Stormchaserchuck1

9 day lead though.. I'd rather see what their forecasts looked like 3-6 months in advance.

I'm not picky about this stuff.. I would say that it was a good forecast because it got the West coast ridge, and half of the below average trough. Usually they are at least near by what happens with forecasts.

Southern Hemisphere AAO so far this July: 1-Jul-25 1.8937 2-Jul-25 2.248 3-Jul-25 2.8385 4-Jul-25 3.1945 5-Jul-25 2.5837 6-Jul-25 2.1543 The correlation is pretty cool.. right at 90N the following January

Phoenix being so hot for a long time last Summer was an accurate predictor... they broke their record streak of most consecutive 100+ days by 40! The other years that had the streak broken came out with a +PNA and -4f to -5f in the Midwest and East for December and January. I don't think they are as warm so far this Summer, but it is warming there always. Also, the AAO last August was record negative.. that rolled forward at 0.5 correlation to a -AO Dec and Jan.. again, something that hit. The PDO was strongly warm forecast, and that got blown out...

Seasonal models were actually really bad over the PNA region last Winter.. they maybe over-use the recent trend and ENSO.

CPC doesn't have a super warm Winter forecast right now.. seasonal models going a little cooler is probably why.

Down near Baltimore and DC it was a snowy January. I had snow on the ground pretty much the whole month. They had a 8-10" storm further south than I think another 6" storm.. it snowed like 15 days through the end of January.. not a horrible Winter. I understand further north it was drier, but sometimes early in the Winter the STJ is further south.

How did it snow 10" in Florida? How did Valentine, Nebraska hit -31F when it was almost March? I was on this board saying that the pattern wasn't good for snow last February and that it wasn't going to snow.. I would dig it up, but there were like 10-15 posts about this in the Mid Atlantic forum. The NAO was south-based positive and there was High pressure in the North Pacific over the North Pacific High position. Plus it takes some time to detox the heavy -PNA/+AO that was the time before. Not a big anomaly. The big anomalies were Dec 2022 and March 2023, but teleconnection patterns aren't 100%, and sometimes other things dominate. Doesn't mean it's always going to be like that. I think we are going back to -NAO cold in the Winter time as Jan 2024 and Jan 2025 had this. The coastal SLP correlation is 5-6x greater in -NAO/+PNA than +NAO/-PNA. I should dig up those old posts... was saying it wasn't a great H5 pattern for snow that 5-7 day models were showing. We didn't have things at our latitude that were favoring cold and snow like a 50/50 low and NE N. Pacific low pressure. bluewave by your posts I would surmise that you are saying NYC is going to average 15"/snow/yr from here on out. No matter, regardless. I don't think that's going to happen... we might have a tough few years with the flux of some things still being unfavorable, but weather patterns wax and wane.. eventually we will enter a better pattern, and the global warming isn't that advanced yet.

Looking hot in the Northeast for the hottest 2 weeks of the year, on average. 12z EPS

SST feedback doesn't make sense to me. Seems like kind of a simple answer. The tropics have recently shown a good SST correlation though with tropical systems. It works in the tropics, but not really in the upper latitudes.

Why are the mid-latitudes warming though? It might just be a pattern that fluxes up and down, with general global warming.

12z GFS ensemble mean at 384hr is trying to bring back the Aleutian ridge and Northeast US/SE Canada pretty major ridge.

Yeah, it's been a +WPO pattern

Actually some big changes in the ENSO subsurface over the last 2 months.

It's not often that you see the cold anomaly max (Iceland) exceed the warm anomaly max in the Northern Hemisphere! (Although the relative value of Europe ridge because it was further south is greater).

Really some extreme QBO swings lately

Well there's a lot of variables included. This is one of them. I posted some pretty cool PDO stuff a few pages back.. you are right, the later into Summer you go the more important some things are. A side note, but I do really like cold 500mb in any form.. I said this last year. We had almost the same exact strong +AO happening at this time last year, and it was the first time we had a cold 500mb sustained area in long time, I think the whole 2020-2023 period didn't have that. I was saying how it could possibly flip the EPO to negative for the Winter, and we did in fact have some -EPO driven cold. All these composites of best snowfall DCA seasons have cold 500mb all over the N. Hemisphere in the Fall before then.. it doesn't matter so much if there is PNA etc. just that there is widespread 500mb cold. I think it's a new pattern that we entered into last year.

I'm going with a colder than average March, and probably above average Dec-Feb.

There's enough data where it works as per the correlation coefficient. It's /1 so 0.1 is +10%, or 55% chance. 0.3 is +30%, or 65% chance. 0.5 is +50%, or 75% chance. Etc.

To test my theory of "evening out", let's see what the AAO does in the first half of August this year. This was last year: 2024 8 2 -3.455 2024 8 3 -4.415 2024 8 4 -4.459 2024 8 5 -4.338 2024 8 6 -4.279 2024 8 7 -4.152 2024 8 8 -3.808 2024 8 9 -3.399 2024 8 10 -3.415 2024 8 11 -3.595 2024 8 12 -3.506 2024 8 13 -3.395 2024 8 14 -3.511 2024 8 15 -3.040 Edit: It's suppose to hit +3 in the next few days, which it usually doesn't deviate from +1-2. Maybe there is a little bit of general time leeway too.

The roll-forward regression for February looks like what we saw mid-Winter last year.. big +NAO/-PNA. Last year also had a very big +AO May-July so it makes sense that it shows something similar

Jan - March 6-8 months after a +AO July Looks like there is tendency for a -EPO March.

Thanks Roger! Very interesting. Fun contest. Good to see everyone doing pretty well.

Invest is 50% in the 7 day.

I think Portland hit 116F.. not 100% sure though.