IrelandWeather

I thought I was understanding this west based -NAO more this week from reading posts about it but clearly I'm still stumped clearly! If you have time can you explain why the GFS 12z FI isn't an example of west-based? Say Day 9/10 onwards. High migrates NW to Greenland, but it doesn't stop there and continually moves westward towards Canada (maybe moves is the wrong word, it's clearly weakening/draining away as it pulls towards Canada rather than a strong block moving west). It ends up with SW'lys by the end of the run. Of course, I'm aware it's one det run and FI and will change, but I'm asking more in the sense of 'this is what I thought X was, why am I wrong'. Perhaps others commenting about west-based -NAO, when it is in fact not being shown on any runs, have also confused what it is like me, in the sense of interpreting what I outlined above from the GFS 12z as being an example of it? I'm a novice so literally thought it meant the HP moves westwards towards Canada! TY in advance if you do shed some light on it.

If you run the sequence beyond +140 on the ICON, I don't think you've got it fully right either though? The high over us makes moves towards Greenland (them yellows pushing NW) and then drops SW back over us. It looks pretty clear to me but maybe you are reference the buildup to +156 rather than running through to the end. +156 +180 The ICON still would need the second push of heights to suck our high back NW towards Greenland, as Mike just alluded to. I would agree that +180 chart is still going one way though, as the second push is well on it's way EDIT: Aside, GFS is absolutely stunning.

I'm curious why so many keep saying these are the best early winter charts for years/best start to winter. Was I hallucinating last year? It's been a year. One year since a good start to winter. And the model output for the above began in November too, and there were plenty of runs which showed potential of an even better spell of weather. The charts from last year rival nearly anything popping up currently, unfortunately we just did not get all the hoped embedded features so many didn't see snowy conditions. But still, you can't even argue that last years spell wasn't as good, because this years hasn't even happened yet and could end up even worse (or better, who knows). Some snow, prolonged cold, ice days...coldest spell of December weather since 2010. It's been tossed around so much the last week and it's a bit funny. I wouldn't say it (Dec 22 spell) was classic at all here in Ireland, but given nothing has happened yet it would be strange to say that this is the best start to winter since 2010. But hey, different strokes.

Ah come on with this type of commentary. The GFS was king yesterday because it kept up a positive outcome for cold compared to the ECM 12z and now we’ve picked one out of the bin and placed the GFS there. ECM is good but GFS showing, as the ECM did yesterday, it’s not a done thing.

Well for those who buy into the theory... Last few days has seen quite the uptick in sunspot activity again, with several big sunspots back on the suns face, with 40% chance of M-class solar flares. Prior to that we were in a small lull period.

All this talk about GFS being terrible and 4th - sure, the 31 day rolling value is 4th. But more recently the GFS is coming back to form back no? It's the top ranked one on the most recent timepoint? No? Perhaps I'm reading wrong.