A Winter 2013/14 outlook.

[phil nw.]

WINTER 2013/14- My View

 

 

I consider this a modest attempt at projecting the likely upper air/surface temperature anomalies in the coming season using only limited but important background trends.

 

I didn't intend to upload a forecast origionally but having got some results from playing around with the NOAA/ESRL reanalysis/composites page-link-

http://www.esrl.noaa...es/printpage.pl

 

i thought they would be of some interest to others so here we go.

 

Method and Data used

I thought i would put together a Winter projection of the basic upper air and surface temperature anomalies based on just 3 background signals.
They are
1.ENSO forecast
2.QBO state
3.October Eurasian Snow extent. (OESE)

I selected the first 2 because they are cyclic and we are able to obtain good longer term trends/forecasts along with a sufficient bank of historical data.
They represent the basic Atmospheric state and the third one just adds a little extra filtering of those years that the first 2 match.

The October Snow Eurasian cover has been shown to create Tropospheric/Stratospheric wave breaking that can weaken and disrupt the Polar Vortex.
Here’s the link to Cohen’s study which has been discussed in the Stratosphere thread.
http://www.nws.noaa....ars/jcohen_0622 11.pdf

 

Right then so going through those 3 items, starting with ENSO.

ENSO(El Nino-Southern Oscillation)
http://en.wikipedia....rn_Oscillation



The current near neutral pattern of Tropical Pacific Sea Temperatures are forecasted to continue through the Winter quarter.
 



Time series data revealed a number of years with neutral starting conditions/forecast since the 1950’s.
http://www.cpc.ncep....ensoyears.shtml


This first result shows the composite Winter 500hPa pattern based just on this one(ENSO)state.

 

 
As expected a rather confused picture there with a lot of years involved.

QBO

The second item I examined was the QBO(Quasi-Bi-Annual Oscillation)
http://en.wikipedia....ial_oscillation

see also Chiono’s first post on the Stratosphere thread for a good explanation.

The coming Winter forecast is for the QBO to revert to a westerly or +ve phase.
http://www.geo.fu-be.../qbo/index.html

I filtered out of those neutral Enso years any – ve QBO phases in those Winters and I then came up with a modified 500hPa Winter pattern

 

 
Fewer years involved now and we are seeing a clearer pattern already.


OESE (October Eurasian Snow Extent)

Finally the state of the Eurasian Snow cover or extent, at the end of October.

This October showed a good +ve anomaly based on historical data.
http://climate.rutge...i_set=1#eurasia
 
 
My final filtering then was to look for those past Octobers prior to the Winter years I had already found and just keep those that recorded a +ve October anomaly.
http://climate.rutge...set=1&ui_sort=0

 

As can be seen from the above I could only find data on this back to the mid-60,’s so I had to drop the earliest 2 years from the remaining set as well as filtering out Octobers where there was no noticeable +ve snow cover anomaly.


After this third and final data search I am left with 2 years only from the from the original ENSO quota, and they are 1979 and 1994.
To be clear these are Winters of 78/9 and 93/4.They were 2 rather different Winters with the earlier 1979 one much more interesting.
Incidentally both had Canadian Warmings but the 78/9 one was in November whereas the later 93/4 one was recorded in December.It may have been the reason why the 93/4 season showed effective vortex disruption somewhat later.


FINAL RESULTS

Ok then these are the composites I got from this basic study.

The overall Winter 500hPa pattern and surface temperature anomalies.

 

Overall those are suggesting an overall  – ve NAO/- ve AO maybe somewhat west based with the UK under low heights with a mean jet around 50N.

Overall temperatures below normal except in the far south west.

This seasonal picture masks a rather different start to Winter though.

Let's look a little closer-

The 3 months
Taking a month by month approach we see a change of pattern as the season progresses.
Here are the height and surface temperature charts for the 3 individual Winter months.



December
 

 

January
 
 

February
 

 

What I deduce from this is that December promises to be a more typical Winter month with a +ve NAO/AO setup and Atlantic Westerly type weather.
Temperatures close to normal in the north but slightly above further south and east where an Euro/Azores high is likely to be quite influential at times.

Looking at the last 2 Winter months’ projections.

A change to a colder pattern is indicated as the Atlantic zonal setup seems to break down.Continental high pressure is replaced by lower heights nearby and around the UK with a weakening vortex to our north.
Cool and cyclonic pattern in January for the UK perhaps with a west based negative NAO pattern and indications of a more southerly tracking jet developing. Possible Northerly outbreak from a Scandinavian trough as the pressure anomalies start to shift away from the zonal theme.

Temperatures easing below normal for the UK and this trend strengthens in February as a more central based –ve AO/-ve NAO pattern is shown-easterly possibilities?

Summary

Winter 2013/14 looks more likely to deliver for cold and snow lovers after the new year with December showing a more typical westerly setup.
I would suggest that the period later in January and into February are looking to be the most promising as that change to a –AO/NAO outlook establishes.

Main points

1. This is a very basic overview from limited- although I believe- relevant data constructing composite 500hPa and temperature anomalies.

2. A fairly normal westerly December.

3. Colder than average after the New Year,especially  later January into February as the changes to our Northern Hemisphere pattern evolve towards the –ve AO/-ve NAO index.

4. Projected monthly CET’s – Dec. 5.5C to 6.0C.  Jan. 3.5 to 4.0C Feb. 2.5 to 3.0C.

5. I would think February is likely to be the driest Winter month based on those height anomalies.


I realise there are many other influences on our weather patterns but i believe those i have presented are a good base to work off.

Good or bad at least it's a learning exercise!

 It will be fascinating to see how the Winter patterns turn out after using just those 3 pieces of a very complicated Atmosphere/Earth jigsaw.

If it’s anywhere close then it should leave cold lovers with some good memories of Winter 2013/14.



 

 

[Don]

Thanks Phil.  I won't be complaining too much if this forecast ends up being close to the mark!  From the forecasts I've seen so far, there does appear to be a growing trend for a normal December with cold potential more likely later in January and February.  Interesting.

[feb1991blizzard]

Well presented and for what my opinions worth, I don't think you will be far out.

[V for Very Cold]

Thanks for the forecast - very comprehensive and interesting reading - certainly won't be disappointed if it comes close.

[mcweather]

Great effort Phil and and a pretty feasible outcome. Thanks for showing your methodology too always enable a forecast to be taken far more seriously.

I wouldn't complain at something along the lines you suggest.

[damianslaw]

A good forecast based on the evidence you have used - and very plausible. We've become used to cold weather pre-new year in recent winters since 08/09, however, your forecast suggests a much more typical winter in that the coldest part of the winter will be the second half.

 

Indeed your December projected pattern isn't far of what GFS is showing for the end of November - yes a long way off. I would think the north in particular would never be too far away from deep cold - Dec 1993 saw a notably cold second half in the north, and Dec 78 I think saw some cold weather in the north.

 

I will be giving my thoughts for what they are worth  sometime during the last week of November.

[joggs]

Thanks for the time n effort Phil.

[Mark Neal.]

A good attempt and good reasoning and analysis of why you think your ideas!

[johnholmes]

blimey phil, and you say you are only a beginner-an awful lot of work in there so many thanks for that.

Like any forecast we have to wait for what the actual data shows.

By the way none of the anomaly charts allow me to view them, I get a note from Net Weather saying I am not allowed?

[Cloud 10]

blimey phil, and you say you are only a beginner-an awful lot of work in there so many thanks for that.

Like any forecast we have to wait for what the actual data shows.

By the way none of the anomaly charts allow me to view them, I get a note from Net Weather saying I am not allowed?

 

Yes,same for me.

 

A very well written and presented forecast which hopefully will be near the mark!

[mike Meehan]

Sounds ok Phil but I have not been able to open up your charts - apparently I am not authorised to see them

[syed2878]

thanks phill i hope your forecast is near the mark.

[Cloud 10]

Hopefully Phil won't mind me re-creating his composites and posting them in larger images.

 

The overall Winter 500hPa pattern and surface temperature anomalies.

 

     

 

 

The 3 months
Taking a month by month approach we see a change of pattern as the season progresses.
Here are the height and surface temperature charts for the 3 individual Winter months.

 

 

December

 

     

 

 

January

 

 

 

February

 

 

[phil nw.]

Thanks Cloud.Yes sorry about the image viewing problem that some of you have experienced.

My fault having copied/pasted stuff from an earlier effort.

 

I have uploaded this pdf file with everything on there.

 

WINTER 2013 final.pdf

 

I Hope this solves the problem.

 

Thanks for the positive feedback so far btw.

Something for everyone if anywhere near the mark.

 

[BornFromTheVoid]

 

Thanks Cloud.Yes sorry about the image viewing problem that some of you have experienced.

My fault having copied/pasted stuff from an earlier effort.

 

I have uploaded this pdf file with everything on there.

 

 

 

I Hope this solves the problem.

 

Thanks for the positive feedback so far btw.

Something for everyone if anywhere near the mark.

 

 

Don't appear to have permission for the PDF either?

 

EDIT: decided pm was better for the question.

Edited November 13, 2013 by BornFromTheVoid

[BornFromTheVoid]

EDIT: Deleted

Edited November 13, 2013 by BornFromTheVoid

[snowhope]

Whether you are right or wrong Phil, thanks for putting together a clear and concise forecast backed up nicely.

I would gladly take your forecast if you are right!

[phil nw.]

 

According the re-analysis page the year is the February in which the Winter ends-i am sure i read that Void-unless i am going mad,lol

Hence the 79 and 94 charts are indeed 78/9 and 93/4 Winter composites.

I don,t see why the pdf wont open -that's strange- i will try adding another file to my earlier post.

Yep, that's true. But for the individual monthly composites, December should be 78 and 93 (not 79 and 94), January 79 and 94, and February 79 and 94, they shouldn't all be same as the winter composite.

By using 79 and 94 for December, you're using the 79/80 and 94/95 winters I think. Confusing!

 

Yes looking at again Void you are right you know.

I can't go back and edit now but it will make December a colder projection than my original one that's for sure.

 

Based on that a correction then.

 

 

December looking very unsettled with signs of a southerly tracking jet and lows headed across the UK,s latitude.

Indications of a weakened vortex over the Canadian side now evident with cold n/ne incursions quite possible north of the jet.This cold affecting the north of the UK especially at times.

It does depend on the placement of the boundary but this looks like a much colder and more interesting month than projected from the first(incorrect)re-analysis.

 

This would revise down the December CET  to a lower 4.5 to 5C rather than the 5.5C to 6C of earlier.

Looking colder for Scotland for sure.

 

 

I am really sorry folks.I got confused on the years when entering them on the analysis.

 

At least it's an even better outlook for cold lovers!

 

Thanks again BFTV.

 

NB.

I will try and get another (revised) pdf file uploaded later.

[phil nw.]

Right hopefully this time everything is correct.

 

Firstly I have attached the 3 months anomaly charts including the revised December analysis.

 

Dec. 

 

Jan. 

 

Feb.

 

Overall Winter(unchanged)

 

 

also 2 doc.types.

 

WINTER 2013 rev..pdf

 

Winter F 2013-14 rev.docx

 

The whole content including revision of text after December correction.

 

I do hope these open for everyone-i think one is an open office doc.I am not great on this aspect of PC work-documents/files etc so please bear with me.

 

Ok i am now off to lie down in a dark room for a few minutes.

 

 

 

[syed2878]

hi phill cant open the pdf ither. Thanks.

[phil nw.]

hi phill cant open the pdf ither. Thanks.

It opens for me-Does the other file open?

Edited November 13, 2013 by phil nw.

[sebastiaan1973]

Thanks Phil. What's your opinion about the small sample size you use, two years?

[BornFromTheVoid]

Right hopefully this time everything is correct.

 

Firstly I have attached the 3 months anomaly charts including the revised December analysis.

 

Dec.  0DuqfcjjCT.pngk6UNKA7AUN.png

 

Jan.  jan ht.pngjan t.png

 

Feb. feb ht.pngfeb t.png

 

Overall Winter(unchanged)

 

combenso-qbo-osc.pngcomb t.png

 

also 2 doc.types.

 

WINTER 2013 rev..pdf

 

Winter F 2013-14 rev.docx

 

The whole content including revision of text after December correction.

 

I do hope these open for everyone-i think one is an open office doc.I am not great on this aspect of PC work-documents/files etc so please bear with me.

 

Ok i am now off to lie down in a dark room for a few minutes.

 

All works fine for me Phil. Cheers for all the work!

Edited November 13, 2013 by BornFromTheVoid

[Cloud 10]

PDF is fine for me also.

 

Loving the December upgrade. 

[phil nw.]

Thanks Phil. What's your opinion about the small sample size you use, two years?

Yes a result of filtering out all the years since the 1960's which didn't show all 3 variables i looked at.

That's how it came out as you can see from the full set of data.

In a way it resulted in a very clear picture as only 2 Winters to study.