Winter 2016/2017: Preliminary Prediction

[Yarmy]

8 minutes ago, iapennell said:

The Ferrel Westerlies are back, now as we draw to the end of October. Much as I suspected they might be and going into November looks set to be wet and windy.

Check out the latest longer-term outlook charts on Wetterzentrale and the BBC Outlook for the month ahead.

[northwestsnow]

3 minutes ago, Yarmy said:

Yes im a bit confused by that post as well, looks to be a lot of dry weather for much of the UK looking at all the data to hand?

 

[iapennell]

Met Office shows south-westerly winds for the next few days, esp over Scotland/North! There is a hint of something drier with some frost next week but southerlies returning later. Nothing to get too excited about as yet, though I am a tiny bit more optimistic about night frosts in November than I was a fortnight ago. I'll not say more than that though!!

[weirpig]

Monday 7 November—Sunday 27 November
Autumn is nearly out of sight!

Pushing this far out in forecasting is always complex and a range of weather solutions will always emerge from the many global computer models that we look at.

The pattern that is emerging looks to be slow moving and high pressure is likely to be close to the UK. This indicates that we are likely to see limited changes in weather on a daily basis and it looks like overall we could see more overnight frosts and fog becoming more extensive. Frontal systems are unlikely to affect the UK while showers are likely close to coastal areas where the sea can still provide enough heating to help produce showers.

There's a lot that can happen until then and remember than we are transitioning from October to November the message is that we are not likely to see anything unusual for this time of year.

 

 

Seems  dry and chilly  with little or no change  at the moment. 

[Scandinavian High.]

1 minute ago, iapennell said:

Met Office shows south-westerly winds for the next few days, esp over Scotland/North! There is a hint of something drier with some frost next week but southerlies returning later. Nothing to get too excited about as yet, though I am a tiny bit more optimistic about night frosts in November than I was a fortnight ago. I'll not say more than that though!!

Met office is going for cooler /colder start November with some wintery showers in the northern parts with frosts  risk increasing ..

[Nick L]

16 minutes ago, iapennell said:

Met Office shows south-westerly winds for the next few days, esp over Scotland/North! There is a hint of something drier with some frost next week but southerlies returning later. Nothing to get too excited about as yet, though I am a tiny bit more optimistic about night frosts in November than I was a fortnight ago. I'll not say more than that though!!

That's not really supporting your comment saying November looks wet and windy though. What draws you to that conclusion?

[Gael_Force]

40 minutes ago, Yarmy said:

I think the expression "farting against thunder" might be approriate here.

49 minutes ago, iapennell said:

Check out the latest longer-term outlook charts on Wetterzentrale and the BBC Outlook for the month ahead. There is high-pressure over Greenland but also pressure looks set to be lower over Scandinavia leading to a spell of north-westerlies but mild southerlies return by the 10th November (Wetterzentrale)

Edited October 26, 2016 by Gael_Force

[johnholmes]

2 hours ago, iapennell said:

Met Office shows south-westerly winds for the next few days, esp over Scotland/North! There is a hint of something drier with some frost next week but southerlies returning later. Nothing to get too excited about as yet, though I am a tiny bit more optimistic about night frosts in November than I was a fortnight ago. I'll not say more than that though!!

Heaven only knows how you get that from their latest text outputs?

their 6-15 day outlook into early November

Outlook for the UK over the next 6-30 days

UK Outlook for Monday 31 Oct 2016 to Wednesday 9 Nov 2016:

For Monday and Tuesday high pressure will stay established across the south, bringing a good deal of dry and quiet weather for many. Some will see patchy mist and fog form overnight though and this may well be slow to clear by day. Temperatures will be mostly above average, but with possibly some cold nights in the south. Meanwhile, the north of the UK is likely to be wetter and windier at times, more so further west. From Wednesday confidence is quite low, although the expectation is for colder weather with more widespread night frosts, and generally northerly or north-westerly winds over the UK. Indications suggest unsettled weather with showers and strong winds at times in the north, and generally drier weather with lighter winds further south.

and their longer forecast out to 24 November

UK Outlook for Thursday 10 Nov 2016 to Thursday 24 Nov 2016:

The outlook for mid November remains uncertain however spells of windier and stormier weather look to be less likely than normally expected at this time of year. Indications suggest that at first northerly or north-westerly winds are likely to predominate over the UK, leading to lower than average temperatures for many and a widespread risk of frosts. The expectation is also for windier more showery conditions in the north, perhaps with snow over some higher ground, and drier more settled weather in the south. Towards the end of the period confidence continues to be low, with the more likely scenario looking to be a continuation of the mainly drier, settled weather, although there is a signal for below average temperatures.

Just where are the south westerly winds Ian please?

I am not going to post the BBC Monthly but it does NOT have anything to say about SW'lys as far as I can see.

I do detest misquotes be it of professional or private folk.

I have not looked at what Wetter suggest but we all know how fickle GFS can be. So apologies if this post offends Ian or anyone else.

Edited October 26, 2016 by johnholmes

[Mapantz]

6 minutes ago, johnholmes said:

Just where are the south westerly winds Ian please?

Well they're certainly not Easterly winds John..

http://www.xcweather.co.uk/

[Nick L]

3 minutes ago, Mapantz said:

Well they're certainly not Easterly winds John..

http://www.xcweather.co.uk/

Come on Mapantz, John was referring to the Met Office forecasts, not current conditions. A little ironic when John was bemoaning misquotes!

Edited October 26, 2016 by Nick L

[jvenge]

1 minute ago, Mapantz said:

Well they're certainly not Easterly winds John..

http://www.xcweather.co.uk/

Indeed, but the text quoted only mentions Northerly or North-Westerly and everything just seems to say calm.

[Mapantz]

1 minute ago, Nick L said:

Come on Mapantz, John was referring to the Met Office forecasts. A little ironic when John was bemoaning misquotes!

But Ian didn't mention anything about any text forecasts..

If you just look at the simple forecasts with graphical icons, it shows winds to the WSW for a few days. If anything, people are misreading Ian's post.

Edited October 26, 2016 by Mapantz

[johnholmes]

7 minutes ago, Mapantz said:

Well they're certainly not Easterly winds John..

http://www.xcweather.co.uk/

that is an actual chart for today. Please read what I quoted, the 6-15 day and 16-30 day outlooks, which to me seemed to fit with the comment from Ian about late October into November. 

Specifically it was this from Ian that caused me, rather unusually, to make my comments

Met Office shows south-westerly winds for the next few days, esp over Scotland/North! There is a hint of something drier with some frost next week but southerlies returning later.

Edited October 26, 2016 by johnholmes

[Mapantz]

5 minutes ago, johnholmes said:

that is an actual chart for today. Please read what I quoted, the 6-15 day and 16-30 day outlooks, which to me seemed to fit with the comment from Ian about late October into November. 

I know it is a chart for today. You quoted Ian saying: Met Office shows south-westerly winds for the next few days

And then you start posting the MetO's text forecast beyond a few days. If you referring to another of his posts, then please quote the correct one.

Seriously, people need to read posts more carefully. 

How is: There is a hint of something drier with some frost next week but southerlies returning later. referring to the MetO's longer range text forecast? That's his own interpretation- I certainly didn't read it as though it was from the MetO's website. Sheesh!

 

Edited October 26, 2016 by Mapantz

[northwestsnow]

The only way i can see ian forecast coming off is if we see High presure sinking back into europe and the jet riding over the top, eventually leading to a more zonal pattern with the vortex cranking up upstream.

Its not the favoured option to my eyes but i wouldnt rule it out, just yet.

[jvenge]

I guess most of Eastern Europe across to Siberia is going to finish comfortably below average for October. Not sure how far the records go back (Only to 1998 for me) to know if any records could be broken.

I saw today that the AO is predicted to stay negative towards the end of November.

[jvenge]

Just to add, might have mixed up the threads there, so mods feel free to move if so.

[Wynn D Woo]

16 minutes ago, northwestsnow said:

The only way i can see ian forecast coming off is if we see High presure sinking back into europe and the jet riding over the top, eventually leading to a more zonal pattern with the vortex cranking up upstream.

Its not the favoured option to my eyes but i wouldnt rule it out, just yet.

The initial forecast was for a rapid deterioration from the 18th October, so I would say it is already a bust, even if we ended up in a mobile westerly regime in the end.

[Matthew.]

Some  thought the general La Niña trend developing through summer would bring a gradual decline in the weather over these months but this turned out quite the opposite and we had a good August/September. Used this example to show the enormous task of predicting the developing high and low pressure system development in conjunction with British weather especially more than a month ahead with so many weather variables. It's only for fun! October has been notable for a easterly direction and who would have thought the Scandi high would be so strong and November looks to continue the cooler than recent months theme with Blocking still a feature, possibly mid-Atlantic giving a Polar feel. I'd be surprised if we have a SW'ly November.

 

Edited October 26, 2016 by Matthew Wilson

[iapennell]

12 hours ago, Nick L said:

That's not really supporting your comment saying November looks wet and windy though. What draws you to that conclusion?

@Nick L, There certainly seems, from a number of models now, to be hints of something drier and colder as we go into November.  However, there are certain fundamentals such as the warmth of waters to the north of Britain, the fact that Eastern Canada and Greenland become very cold as we go into November (strengthening the baroclinic gradient between the North Atlantic and Greenland /NE Canada) and the QBO being in a Westerly phase that lend support to strong Westerlies associated with deep depressions crossing the North Atlantic.  The NE Atlantic has been unusually warm this Autumn and on that basis, anticipating a stronger baroclinic gradient developing across this region going into Winter, is the basis of my prediction for November to be wet and windy, particularly for Scotland and NW England. 

The QBO was in a Westerly Phase (mean wind-speed from the West of over 10 m/s at 30 mb over the Equator) in September and this is a strong indicator of the prevailing winds to come over the North Atlantic into NW Europe a few months down the line. 

However, there has been a good deal more high-pressure over Scandinavia than I anticipated for October 2016 when I made my Autumn prediction, and early November certainly is looking like it could well be drier and colder than I first predicted. I notice that the Arctic sea-ice extent is at a record low for late October and unusually high temperatures have occurred over the European Arctic. If the Arctic is unusually warm over a wide area this would filter through to the upper atmosphere over the Arctic, raising Arctic 500 mb thickness heights and reducing the baroclinic gradient on the periphery which could reduce the intensity of depressions and allow blocking-highs to form over Scandinavia. The rapid increase in Eurasian snow-cover noted elsewhere on this Forum would aid the rapid development of a stronger (and more extensive) Siberian High: It is possible that these developments have aided the persistence of a strong blocking-high (with central pressure at times at 1050 mb) over Scandinavia this month. 

The fact that the ENSO Cycle is moving towards La Nina is also supportive of weaker Westerlies in higher latitudes and this may well have assisted the persistence of high-pressure over Scandinavia. 

An extensively warm Arctic can lead to weaker atmosphere temperature gradients between it and mid-latitudes and that would drive weaker depressions, cause weaker Westerlies and allow blocking-highs to form over higher-latitude continents. However if the Arctic interior still gets very cold whilst sub-arctic waters are several degrees warmer than usual a strong baroclinic zone will still occur, only in higher latitudes than normal. This would prohibit high-latitude blocking-highs. Warmer than usual surface waters warm the air above it, causing it to expand, and that causes lower pressure (other things being equal). 

Another factor opposing the persistence of relatively weak Westerlies that would allow cold dry weather to occur and persist over Britain is the fact that the NE Trade Winds will be strengthening as North Africa, southern Asia and the USA cool and strengthen the subtropical high-pressure belt over them as a result: This adds Westerly AAM to the Northern Hemisphere general circulation at a higher rate and this leads to a need for a correspondingly greater sink for this Westerly AAM elsewhere. As this is likely to become the case soon there would have to be something pretty good to ensure we get cold dry November weather. At present I am far from convinced we have the right sea surface temperatures north of Britain, nor the right wind-direction high above the Equator to ensure we have a blocking-pattern capable of resisting the inevitable increase in Westerly momentum of the upper air that is soon likely to happen. 

 

[iapennell]

13 hours ago, Gael_Force said:

I think the expression "farting against thunder" might be approriate here.

Is that really necessary? 

Just so you know, I have been educated to degree-level in meteorology. Thanks. 

[Gael_Force]

6 hours ago, iapennell said:

Is that really necessary? 

Just so you know, I have been educated to degree-level in meteorology. Thanks. 

That's great.

The comment was about your persistence in referring to Wetterzentrale as being a single model. Most folk on here, with no meteorology education, manage to grasp Wetterzentrale is a site showing many models ..... all showing many different outcomes by day 10-15

[iapennell]

2 hours ago, Gael_Force said:

That's great.

The comment was about your persistence in referring to Wetterzentrale as being a single model. Most folk on here, with no meteorology education, manage to grasp Wetterzentrale is a site showing many models ..... all showing many different outcomes by day 10-15

I get that : The same is true of the forecast pressure -charts on Meteociele, the French site and those produced by the Met Office. Even then, there are differences, because they will use different models and the Met. Office uses it's own very powerful super-computer capable of billions of calculations per second to run it's own predictions. Even then, the UK Met Office will only post predictions based on a mean ensemble of dozens of runs. Even then, as you will know, they still do not always get it right. 

In making predictions beyond a month one can only go by the influence of large-scale parameters that are liable to persist over the course of months ahead, such as sea-surface temperatures over different regions, the Sunspot Cycle, ENSO and the Quasi Biennial Oscillation. Even with their powerful super-computers organisations like the Met Office cannot reliably predict the weather more than a month out and so we have to fall back on how the large-scale parameters influence prevailing weather conditions based on sound meteorological principals. This is what I do when I make seasonal predictions, but I would not say this infallible, because even the large-scale parameters can change in unexpected ways over two or three months (even though they are the most reliable factors to base a seasonal forecast on). A recent example of this is the QBO, which was due to go into it's Easterly Phase this summer,  but something disturbed it earlier this year and so it remains (quite strongly) Westerly. 

My understanding of the fundamentals that drive our weather, and the state of these fundamentals, does not at this moment in time convince me that recent blocking-highs over Scandinavia will feature heavily through this winter, though I am expecting some spells with cold dry and frosty weather due to high-pressure over Europe in January /February. 

I am not oblivious to what the main meteorological outlook sites are showing and do factor them into the start of my forecast period as the Winter draws close. However, one cannot go by them more than a month out. Believe you me, I have got my hopes up in the past when Wetterzentrale has shown cold northerlies bringing hard frosts a fortnight out, only to get my hopes dashed as the time drew near for the hoped-for October cold spell to happen! 

I hope this helps to clarify my stance on the major prediction sites. 

[ALL ABOARD]

3 minutes ago, iapennell said:

when Wetterzentrale has shown cold northerlies

Your still missing the point that people are trying to make .

Wetterzentrale , Meteociel are all websites that provide us with different charts to view, whether this be the GFS, ECM, NAVGEM, GEM etc..

We are merely trying to ascertain what charts on the sites you are viewing to make your assumptions.

NOT THE WEBSITE THE CHART:)

 

[NorthYorksWeather]

Wasn't it Wetterzentrale that correctly forecasted the cold snap in Dec 2010? Or was it Meteociel? Can't remember