Much as I hate to say it, and looking at Stodges Input,
18 minutes ago, stodge said:
Morning all
On we go into February and with the vortex split now imminent and a possible SSW beyond that, more interesting chart watching ahead.
This morning I'm going as far as Monday February 19th.
Starting with ECM 00Z OP at T+240:
Not a million miles away from yesterday's chart at this time and the rapid transition from a strong Atlantic to something much more blocked and amplified remains on course with this model. The Azores HP moves north than north east around the top of the British Isles and into Scandinavia opening the door to a cold ENE'ly flow. Wintry conditions for many especially in the south and east but cold and fine particularly in the north and west. The longevity of this pattern seems unclear at this stage.
GEM 00Z OP at the same time:
After yesterday's little diversion, it's back to more of what we've come to expect from GEM with little sign of an E'ly or anything cold. The Atlantic has slowed but the Azores HP has ridged NE to the east of the British Isles to link with heights to the north of Scandinavia. On the western side of that ridge, a mild SW'ly flow crosses the British Isles so a taste of spring rather than winter for many especially in the south and east but more unsettled further west.
On then to GFS 00Z OP at the same time:
A classic winter chart with LP to the north and HP from the Azores ridging across southern Britain and Northern France. A mild SW'ly airflow with the driest weather to the south while the north remains more changeable with occasional rain or showers. Further into FI and the evolution becomes increasingly messy and quite hard to fathom as the Atlantic slows.
GFS 00Z Control at T+240:
More dominated by LP than the OP but still an Atlantic-dominated chart. Control ends mild with rising heights to the south and the jet being pushed further north.
Plenty of solutions on offer but only 2-3 offering an easterly component at this time. There's a cluster which build the Azores HP north forming an MLB close to the British Isles but others show the Atlantic still trying to come through and with the Azores HP ridging at the same time we get a milder flow over the British isles than seemed the case yesterday.
That being said, by T+336, the number of GEFS with an E'ly component has increased markedly and more so by T+384.
In summary, the new acronym on this thread has been "QTR" for Quick Tropospheric Response. Some have shown we are likely to see that QTR from the vortex split and the Wave 2 attacks on the daughter vortices. Perhaps and ECM this morning supports that but neither GEM nor GFS convince and suggest we could be looking at 4-5 days further before we see a significant pattern change taking us into the last week of February.
I don't know - I do think proponents of QTR have taken a step back this morning and expecting the tropospheric response as early as T+240 from now seems unlikely but the wait may be worth it (or it may not). More runs are needed as always.
From my novices' perspective the unwillingness of the PV lobe over Canada to move and the GEM and GFS favouring a continuation of the Atlantic lows does seem to me to be the most likely outcome.
Model output discussion - proper cold spell inbound?
in Forecast Model Discussion
Posted
Much as I hate to say it, and looking at Stodges Input,
From my novices' perspective the unwillingness of the PV lobe over Canada to move and the GEM and GFS favouring a continuation of the Atlantic lows does seem to me to be the most likely outcome.