Absolute Vorticity

Between the months of April and September, the South Pole averaged a temperature of -61.1C (-78F).

This was the region’s coldest 6-month spell ever recorded, and it comfortably usurped the previous coldest ‘coreless winter‘ on record — the -60.6C (-77F) set back in 1976 (solar minimum of weak cycle 20).

Antarctica climatology journalist Stefano Di Battista who has closely watched and published research on Antarctic temperatures for many years,
points out that for June, July, August and September the average temperature for each of these month finished-up below -60C (-76F) — a phenomenon that has occurred on just 3 previous occasions: in 1971, 1975 and 1978.

Since the PV was so strong over Antarctica this past cold season, I wonder if we'll see the opposite affect for the Arctic, meaning a weak PV? Should be interesting to watch this unfold.

It's funny - all I saw on social media is how Iran had their hottest summer on record......Iran! And we are to trust their thermometers? It gets hot there! Someone tried to post in the comments about the Antarctic chill, but it was quickly squashed as "just an anomaly - temps will surge there this summer!" These people are so into their narrative about global warming and rising seas that they intentionally block what is really happening (i.e. the cold wave in southern hemisphere now).

cloudy72 wrote: ↑Mon Oct 04, 2021 8:12 am It's funny - all I saw on social media is how Iran had their hottest summer on record......Iran! And we are to trust their thermometers? It gets hot there! Someone tried to post in the comments about the Antarctic chill, but it was quickly squashed as "just an anomaly - temps will surge there this summer!" These people are so into their narrative about global warming and rising seas that they intentionally block what is really happening (i.e. the cold wave in southern hemisphere now).

Well stated, Mike! Totally agree with this.

This is quite a cold anomaly thats developed in the GOA. A little bit more along the coast and we have -PDO

A -PDO wouldn't be a total shock since you typically see that with a La Nina anyway. I wonder what effect (if any) that warm tongue to the south of the PDO region will have on the jet? Lots of warmth along the East Coast of the US too thanks to the persistent ridging. Currently, the developing Nina is central based and not East or West based. Nino Region 4 is normal to slightly above (not torching like we have been seeing for years now) and it's not very cold off of Peru either. We'll need to watch that to see if the coldest anomalies continue to be Central based or if that shifts any this Fall.

tron777 wrote: ↑Mon Oct 04, 2021 8:04 am Since the PV was so strong over Antarctica this past cold season, I wonder if we'll see the opposite affect for the Arctic, meaning a weak PV? Should be interesting to watch this unfold.

Was very interesting to say the least. Couple of things I look at is Australia and you have Sydney which is about the same Latitude as Atlanta and Melbourne which is about the same as Lexington,Ky. So you would guess that the weather would be similar in the winter months and that is not true because they have water between them and the antarctic where we have land which can carry the cold much further south. This past winter they were rather mild in Australia for the most part but when the PV weaken they got some really nasty winter weather for them though for the most part short-lived. Like Les mentioned does the opposite happen to the PV in the northern hemisphere and I have no ideal but I do believe in mother nature averaging everything out so this planet can still operate.

tpweather wrote: ↑Mon Oct 04, 2021 7:13 pm

tron777 wrote: ↑Mon Oct 04, 2021 8:04 am Since the PV was so strong over Antarctica this past cold season, I wonder if we'll see the opposite affect for the Arctic, meaning a weak PV? Should be interesting to watch this unfold.

Was very interesting to say the least. Couple of things I look at is Australia and you have Sydney which is about the same Latitude as Atlanta and Melbourne which is about the same as Lexington,Ky. So you would guess that the weather would be similar in the winter months and that is not true because they have water between them and the antarctic where we have land which can carry the cold much further south. This past winter they were rather mild in Australia for the most part but when the PV weaken they got some really nasty winter weather for them though for the most part short-lived. Like Les mentioned does the opposite happen to the PV in the northern hemisphere and I have no ideal but I do believe in mother nature averaging everything out so this planet can still operate.

As you know Tim (and everyone on here LOL) I love most forms of extreme weather (minus the heat obviously ) But anyway, there is always cause and effect in weather. We know that when we have a ridge upstream from us (cause) then there is a trough over us downstream (effect) and vice versa. Like when we talk about Alaska all the time Tim and how we typically have the opposite of what they're getting. If they are warm, we are usually cold and vice versa. So with all of that stated, if the Southern Hemisphere has a strong PV for their Boreal Winter, do we get a weak PV for our winter in the Northern Hemisphere? I am not taking anything else but cause and effect into consideration with this post. That's it. Not ENSO, QBO, MJO, the other Tellies, etc. Only speaking about cause and effect. I'm very interested in this actually. Per modeling so far, the PV is expected to remain weaker then normal. Models are models and the reality will soon tell us the real story in the coming months ahead.

My buddy Jim Sullivan, who I used to forecast long range weather with for Neoweather, well he's a degreed Met these days working at a private firm in NJ. Here are his early thoughts for the winter:

https://jimsullivanweather.com/2021/10/ ... r-2021-22/

Pac continues to cool and I think its safe to say the PDO will likely be Negative for our winter months, with the ongoing troughs along the west coast to continue for a good chunk of the rest of October. Not sure what this will mean in combo with weak LaNina, I'll have to dig into my never-ending bookmarks because I know I have that info, somewhere, lol. But as has been mentioned we don't want LaNina to get into the Moderate strength as I don't think that combo(-PDO) is a favorable one. LaNina is forecast to drop substantially for the month of October in general , I hope with that kind of momentum (which can be hard to stop)it doesn't keep it up into November.

The thing is... since 1950, when we've had a second year Nina, it has always been weaker then the first year. It's never happened in the modern era. So if this Nina does become moderate then it will the same as the mod Nina we had last winter. If it becomes strong, that has never happened either in a second year Nina so yeah, that's why everyone is expecting it to remain weak. Mother Nature of course has the final say.

tron777 wrote: ↑Fri Oct 08, 2021 6:36 am The thing is... since 1950, when we've had a second year Nina, it has always been weaker then the first year. It's never happened in the modern era. So if this Nina does become moderate then it will the same as the mod Nina we had last winter. If it becomes strong, that has never happened either in a second year Nina so yeah, that's why everyone is expecting it to remain weak. Mother Nature of course has the final say.

I hear you, but beware of momentum

Bgoney wrote: ↑Fri Oct 08, 2021 4:57 pm

tron777 wrote: ↑Fri Oct 08, 2021 6:36 am The thing is... since 1950, when we've had a second year Nina, it has always been weaker then the first year. It's never happened in the modern era. So if this Nina does become moderate then it will the same as the mod Nina we had last winter. If it becomes strong, that has never happened either in a second year Nina so yeah, that's why everyone is expecting it to remain weak. Mother Nature of course has the final say.

I hear you, but beware of momentum


Screenshot_20211008-165502_Chrome.jpg

I'm fully aware lol That's what I'm worried about. Makes sense why the latest round of seasonal climate models (Oct runs) have went warmer for the winter. I think they are keying in on a moderate Nina instead of a weak one. Now that doesn't necessarily mean anything because we all know that these climate models are usually crap from 2 months out and beyond. They are generally halfway decent for a month out and that's about it. The November runs will be telling at least for December that is for sure. So with all of that stated... wondering if we get an early start with some fun in Nov and Dec, with favorable blocking and all of that. Then as we progress thru January things begin to change so a 50/50 month if you will, then for Feb, the SE Ridge from hell comes in and winter will be in the West by then. However, from what I've seen March continues to look very good for blocking to return so you'd get winter to go out with a bang prior to Spring's arrival. Not a prediction by me at all, just throwing out some ideas swirling around in my head to get yours, and other people's feedback.

Hey Les and I am like you with many ideals of how things may shape up for winter. We have been in the same pattern for about 3 months or so and we are starting to see changes though slow but changes. I believe winter will get an early start as well and expecting a nice December. First we will need to see that pattern change and it will happen and really hopefully a slower change which imo will help us move towards the early start. Still very early in the season and over the weekend I am going to start looking at Europe and Asia to see how things are developing over there and my guess and only a guess but expecting Europe to end up with some cold weather before us so hopefully I will see that when doing some homework this weekend.

tpweather wrote: ↑Fri Oct 08, 2021 6:40 pm Hey Les and I am like you with many ideals of how things may shape up for winter. We have been in the same pattern for about 3 months or so and we are starting to see changes though slow but changes. I believe winter will get an early start as well and expecting a nice December. First we will need to see that pattern change and it will happen and really hopefully a slower change which imo will help us move towards the early start. Still very early in the season and over the weekend I am going to start looking at Europe and Asia to see how things are developing over there and my guess and only a guess but expecting Europe to end up with some cold weather before us so hopefully I will see that when doing some homework this weekend.

I'm curious to see if some of the guidance that's been showing blocking along with a colder and stormier pattern for late Oct and esp as we get into Nov is right or not. If it's right, I'm going to take that as a good sign that our thoughts for an early start might be correct. If we remain on the more milder side, that could be a red flag. This far away all we can do is speculate and sit back and watch.

This is a tweet from Dr Judah Cohen from a day or two ago about a possible early season disruption of the Polar Vortex. That would make things interesting.

A weeks worth of snow/ice gain

dce wrote: ↑Fri Oct 08, 2021 8:48 pm This is a tweet from Dr Judah Cohen from a day or two ago about a possible early season disruption of the Polar Vortex. That would make things interesting.

It could if the cold air is able to be on our side of the globe. Last winter, we had some good blocking and a weak PV, but the blocking had already set in and the bitter cold air was actually blocked from coming over the pole from Siberia. Eventually, it did lead to that good few week stretch in Feb for the majority of the country. But until Feb, our winter last year was mild without a lot of snow. We shall see if we can get a different outcome this year from the weaker then normal PV.

Bgoney wrote: ↑Sat Oct 09, 2021 7:14 am A weeks worth of snow/ice gain



imsalaska-7day.gif

Departure from normal as of 10/8... looking good S of the arctic circle. Below avg in the actual arctic itself which makes sense due to the blocking and warmer then normal temps there.

tron777 wrote: ↑Sat Oct 09, 2021 9:58 am

dce wrote: ↑Fri Oct 08, 2021 8:48 pm This is a tweet from Dr Judah Cohen from a day or two ago about a possible early season disruption of the Polar Vortex. That would make things interesting.

It could if the cold air is able to be on our side of the globe. Last winter, we had some good blocking and a weak PV, but the blocking had already set in and the bitter cold air was actually blocked from coming over the pole from Siberia. Eventually, it did lead to that good few week stretch in Feb for the majority of the country. But until Feb, our winter last year was mild without a lot of snow. We shall see if we can get a different outcome this year from the weaker then normal PV.

Indeed. When I say interesting, it just means that a little weakening of the PV in October is outside the norm. We wouldn't see any winter weather, of course, but at least it is a very small step in the right direction for an early start to winter.

dce wrote: ↑Sat Oct 09, 2021 11:49 am Indeed. When I say interesting, it just means that a little weakening of the PV in October is outside the norm. We wouldn't see any winter weather, of course, but at least it is a very small step in the right direction for an early start to winter.

I get it Doug. All good bud. Agree with you if the cold can spill over on to our side of the globe then it's game on for sure.

Glad to be back, forgot old password.
Really enjoy the excellent weather discussion here. Lake effect season is around the corner for me. Enough warmth in lakes to produce some wild storms if dynamics come together.

Snowbrain2 wrote: ↑Sun Oct 10, 2021 11:48 am Glad to be back, forgot old password.
Really enjoy the excellent weather discussion here. Lake effect season is around the corner for me. Enough warmth in lakes to produce some wild storms if dynamics come together.

Hey Jeff! Glad you're back! Our old forum bit the dust in late Feb so everyone had to re-create their account anyway. Can't wait to see your awesome snow pics again this winter. With the mild October we're having, Lake Erie should be primed and ready should arctic air intrusions occur.

Yes it's the GFS and yes it's Judah, but we do know that the PV is weaker then normal right now so this has a possibility of occurring. We watch and wait obviously.

Long Range EPS is looking interesting in early November. Watch this animation by Week 2 in Nov. If correct, flakes anyone???