The Arctic Oscillation is returning to a negative state and this looks to be the firm trend as we head deeper into November. It also means a continuation in growth of the big snow cover we’ve already got.

ALL things point to a big winter across the boreal hemisphere this year but the big question remains, where does that cold go exactly?

Current hemisphere snow cover as of today.

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It’s highly likely that this almost late Nov/early Dec snow cover extent is forcing more of a -AO and stratospheric warming which normally doesn’t occur until winter but winter is kicking off early in response to that larger than normal snow extent.

No significant change in the positioning of the current strat warming and so there’s no indication of significant cold heading UK/W Europe-bound just yet!

I think it’s only a matter of time before cold visits us. For us to really see winter, we need 2 things. 1) -AO with slackening of the westerlies which opens up the arctic door. THAT’S HAPPENING and will continue to happen. 2) -NAO the ‘trend’ is negative but is currently ‘slight negative’ to slight positive (neutral) BUT given all other aspects, it’s not a question of if but when. The atmosphere takes time to adjust.

NAO may head into a firmer negative towards late November which may bring us the first taste of winter.

The AO should remain negative so this pattern is worth watching!

As stated in yesterday’s video. I suspect many of us could see snow before Christmas the way things are evolving.

ECMWF 500mb 7-day mean heights DAY 3-10.

Temp anomalies

Based all everything going on… THIS is extremely unlikely!!

 

Cold start Thursday morning thanks to a chilly high settling in ahead of the next Atlantic system.

Cold flow today/tomorrow on the backside of the current low is setting the stage. Cooling our atmosphere and with radiational cooling, expect frost in the North tonight but tomorrow night, expect -1 to -3C widely in the North, 1 to -2C in South with -6 or -7C in Highland Glens.

First widespread UK frost Thursday morning.

After this weekend’s low pressure dominance we look likely to have more frost opportunities early next week ahead of another low.

Be sure to watch the video as this may wet your winter appetite…

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