Snowy Hibbo

It’s certainly interesting the next few weeks, the prospect for cold and snowfall for the next few weeks is very much alive for the UK, or at least parts of it. Afterwards in February, it’s very much at a juncture. On one hand, we have the MJO Phase 3 pointed out by @Singularity, and signs that the SSW forcing is going to wear off later in the month, which would possibly be destructive for the current -NAO. However if we stay in the current GWO phases that have been supporting the -NAO for a little while longer, and see the tropospheric polar vortex stay weak into Feb, we might see that period for possible cold and snowfall extend a little more into next month. But yes, it must come to an end at some point, it’s just a matter of working out when.... More here: https://longrangesnowcenter.net/2021/01/14/europe-on-the-long-term-14th-jan/

Got some decent heat flux into the SPV. It’s just a matter of whether it’s enough for a technical SSW. At the end of the day, it’s just a technicality and ultimately it’s about whether it’s impacts whether a SSW or just a moderate weakening can be seen on the surface in the NH circulation. And the fact we are already seeing a -AO phase helps.

It’s interesting that we already see quite a -AO in the troposphere, before we even start to see the plausible effects downwelling to the surface. So the dynamic there could be interesting. It’s quite possible that we might have the troposphere try to briefly balance itself out, as the SSW occurs, returning to neutrality or even a slight positive in the first week of Jan. Before the SSW comes down to the surface on the 2nd and 3rd weeks of Jan. And you should be able to maintain a mostly cold -AO/-NAO look through there.

https://longrangesnowcenter.net/2020/12/20/europe-on-the-long-term-20th-dec/ Climate drivers looking interesting for a cold and snowy late December and early-mid January for the UK, with the potential of a SSW or similar, good extratropical conditions and an already negative AO in the troposphere

Maybe, this was my take on it: Probably the worse analog (for snowfall) I found on the search for the outlook. Certainly the QBO is the biggest trouble for this winter, but then again it has been all over the shop in the past few cycles, one cannot really know where it will go.

https://longrangesnowcenter.net/2020/12/01/european-winter-outlook-2020-21/ This recent more decent Late Nov/December pattern that is coming into fruition has certainly made the winter forecast more complex, with a number of factors favouring a milder winter. So I have gone for an average to slightly above average snowfall forecast for this winter (in the UK), not expecting a horrid winter or an incredible winter, but hopefully a half decent one. Thanks all

https://longrangesnowcenter.net/2020/10/20/october-preliminary-2020-21-winter-outlook/ Looking like for the European winter IMO: Moving onto Europe, we see a colder December for the UK, and a pretty average winter overall, with a weaker backend of the season. The Northern Alps (Northern Europe) should see an average snowfall season, maybe slightly better than normal. The Southern Alps (and the rest of Southern Europe) should see a slightly below average season, with the best conditions early in winter. Climatic factors: A basinwide moderate (possibly strong) La Nina this winter. A positive QBO Solar Minimum Atlantic SSTs favourable for a +NAO North Pacific SSTs favourable for a Aleutian Ridge. Average growth of Stratospheric Polar Vortex into winter, potential for SSWs later. Phase 3-6 MJO centred tropical base state Low sea ice in Barents-Kara Sea. Average snow coverage in Siberia. Technical analysis in link above :)

At this stage of the game, no news is good news. Average allows for a large spread of potential options, depending on what the climate does. Looking at the clues we have: Tropical upper stratosphere is currently colder than average, that indicates a stronger than normal Brewer-Dobson circulation, pushing ozone towards the NH Strat polar vortex. So again we certainly have the capacity for inducing a SSW, it's just whether the tropospheric factors allow for it.

My first seasonal prediction for the NH this season: https://longrangesnowcenter.net/2020/09/06/early-september-seasonal-2020-21-winter-preliminary-outlook/ Western & Central US and the Northern Alps to benefit from a Canadian Vortex/Aleutian High and +NAO driven weather outlook for the winter ahead from the preliminary look of factors (still got more to loom at in coming weeks...). Not so great for the Southern Alps or Southern Europe in terms of snowfall, and a pretty mild and wet outlook for the UK on the cards. Take a look at the details above

https://longrangesnowcenter.net/2020/02/23/europe-on-the-long-term-23rd-feb-2/ My final forecast for the long term in Europe this season. The final days of the month and first 10 days in March look a little more hopeful for snowfall prospects according to models and the tropical drivers. But this will subside in mid-March. At the end of the day, the season was not that great, and the drivers failed to get us into a conducive state.

The positive AAM anomalies are resuming in the extratropics (at a similar latitude to the UK), which is partially behind the continued and now reinforced +NAO flow. In order for the UK winter pattern to be changed, we need those tropical +AAM transports to move north and -AAM deposits establish close to the poles to help to dislodge the strong tropospheric polar vortex. Looking at the top chart’s upward trend, which shows a strengthening stratospheric polar vortex, we are running out of options, except looking towards a consistent zonal outlook. However later in February may be more interesting in terms of the strat. More details here on my blog for UK/Europe: https://longrangesnowcenter.net/2020/02/03/europe-on-the-long-term-3rd-feb-2/

My latest outlook doesn’t exactly bear very well for the UK, until perhaps mid-late February: https://longrangesnowcenter.net/2020/01/07/europe-on-the-long-term-7th-january/ A little snippet about the current GWO forecast, more details in the outlook. “The GWO is currently in Phase 8-1, and is forecast to proceed through the lower phases of GLAAM orbit over the middle two weeks of January. This is likely to keep the current +AO/+NAO phase in a holding pattern, waiting for the next GWO cycle through the positive phases. The past cycle has been so far inadequate in getting the momentum deposits in the right areas for a less zonal outlook. Positive cycle is expected in late January/early February Frictional torque is currently negative, showing the ability for a negative orbit for the GWO, with the Mountain torque expected to follow“

Yeah, last week of a December looking better and the first 10 days of January. I’m not promising anything, it’s just the drivers look more conducive to better cold and snowfall risks.

https://longrangesnowcenter.net/2019/12/16/europe-on-the-long-term-16th-december/ Some -NAO prospects over the next few weeks, propped up by the -GLAAM orbit. Then a +NAO forecast over much of January, per the descending SPV and it’s currently strong status. Potentially another turn to a -NAO in February, on the back of another GWO cycle and a potential SSW. Details of my outlooks in the link above

https://longrangesnowcenter.net/2019/11/14/european-winter-outlook-2019-20/ Here is my European and UK winter seasonal forecast for 2019-20. We should see a troughing and more snowy pattern in January and February, with a more average pattern in December IMO. Thanks everybody

The current snowy pattern is due to an underlying base state that is still quite negative in terms of AAM and a tropical state which is more progressive in terms of the expansion of momentum. The combination of a MJO Phase 6-7-8 progression and the underlying negative momentum anomalies have introduced Scandi blocking and potentially -NAO (+ 10 days) responses to the brief tropical momentum progression. You can see the meridional pattern induced by the negative momentum anomalies in the medium term by the polarised difference between the block and the trough. Anyway, today I have also released my seasonal winter outlook for the UK and Europe here https://longrangesnowcenter.net/2019/11/14/european-winter-outlook-2019-20/ Playing with ideas presented in the short-medium term applied to the seasonal forecast, as well as looking at stratospheric and other factors in terms of applying it to the likes of January and February.

I’ve just been going around and around in circles with the European forecast. It’s a bit all over the shop. I can concur with your idea though, something I have been mulling over. My European forecast for the season should be out later this week

As @Met4Cast uses in the chart above, there is a significant cold anomaly right in the middle of the Atlantic. So that could help spur the -NAO and a colder winter for the UK. This isn’t the final forecast, this is just the last one I do for the entire globe, hence the global charts. I do a specific final UK/Europe forecast, where hopefully I have a bit more stratospheric guidance. But yes I am banking on a SSW at some point. I do see perhaps a good chance for some strat warming in November/December though. And there’s plenty of factors supporting the potential for a SSW anyways.

You beat me to it! Thanks @Summer Sun Snow & Ice conditions good for Eastern US, Japan and Europe/UK. MJO largely good for European and UK snowfall, perhaps less so later in winter. Similar for Eastern US and Japan. Oceanic ENSO good for Japan, Southwest US and Eastern US. -AAM good for Europe, Eastern US and Japan, less strong later in winter. Stratospheric conditions favourable for Eastern US, Japan and Europe/UK. Solar minimum favourable for more snowfall for Eastern US, Japan and Europe/UK. Atlantic favourable for a snowy UK winter and colder Europe. QBO favourable for Eastern US, UK and Europe. North Pacific favourable for Eastern US, less so for PNW. All this is good for a snowy winter IMO, contrary to the models (yes I know, bold, but I have the reasoning to back it up :) ).

For example, have a look at this -AAM analog I used. Showing some potential for a -NAO/Greenland block, with the trough lying over Europe, but still with potential for a cold winter for the UK. Though this is just one driver/idea.

Chill out. The UK could see a -NAO pattern that would bring a colder winter for it and the rest of Europe. I did discuss Europe in the outlook. It explored the different model solutions heading towards a winter +NAO, and then I explained why this may not be the case.

Take a look at my fresh seasonal outlook. Looking at a +NAO in the models and a -NAO in some of the drivers. https://longrangesnowcenter.net/2019/09/27/late-september-northern-hemisphere-2019-20-winter-outlook/ Early, good season for Japan, Eastern US and Europe. A decent season for California, a poor season for the PNW, Colorado slightly above average perhaps. Early Siberian High development, with a potential SSW later in the season. Nina-esque atmosphere, cool neutral-weak oceanic La Nina. EDIT: Please use the Seasonal Forecast Thread to respond/discuss this forecast. Thanks. BW. https://www.netweather.tv/forum/topic/72635-the-seasonal-forecast-thread/?do=findComment&comment=4084894

Take a look at my fresh seasonal outlook. Looking at a +NAO in the models and a -NAO in some of the drivers. https://longrangesnowcenter.net/2019/09/27/late-september-northern-hemisphere-2019-20-winter-outlook/ Early, good season for Japan, Eastern US and Europe. A decent season for California, a poor season for the PNW, Colorado slightly above average perhaps. Early Siberian High development, with a potential SSW later in the season. Nina-esque atmosphere, cool neutral-weak oceanic La Nina.

In terms of the 2019-20 Winter Outlook, so the countdown begins: https://longrangesnowcenter.net/201...-seasonal-2019-20-winter-preliminary-outlook/ Some ideas here: A strong winter Aleutian low A +NAO favoured by models and Greenland ice cover. Perhaps some -EPO blocking A warm neutral ENSO state. A good outlook for Japan, Northern Alps and Western North America An opportunity at a decent winter for the Eastern US, per some indicators. And probably a wetter and more mild winter for the UK. That said, there is a good environment for SSWs, so we might see more -NAO like conditions later in the winter As for Dorian, per the UKMO and EC, it should move up the coast, rake the East Coast, Georgia, SC and NC. Gets quite close to the Carolinas on both models. And quite deep too.

In terms of the 2019-20 Winter Outlook, so the countdown begins: https://longrangesnowcenter.net/201...-seasonal-2019-20-winter-preliminary-outlook/ Some ideas here: A strong winter Aleutian low A +NAO favoured by models and Greenland ice cover. Perhaps some -EPO blocking A warm neutral ENSO state. A good outlook for Japan, Northern Alps and Western North America An opportunity at a decent winter for the Eastern US, per some indicators. And probably a wetter and more mild winter for the UK. That said, there is a good environment for SSWs, so we might see more -NAO like conditions later in the winter.