thanksgiving until Dec 6. Now we have a good Pacific during that time, remember 13-14 and 14-15 had a favorable Pacific with +NAO and we did fine snow-wise. The Scan ridge is looking good at the end, but it's more reflecting the warming at 50mb and 10mb.

Warming events don't happen in the Summer. You mean in June in the South Pole?

You don't need a 500mb -NAO to have 10mb warming. Actually history is full of examples where the two are at odds. It correlates +40dm -NAO at Day+0, but a +100dm -NAO at ~+30 days (+25-35 days), which is the end of December. Let's see if we get a 2nd -NAO period later in Dec.

Did he? It was on models, now they have some pretty good +NAO troughing near Greenland with ridging underneath of it on the east coast. I think we are still below average temps though during the ridge because of -epo/+pna at the time.

Yeah it looks like it is MJO driven. The good news is the Pacific continues to act more like "Neutral ENSO" than La Nina. CPC PNA has been positive 21 of the last 29 months, and 12 of the last 19 months since the 23-24 El Nino ended. The 23-24 Strong Nino I believe changed something. I've watched it difficult for N. Pacific ridges to establish and sustain all year. ENSO does correlate the highest in Jan-Feb, but this is a pretty good +PNA now on models for the last week of Nov and early Dec... We had 8 straight +AO months earlier this year. We had 7 straight +NAO months until 2 months ago. The Atlantic side is not in a long term -NAO state, and it's decadal fluctuation index, so the consistency is important. That's why a good month of solid -NAO (2nd half of Nov in December) was looking good! Some change! It's kind of the same pattern happening. Maybe the Stratosphere warming will turn the NAO back negative in the 2nd half of December, but that's because of something, not a default state, which I was hoping for. I still think we see -AO tendency this Winter because of low N. Hemisphere 500mb heights in the Summer and Fall.

The Pacific looks good with MJO going through Phase 7 and possibly Phase 8.. models are developing and have trended toward a +PNA pattern. The Atlantic was looking blocky earlier in the month and that was exciting because it was associated with a Stratosphere warming to help sustain the pattern until possibly early January. In the last few days a big +NAO appeared in the medium range, and the 10mb warmings doesn't look as strong, although it's still a Strat warming happening. We will probably get colder later in the month, but it kind of has a bad taste when the fundamentals were looking so good, now it's just a MJO-amped pattern and nothing more. By fundamentals I mean holding a -NAO for more than 10 days.

Not going to ignore the big +NAO that came out of nowhere the last few days. A week ago models had persistent -NAO through Nov and Dec, and I think I actually made a few comments about how rare that has been. Almost all -NAO's have lasted only 10 days then gone away or switched positive. Well there it is again. Since 10-11, we haven't had a -NAO Winter for this reason, and 19/19 Winter months with NAO value >1.12 in that time have all been positive! That's the decadal phase we're in. It was looking hopeful that this year would start off different, but that's changed in the last few days.