European Winter Outlook 2018-19

Welcome to this winter’s snow outlook for the European Alps. As this comes out, the mountains in Europe are beginning to experience an extraordinary system for the recordbooks.

EC is currently forecasting 4m+, and GFS 8.8m of snowfall. That, ladies and gentlemen, is a 10 day snowfall forecast for 8.87m of snowfall. Regardless of whether it occurs to this full extent, this system could produce a decent amount of the season’s snow accum totals. It seems almost ignorant that I produce my seasonal outlook at the dawn of an incredible event of potentially once in a century proportions.

ENSO

The current general model consensus is for an El Niño event.

As mentioned in previous outlooks, my “official” opinion is for a weak-moderate basinwide Niño event, which I should clarify that I do recognise that the CP Niño domain will be warmer in oceanic sense, than the EP Niño domain. In terms of what this means for Europe, the dominating driver the NAO is more negative under both an EP and CP Niño, so we should see periods of Greenland blocking, and a dynamic North Atlantic jet stream. Evidence points to more snowfall for the Southern Alps, but it is arguable that generally the Alps are colder and get slightly above average snowfall, albeit a bit dry for the Northern Alps. El Niño in general supports more SSWs and a weaker stratosphere, which has been shown with a stronger Aleutian Low forecasted by many models and forecasters, aiding stratospheric warming into winter.

QBO

The QBO is currently descending from negative to positive, with it currently descending between 30 and 40mb.

My current modelling and prediction shows the QBO bringing roughly net neutral influence on the winter ahead, so won’t have much of an influence, given it’s current status.

Solar

This winter, according to current Belgian sunspot modelling, will feature the solar minimum, and reflect a -AO/-NAO influence on the European pattern.

Snow & Ice

We currently have around average snow cover over Siberia, which is expected to be become roughly slightly above average by month’s end. This projects in general a slightly stronger Siberian High to interact with the Aleutian Low propped up by El Niño to create stratospheric weakness. It all connects to each other!

Another thing to link in, is the lack of Laptev-Barents-Kara Ice Cover, which supports a -AO, and Scandi blocking, which is again a precursor of a SSW (Sudden Stratospheric Warming).

MJO & SOI

One thing left to mention, is the potential less Niño-like atmospheric component over Winter. Some modelling, particularly from the better models, the EC and UKMET, indicates a +SOI or neutral SOI, which indicates La Niña and Neutral ENSO atmospheric conditions respectively. What this is saying that the impacts of a Niño may not be what you think. Niño typically suppresses a strong MJO, however I expect an active MJO around Phases 6-1, with cold SST gradients around Indonesia, and warm SST gradients around the Central Pacific, and CFS modelling support. Phase 6 or 7 of MJO correlates with a -NAO. My AAM forecast currently sits slightly positive, which is in line with the MJO and other general forecasts I have made surrounding extratropical features, particularly the Aleutian Low, and also the ENSO Phase, but also recognises the SOI atmospheric forecasts, and that this winter may not feature a fully coupled atmosphere and ocean in the ENSO region. We’ll see….

Model outlooks

The EUROSIPS multi model ensemble, including ECMWF, shows ridging from Scandinavia down to the Alps, but more trough-like for the UK.

The NMME multi model ensemble, shows warm anomalies for the European Alps, and neutral anomalies for the UK. Precip is higher than normal for the UK.

The JMA model (note: for Nov-Dec-Jan) shows troughing for the European Alps, and the UK.

Conclusion

The models in general are looking at more ridging over the European Alps. But personally I am looking towards more troughing over the Alps, because of a -NAO/-AO pattern in general, with only a few issues with that prognosis. I expect in my opinion, an above average season for the Southern Alps, a slightly above average season for the Northern and Western Alps, and an average season for the Eastern Alps. And in general, more troughing and snowfall for the UK and Western Europe, and more ridging and less snowfall towards Eastern Europe/Russia and up in Scandinavia.

Thanks so much for reading.

Seasonal outlooks tend to have bias and errors, due to the fact that these forecasts are so far out. So don’t use these outlooks to make important decisions. These outlooks is meant to be interesting information, that can help to see what the season might be like.

This took a lot of work, so I appreciate your support. Starting in late November, my long range outlooks for the European Alps will start! They will be produced every 2-3 weeks, looking out into the range of 10-30 days out. This season, I will explore climate Drivers as well, including the AAM, MJO and others. Stay tuned.

Thanks again for reading, follow me on Twitter @longrangesnow and subscribe to my email list by clicking on the tab on the main header above.

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