ORH_wxman

Forgetting about next week’s system for a minute, the EPS continue to trend too toward a colder start to December (and very end of November) This is actually looking a lot colder from a hemispheric pattern perspective than even a few runs ago. We’ll see how it looks as we get closer but this would likely be an interesting pattern to follow in early December if it maintains.

Sell the clown maps hard on this type of setup. Mountains in VT/NH would do ok but lower down would struggled unless you really crank omega and this far out that’s gonna be iffy…esp with somewhat weak thermal gradients. You worry about disorganization in precip field. Plus, still a chance the whole thing ends up further north. I still think there’s a good chance for some flurries and snow showers around the ULL on the weekend though. Many have a good shot at first flakes.

Interesting that the GEFS keep trending towards this -WPO/+EPO/-NAO look to end November and start December. The +EPO sounds bad but it’s not because of the -WPO is still able to supply arctic cross-polar insert into the PJ…this is something @Typhoon Tip and I were discussing some last year…how even when we got brief bursts of favorable EPO, a staunchly positive WPO was really being a turd in the punchbowl helping so many colder patterns underperform. This time, it could help if the ensembles keep trending that way. That pattern would be fairly interesting around here I think to start December.

Even if it tracks a touch north of us it’s still a cyclonic flow with lots of clouds/snow showers/flurries. So yeah, unless it tracks way north, I’d still feel decent about many getting first flakes. I’m not talking accumulations. We’d need it tracking south of us to really talk about accumulating snow outside the upslope spots.

Decent chance of first flakes for many next weekend with that deep ULL moving overhead. Prob no accumulation but the novelty is always there on first flakes of the season. No true arctic cold in sight until you flip the EPO/WPO region (broken record the last 2-3 winters) but you’ll at least get some seasonably coldish weather for a few days when you have a ULL like that overhead.

The year is 1990. Bruce Schwoegler just issued a forecast for 3-6" of snow. You immediately flip to channel 7 to see if Harvey Leonard is on board. He's similar but slightly less....3-5 inches is his forecast. You can't believe your eyes. We might actually get enough snow to cover all the grass blades and even shovel? You quickly change the channel again to channel 5 to see if Dick Albert is matching the other 2. Instead, it's Mark Rosenthal who is filling in that night. He says you might wake up to it "snowing to beat the band" and is forecasting 4-7". You almost faint from happiness. We're back to the dark days of our childhood.

Ensembles are trying to cool things down Tday week. Nothing crazy but at least cold enough that you’d might get a threat if you lined up some synoptics. Euro weeklies from last week were still a furnace though right through the first 10 days of December, we’ll see if they change today.

BDL was prob around 15" in 2001-02.....really awful winter, but 3" is laughable. Even at BDL. The only places that have plausibly experienced a 3" seasonal total in New England are maybe some of the beaches down on the south coast of CT....esp really close to the NY line.

First flakes for some of the peaks today/tonight and possibly tomorrow. Upslope flow and midlevel temps cool to bring snow down into the highest terrain.

The empirical evidence would argue against a death spiral. We would’ve continued to get large declines and instead it’s basically been flat since the nadir 2010-2012 period. The evidence also argues against a rebuilding of multi-year ice to levels seen pre-2007. We seem to be more in a semi-stable period of sea ice the last decade-plus. I suspect we need to warm more in the winters in order to see more record lows consistently. (This is because winters are still cold enough to refreeze the first year ice into its max thickness of roughly 2m) Until that happens, we’d need a big time preconditioning weather pattern to get a new record.

Looks like 2.47 may have been the min. Up to 2.58 million sq km as the central CAB low-concentration ice is refreezing now.

Area is down to 2.47 million sq km....not sure how much further we can drop given the likely refreezing of the central CAB commencing where there's a lot of low concentration ice right now, but if we can drop below 2.42 million sqkm, then that would beat 2016 for second place.

Gonna need that Aleutian ridge to get poleward....if it can, then we get that nice -WPO to a neutral or negative EPO combo....and that will help give the arctic shots some bite to them so the airmasses aren't as stale. In recent winters, aside from the annoying deep western troughs, we've had a lot of +WPO which kind of gives us fake arctic airmasses even when the EPO goes a bit negative or the PNA goes positive. Obviously last year was an El Nino, but the La Nina of 2022-23 had this pattern....despite a -EPO and strong arctic ocean blocking, we had deep troughing over Kamchatka and far eastern Siberia which you don't want to see. You might be able to get away with that if you had a decent PNA, but once you add in the deep west coast trough, it was game over. I know @Typhoon Tip and I have had discussions about the stronger WPO/Bering sea ridges being a good cold signal (and the opposite being a very strong warm signal). I've often talked to @CoastalWxabout the Bering Sea death vortex too....low heights there really suck for us. In those colder La Nina years like '08-'09, '10-'11 and to a lesser extent '07-'08, we had the -WPO present with the big poleward Aleutian ridges....'07-'08 was kind of a hybrid, the meat of the Aleutian ridge was south but there were vestiges north of Bering and into the arctic ocean almost acting a block (esp in Dec 2007).

We had a pretty favorable pattern for preconditioning from late May into mid-June but then it got less favorable late in June....you really want to sustain it longer to have a run at 2012. Still, it was enough to put a top 3 melt season in play as the data showed in my July post. 2012 was exceptionally well-preconditioned. It had like a 300k lead at the end of June on SSMI/S area compared to the cluster right behind it in the rankings which is a huge spread.

I meant to post this 3 weeks ago, but got very busy....but the prediction for the final NSIDC sea ice area based on June data is below: This graph is what the final NSIDC area would be if you took the NSIDC data from 6/30 and then use each of the below season's melt from 7/1-onwards. This gives us a good range of possible outcomes. For example, if we used the record-breaking post-7/1 melt from 2023, we'd end up at 2.31 million sq km which is 2nd lowest of all time. Note how 2012's post-7/1 melt does not produce a record....the reason is because 2012 was already so low by 6/30 that it did not need record post-7/1 melt to produce the lowest minimum on record. That said, while post 7/1 melting has not seen the type of trend that pre-7/1 melting has, it is still faster than the pre-2007 era. If we took all years in the dataset for our post 7/1 melt, then we'd get a mean of 2.96 million sq km for our min. But if we took only post-2007 years, we'd get a mean of 2.74 million sq km which is where I would concentrate my prediction. July has been a pretty solid loss month, so it might be lower, but I'm going to base this prediction on what the data said on 7/1....which when we round to the nearest 100k, will be 2.7 million km plus or minus 300k. (so a range of 2.4-3.0) Right now, NSIDC area is barely above 2012 and 2020. but they both dive off a cliff pretty good soon. 2012 goes completely nuclear so it will be hard to keep pace...especially since forecasts show a reverse dipole that just set in the past day or two continuing for at least another week. So I'd expect 2024 to start falling behind the pace a bit....but there is still a very realistic chance for a top 3 or 4 season. 3rd place is 2.58 million sq km in 2020....4th place is last year at 2.62 million sq km. If we're gunning for 2nd lowest, it would be 2016 at 2.42 million sq km. I usually like to predict NSIDC extent too though it's a bit harder to do that because compaction plays a big role in extent (but not much for area)....however, given the prediction of 2.7 million sq km for area, I'll go with a minimum NSIDC extent of 4.0 million sq km plus or minus 400k.