Model Output Discussion - Early November Onwards

[kold weather]

With October out of the way it is now time for usw to focus on what November will bring. Are the models suggesting a similar sort of pattern to what we've had in the previous two months, or are there hints of something different coming up?

[johnholmes]

the above chart i Compare it to the one for now=very little similarity it seems to me in its shape or the area it was/is in.

I have no idea how this correlates to any way of predicting what the MJO may do even less what that may mean for weather 2-3 weeks down the line.

Anyone?

http://cawcr.gov.au/...Last90days.html

the link above shows how it is now-I hope!

Edited November 3, 2011 by johnholmes

[Wales123098]

Winter is starting to appear in FI wonder if we'll end up with a similar end to November as last year.

[AWD]

GFS 12z has the 10c Isotherm over south east england on Monday, plus more notably, one massive split of the Polar vortex north of Scotland!

The -5c Isotherm dissappears of the chart as it's so far north!

[Summer Sun]

Winter is starting to appear in FI wonder if we'll end up with a similar end to November as last year.

I doubt it, I see it been a case of more of the same for a while yet, yes it will turn cold enough for forst and fog but anything on a par with November 2010 will be very unlikely.

[Aaron]

I doubt it, I see it been a case of more of the same for a while yet, yes it will turn cold enough for forst and fog but anything on a par with November 2010 will be very unlikely.

Nobody expects us to have the coldest last 2 weeks of November on record again, but snow in November ain't rare.

[kold weather]

Pattern change will not be a cold pattern if it does shift, that atlantic trough has been sitting for a long time out there and any cold airhas long been moderated out.

IMO we are still a solid 2 weeks from any cold pattern, what is more key for now is trying to shift the pattern to something abit more progressive IMO.

[Snowmad79]

All the models are presenting nothing but teases in FI and this seems to be every run. I remember us have to clutch at straws for the odd colder Synoptic a couple of years ago where as lately FI seems to be full of colder synoptics every day.

Clearly the models in FI are not latching on to any particular pattern which is obvious with where they keep progging HP. All over the north basically run to run. To our north east, then to our north and nw over greendland, hiegh rises over the pole and then over Canada.

One thing is certain though, and thats this stalemate pattern of HP to our east/ north east and LP to the west being shown in all runs every day present timeframe to 168hrs of every run. I cant even get exited now about dreamy deep FI output, I havent seen anything pattern changing coming past 144hrs as of yet. Previously progged HP over the N Pole etc around 144hr didnt get any closer and has since been watered down.

Current pattern to remain for the forseeable imo.

[kold weather]

The positive from the 122z GFS is despite the pattern not being all that cold at the moment on the 12z GFS FI, the pattern is better with the jet being at a better angle then it has been for several months.

[bobbydog]

am i reading it wrong, or do the models want to push the block away in FI? is this the pattern change some have been referring to?

[phil nw.]

the above chart i Compare it to the one for now=very little similarity it seems to me in its shape or the area it was/is in.

I have no idea how this correlates to any way of predicting what the MJO may do even less what that may mean for weather 2-3 weeks down the line.

Anyone?

http://cawcr.gov.au/...Last90days.html

the link above shows how it is now-I hope!

Yes MJO was pretty quiet at this time last November John but here is the latest chart

now in phase 4 with the main core of convection around the Malaysian peninsular and in the next few days forecasted to extend East towards 150E, which is around Phase 5 as suggested by TWS earlier.

Composite for phase 4 is thus

which is at some varience with the current pattern although some pressure build nearby is modelled for the next few days

composite for phase 5 is

which is close to the models ie the readvance of the Atlantic trough later next week.

It`s after that,say beyond day10,where some real changes could occur, if as currently projected, MJO creeps into Phase 6 and beyond.

Composites suggest we could then see low pressure undercutting towards our south with pressure rising further north.

I should say this is all from very tentative early signs for now and we need to monitor the movements of the tropical convection for a few days to get a firmer trend.

We may well see the models toying with some different sypnotics in their later output soon though.

Edited November 3, 2011 by phil n.warks.

[wimblettben]

All the models are presenting nothing but teases in FI and this seems to be every run. I remember us have to clutch at straws for the odd colder Synoptic a couple of years ago where as lately FI seems to be full of colder synoptics every day.

Clearly the models in FI are not latching on to any particular pattern which is obvious with where they keep progging HP. All over the north basically run to run. To our north east, then to our north and nw over greendland, hiegh rises over the pole and then over Canada.

One thing is certain though, and thats this stalemate pattern of HP to our east/ north east and LP to the west being shown in all runs every day present timeframe to 168hrs of every run. I cant even get exited now about dreamy deep FI output, I havent seen anything pattern changing coming past 144hrs as of yet. Previously progged HP over the N Pole etc around 144hr didnt get any closer and has since been watered down.

Current pattern to remain for the forseeable imo.

I wan't this pattern to change even more now as well mate.

These conditions never give us interesting windy or convective weather anymore.

[Snowmad79]

The positive from the 122z GFS is despite the pattern not being all that cold at the moment on the 12z GFS FI, the pattern is better with the jet being at a better angle then it has been for several months.

True but this is another feature repeatadly shown and then dropped in further runs, quite a few of us mentioned this a few weeks ago and nothing much came of it. A more southerly tracking jet with better orientation and a more west to east flow with the HP block to east being decayed. Didn't really pan out like that in the end.

Just as it looks as though it may decay it gets plumped back up again

Yes MJO was pretty quiet at this time last November John but here is the latest chart

now in phase 4 with the main core of convection around the Malaysian peninsular and in the next few days forecasted to extend East towards 150E, which is around Phase 5 as suggested by TWS earlier.

Composite for phase 4 is thus

which is at some varience with the current pattern although some pressure build nearby is modelled for the next few days

composite for phase 5 is

which is close to the models ie the readvance of the Atlantic trough later next week.

It`s after that,say beyond day10,where some real changes could occur, if as currently projected, MJO creeps into Phase 6 and beyond.

Composites suggest we could then see low pressure undercutting towards our south with pressure rising further north.

I should say this is all from very tentative early signs for now and we need to monitor the movements of the tropical convection for a few days to get a firmer trend.

We may well see the models toying with some different sypnotics in their later output soon though.

So much for it remaining stuck around phase 2 heh, which I'm sure some people said would happen and would take a while to change.

Edited November 3, 2011 by Snowmad79

[Cheshire Freeze]

The last several GFS FI runs have certainly been interesting- not so much for any cold they show but for how much potential they exhibit. If the pattern was to play out as per GFS FI then the foundations would be being laid for a cold outbreak towards the latter third of November; which is definately more akin to what I expected this month to bring.

[Frosty.]

The cold blast through NE Europe by the middle of next week is bound to disrupt the placement of the euro high, whether that ultimately favours the uk for a cold snap around mid nov is debatable but there are some interesting signs of change within the next few weeks with low pressure pushing east later next week but a fine and mild spell during the first half of next week. It does then look like turning more unsettled in the north and west after midweek and just like the 6z, it looks generally unsettled towards T+240 hours and further ahead it trends cooler but not as cold as the 6z although a lot of bottled up arctic air will hopefully flood south later in the month depending on where the high goes. This weekend looks very nice across northern britain but unsettled further south with a soggy bonfire night but clear and cool in the north.

[ITSY]

TBH, and maybe its just me, I don't see much change at all. It looks to me like a steady pattern for the next week at least - and all the GFS 12Z showed was nearish to normal November conditions, with no substantial frosts - let alone cold/snow - away from the Highlands of Scotland. The output seems very similar to me to what we were seeing a month ago - with various HP flirtations with Greenland and/or upper Scandi, only for it to be confined to deep FI with alternate suggestions at every run. My bet would be on more of the same of the current average-mild temperatures for at least the next two weeks. The comparison between late FI on the 06Z and the 12Z indicates the folly in searching FI after FI for better runs. Even though, granted, I do exactly that!

[summer blizzard]

Yes MJO was pretty quiet at this time last November John but here is the latest chart

now in phase 4 with the main core of convection around the Malaysian peninsular and in the next few days forecasted to extend East towards 150E, which is around Phase 5 as suggested by TWS earlier.

Composite for phase 4 is thus

which is at some varience with the current pattern although some pressure build nearby is modelled for the next few days

composite for phase 5 is

which is close to the models ie the readvance of the Atlantic trough later next week.

It`s after that,say beyond day10,where some real changes could occur, if as currently projected, MJO creeps into Phase 6 and beyond.

Composites suggest we could then see low pressure undercutting towards our south with pressure rising further north.

I should say this is all from very tentative early signs for now and we need to monitor the movements of the tropical convection for a few days to get a firmer trend.

We may well see the models toying with some different sypnotics in their later output soon though.

Yes MJO was pretty quiet at this time last November John but here is the latest chart

now in phase 4 with the main core of convection around the Malaysian peninsular and in the next few days forecasted to extend East towards 150E, which is around Phase 5 as suggested by TWS earlier.

Composite for phase 4 is thus

which is at some varience with the current pattern although some pressure build nearby is modelled for the next few days

composite for phase 5 is

which is close to the models ie the readvance of the Atlantic trough later next week.

It`s after that,say beyond day10,where some real changes could occur, if as currently projected, MJO creeps into Phase 6 and beyond.

Composites suggest we could then see low pressure undercutting towards our south with pressure rising further north.

I should say this is all from very tentative early signs for now and we need to monitor the movements of the tropical convection for a few days to get a firmer trend.

We may well see the models toying with some different sypnotics in their later output soon though.

I think that the MJO is highly relevant at the moment.

The ECWMF and GEM 0z outputs this morning clearly showed a phase 4 pattern with the mean trough backing west which allowed the ridge to have much more of an influence.

The GFS12z showed a phase 5 pattern with the trough by day 10 close to where it is now, just further south.

The ECWMF12z run should be interesting.

http://www.wetterzentrale.de/pics/MT8_London_ens.png

GFS12z ensembles in pretty good agreement, no chance of a cold shot until the 13th.

[minus 9]

The ecm could'nt come up with a warmer fi if it tried. Oh well plenty of time yet for change. It is only november the 3rd after all.

[Gibby]

Hi folks. here's the evening look at the 12zs from me.

GFS shows low pressure filling near to the UK and relocating over France through the weekend. A very showery 24 hours to come, especially in Central Southern English areas and the Midlands. Over the weekend winds turn NE for a while with everybody feeling rather colder than of late. It would become dry in the North and West with maybe a touch of frost overnight while the South and East sees cloudy and breezy weather with some rain off and on. High pressure drifts SE over Britain early next week giving us all a taste of quiet Autumn weather with near normal daytime temperatures. As the week passes the Atlantic knocks on the door again with Southerly winds and troughs moving in from the West bringing some rain into the West. The rest of the run shows Low pressure taking control with periods of rain or showers at times, heavy in the SW especially with temperatures nearer to the seasonal normal for most of the UK. Some brief drier interludes could occur too at times.

The GFS Ensembles continue to plot above the seasonal normal throughout the run with rain at times after a drier spell between the 7th and the 9th for London. The operational shows a little below the ensemble mean while the control run becomes a mild outlier late in the run.

UKMO tonight shows the same sequence of events as GFS between now and the new week with several dry days to follow early next week when temperatures should be near normal. By midweek a Southerly flow develops again though with little drive from the Atlantic rain bearing fronts should hold off for quite a while, at least in the East.

ECM finally mirrors the UKMO output evolving forward to show another run of very mild air wafting North over the UK later next week. With time Low pressure inches closer to the SW with rain for Western regions late in the run. Many Eastern regions might well stay dry for quite a while and might see a little sunshine at times.

In Summary tonight the models continue to averagely show the mild weather continuing though with a trend from the GFS operational for things to drift nearer the seasonal normal with time. ECM on the other hands keeps the normal temperatures for a shorter time with very mild South winds returning late next week, a situation which looks from it's 144hr chart a trend that UKMO supports. Rainfall would occur most frequently in the West while Eastern areas look like seeing the biggest share of the drier spells.

[Frosty.]

I think it's best to ignore FI and focus on the reliable which looks like becoming generally settled after the poor weekend except for scotland & n.ireland which can look forward to a good weekend for a change with winds dropping light, fairly clear skies by day and night with some ground frost, damp and mild for most of england and wales but then improving next week and staying mild.

[Grimsby Snow Lover]

I think it's best to ignore FI and focus on the reliable which looks like becoming generally settled after the poor weekend except for scotland & n.ireland which can look forward to a good weekend for a change with winds dropping light, fairly clear skies by day and night with some ground frost, damp and mild for most of england and wales but then improving next week and staying mild.

When you say mild do you mean around average for the time of year? The average for around here is around 11/12 degrees c. Going by the GFS that looks like what we are looking at.

[damianslaw]

Very tentative signs from GFS and even hints from ECM if you look at the broader upstream pattern that we may see some stronger pressure rises the our NW by the middle of the month forcing the trough to take a more southerly course in time - but this is a long way off.

Reliable timeframe - trough advecting westwards early next week ushering in a dry spell but probably quite cloudy with risk of frost and fog in clearer breaks. Later next week - trough looks like moving eastwards again to position itself preety much where it was yesterday pumping in more mild southerlies...

We have a bit of a stalemate situation and we require a major change in the upstream pattern to break it... the trigger has to be stronger pressure rises over Greenland caused by lowering heights over NE Canada. I can see the current pattern being very favourable indeed to a slow evolution towards much cooler conditions mid month with a cooler se/e flow as the trough is forced to align itself on a more NW-SE axis as the jet takes a more southerly path. I think the models will pick up on this theme by the weekend - GFS does best when it comes to developments to our NW.

[SMU]

John- wind up merchant? I think you have been at papas ol'moonshine-

I simply stated that a pattern change is in the offering why>? a canadian high doesnt teleconnect very well with a high to our east- it supports low pressure close by or to our east

S

[BLAST FROM THE PAST]

Well I think one should keep focusing now on what FI is pick

ing up on. For me a flow from the N to E quadrant will become apparent late in the month. This would suggest lowering heights to our E/SE.

BFTP

[snowlover2009]

Some very interesting FI charts popping up, even the ECM is not far from showing a high latitude block to our north, this is amazing:

http://hw.nwstatic.co.uk/gfsimages/gfs.20111103/18/384/h500slp.png

Nothing record breaking, but the massive potential for the rest of the month and into December