Believe it or not a full-blown SSW in the next few weeks took a back seat for a few days as signs of a wave 2 warming event in the right place at the right time became the main source of excitement over the past week.
For that, the strong U.S. low in 5-6 days time needs to coincide with a decent high over Greenland while having the right angle (S to N or SE to NW) to drive warm air right onto the plateau. ECM and GEM meet this criteria, ECM days 6-7 and GEM days 8-9, but UKMO and GFS have the low angled more SW-NE which pushes most of the warmer air across the SW tip of Greenland - not good enough for the warming event.
This also has big impacts down the line, as the SW-NE angled low acts to flatten the Atlantic pattern days 7-10 while the S-N or SE-NW angled low maintains a more amplified Atlantic flow.
The results are clear to see when contrasting ECM and GEM with GFS for the 7-10 day period.
As for the shortwave shenanigans in the Atlantic, we still see a wide spread of possible outcomes, with UKMO and GFS showing the more southerly track with a quicker northerly but ECM and GEM showing a more northerly track which takes longer to deliver any results... but increasingly it appears that the more amplified upstream pattern connects with this slower evolution, so we are left with a choice of fast but short-lived results or a slower but longer-lived reward.
Yes, it is a bit frustrating when the models initially find a faster route and then it turns out to be far more complicated, but that nearly always happens, and we are still working with only the first of the really significant opportunities for a cold spell to develop that we've encountered this season.
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T-Max: 30.2°C 9th Sep (...!) | T-Min: -7.1°C 22nd & 23rd Jan | Wettest Day: 25.9mm 2nd Nov | Ice Days: 1 (2nd Dec -1.3°C in freezing fog)
Keep Calm and Forecast On