Model Output Discussion - Early November Onwards

[johnholmes]

HI All, would the cold being shown for for Russia be unusual for the time of year if it varified?its just that i cant recall seeing any of the purple shading that far south of the arctic before,normally deep blue and further into winter.

remember those c'olours' are indicative, see the table on the right, of the predicted temperature at 500mb (18,000ft approximately), although they are usually a reaonable indicator of temperature levels below that height. Take a look at the 850mb values and those being predicted for the surface.

[nick sussex]

Some further encouraging signs this morning that the UK will eventually wave good bye to these mild conditions, however theres a very long way to go before then.

The first move to a change is the eastern US trough which allows some pressure rises over Greenland, the next obstacle is making sure that troughing near the UK fills out quickly and sends some energy se into Europe to cut off any chance of higher pressure in the Med pulling the ridge se.

The ECM just about does this however we are talking post 168hrs. Overall there is a signal for some higher latitude blocking but as yet the models aren't sure what to do with it, the clearest way forward which could act as a trigger is a further amplifying trough out of the eastern USA, if this happens then its likely to pull that cold over Scandi westwards as more troughing develops there.

If we don't get this then as long as theres energy undercutting the high it should turn colder but probably dry.

Overall a good start to the day for those looking for a change but keep an eye around 168hrs, we have to see some energy cutting into southern Europe.

[johnholmes]

remember those c'olours' are indicative, see the table on the right, of the predicted temperature at 500mb (18,000ft approximately), although they are usually a reaonable indicator of temperature levels below that height. Take a look at the 850mb values and those being predicted for the surface.

And no nothing unusual for deep cold to be penetrating Russia in early November. Read about the German advance into Russia in WW11 for an example or further back about Napoleon?

[wolvesfan]

Thanks John.

[Matty M]

The 6z GFS is extremely different to the UKM and ECM as early as T120hr

Macro differences in detail towards Iceland/Greenland

[nick sussex]

As we can see how important that eastern USA trough is to heights over Greenland, the GFS 06hrs run pushes it east not ne which flattens the jet as theres no WAA to help build that pressure.

The GFS has been very inconsistent with its view of that trough, it had looked to come on board last night but we're back to some more uncertainty this morning.

Again its hard to have faith in it when the ECM and UKMO are supporting the amplified troughing.

[shedhead]

As we can see how important that eastern USA trough is to heights over Greenland, the GFS 06hrs run pushes it east not ne which flattens the jet as theres no WAA to help build that pressure.

The GFS has been very inconsistent with its view of that trough, it had looked to come on board last night but we're back to some more uncertainty this morning.

Again its hard to have faith in it when the ECM and UKMO are supporting the amplified troughing.

Indeed Nick - we may need to be careful what we wish for here, it's won't take much of a shift to see a zonal pattern setting up.

[Cheshire Freeze]

Aaaaahhhh and the rollercoaster is off for another season. Great signs by the ECM but I'm not getting excited until the GFS is on board- like it or not it's a major forecasting model that can't be entirely dismissed and was the first model to pick up on height rises in the first place. Fingers crossed it falls in to line with a pattern such as the 00z ECM later on......if it does, we're off!

[bluearmy]

tbf, gfs is bound to be the first model to show anything deep in fi as its the only model that we see running at that timescale. even if the initial trough isnt sufficient to promote WAA, i suspect there will another one to follow. i would caution against those seeing wintry conditions this side of the final third of the month. 'slowly, slowly, catchy monkey' as they say in Borneo !!

[kold weather]

OK I'm going to close this thread and start a new one for the new week.

New thread here: