Winter 2017-18: Discussion

sryanbruen · 20-10-2017 7:28am

Yes, at the same time, the GFS ensembles are forecasting the AO to go very positive.

Donegal Storm · 20-10-2017 9:32pm

As mentioned recently, the NAO is just an output of the most recent model runs based on the difference in north Atlantic pressure, from what I've seen it's not really an indicator of anything more than that.

Forecast is for a more meridional flow next week with low pressure sinking to the Azores, hence the negative NAO

sryanbruen · 20-10-2017 9:40pm

Donegal Storm wrote: »

As mentioned recently, the NAO is just an output of the most recent model runs based on the difference in north Atlantic pressure, from what I've seen it's not really an indicator of anything more than that.

Forecast is for a more meridional flow next week with low pressure sinking to the Azores, hence the negative NAO

The NAO is an index that tells you the state of the atmosphere over the North Atlantic from Greenland to the Azores. When high pressure is over the Azores, it tells you the NAO is strengthened to be positive and normally would mean low pressure is over Greenland/Iceland but sometimes you can have high pressure at both which leads to them canceling each other out (depending on how stubborn the anticyclones are) and having a neutral NAO. My friend Gavin Partridge of GavsWeatherVids predicted a neutral NAO for Winter 2017/18. There has only been one neutral NAO Winter in the last 60 years, Winter 1979/80.

It's not necessarily an "indicator" but it is a methodology we use in predicting weather, especially for the Winter. 2009/10 had the most negative NAO index on record. Most cold Winters tend to have a negative NAO as you can see from my table below in the first column:

But, saying all that, it is as important as any other methodology in predicting weather. We must treat it equally as much as ENSO, AO, PDO, SSW events, QBO etc.

Donegal Storm · 20-10-2017 9:56pm

Yeah my point is just checking the latest NAO trend isn't an indicator, there seems to be a mentality on here that a negative trending NAO=cold weather for us. Simply looking at the latest model runs will tell you a lot more about the forecast than what the NAO index is showing.

The negative NAO forecast for this coming week is because of a meridional flow where there's high pressure over the eastern US and over western Europe with low pressure in between over the Atlantic, nothing more than that. In the right setup it can result in a blocked Atlantic and cold weather for us but from the reading I've done it's more a product of conditions than a driver

sryanbruen · 20-10-2017 9:58pm

Donegal Storm wrote: »

Yeah my point is just checking the latest NAO trend isn't an indicator, there seems to be a mentality on here that a negative trending NAO=cold weather for us. Simply looking at the latest model runs will tell you a lot more about the forecast than what the NAO index is showing.

The negative NAO forecast for this coming week is because of a meridional flow where there's high pressure over the eastern US and over western Europe with low pressure in between over the Atlantic, nothing more than that. In the right setup it can result in a blocked Atlantic and cold weather for us but from the reading I've done it's more a product of conditions than a driver

No index is a driver, they can only show what's happening right now (though as a number instead of a map showing the setup), not tell you what is going to happen. So yes.

sryanbruen · 20-10-2017 10:04pm

This forecaster seems awfully confident for his Winter 2017/18 forecast :pac:.

http://www.weatherwithouttechnology.co.uk/download/ADVANCE%20PREDICTIONS%20WINTER%202017%20to%202018.pdf

Donegal Storm · 20-10-2017 10:19pm

sryanbruen wrote: »

No index is a driver, they can only show what's happening right now (though as a number instead of a map showing the setup), not tell you what is going to happen. So yes.

Yeah but some indices like the AMO, QBO etc have patterns and clearer effects and are more predictable medium term so they're more indicative. NAO is only really reliable week to week so a simple look at SLP charts will tell you a lot more than the index shows.

I'd say it's a lot more useful as a reanalysis tool than a forecasting tool

0byme75341jo28 · 21-10-2017 12:36am

I've just a quick question there..

Something I've always noticed looking at the rainfall radar is the slightly SE/NW "line" of rain over county Cork going up into Tipp or Limerick (not sure which) and down into the coast. What causes that? I doubt it's actually rain, is it interference from some other source?

carltonleon · 23-10-2017 1:06pm

Surely it must be time for the Indo or Daily Mail to have a 'Snowmegeddon' forecast !!!!! Must be

George Sunsnow · 23-10-2017 1:28pm

Allan Crooked Laser wrote: »

I've just a quick question there..

Something I've always noticed looking at the rainfall radar is the slightly SE/NW "line" of rain over county Cork going up into Tipp or Limerick (not sure which) and down into the coast. What causes that? I doubt it's actually rain, is it interference from some other source?

Yup radio interference or false echoes off mountains

kstand · 23-10-2017 3:23pm

carltonleon wrote: »

Surely it must be time for the Indo or Daily Mail to have a 'Snowmegeddon' forecast !!!!! Must be

http://www.express.co.uk/news/weather/868795/UK-winter-weather-forecast-2017-snow-long-range-weather-forecast-Met-Office-BBC-weather
Early even for Nathan Rao!

JCX BXC · 23-10-2017 4:13pm

I particularly love this line "Despite last few years initially showing signs of following suit, Britain has managed to dodge a severe cold snap."

Basically, "we've been taking sh*t for years, but some of you are stupid enough to believe us this year"

nagdefy · 23-10-2017 5:31pm

The usual suspects.. James Madden of Inexacta Weather, Piers Corbyn etc.

spookwoman · 23-10-2017 9:07pm

nagdefy wrote: »

The usual suspects.. James Madden of Inexacta Weather, Piers Corbyn etc.

Yep be careful with Corbyn he has a thing for swiping peoples pictures and posting them on his twitter account along with the cost to his weather subscription service. Don't know how many times and by how many he's been reported to twitter over it

M.T. Cranium · 23-10-2017 9:44pm

I have a forecast more or less prepared for delivery on Wed 25th, and let's just say it won't be front page news for any tabloids.

MidMan25 · 23-10-2017 9:48pm

No offence intended, but being a coldie, i'm glad your last one was way off :pac:

sryanbruen · 23-10-2017 9:49pm

MidMan25 wrote: »

No offence intended, but being a coldie, i'm glad your last one was way off :pac:

Whatcha mean? Am I missing something here?

:)

JCX BXC · 23-10-2017 9:56pm

sryanbruen wrote: »

Whatcha mean? Am I missing something here? :)

I think they mean that last year's suggestion of snow didn't come off, and they're glad as they're a cold person.

There's no need to be so shocked at everything Syran!

sryanbruen · 23-10-2017 10:00pm

JCX BXC wrote: »

I think they mean that last year's suggestion of snow didn't come off, and they're glad as they're a cold person.

There's no need to be so shocked at everything Syran!

I was not paying attention to his forecast last Winter, probably due to the fact that I was unable to post then, so I really didn't know.

I don't see what you are getting at with that because I didn't know.

I personally saw a good chance at getting something colder in 2016/17 but I have learned so much in the past year - and will do so again in the next year (I'm not confident whatsoever for this Winter). The problem that made last year so unnecessarily complicated to forecast was the unique QBO. We may not have a unique QBO this year but we still have an ENSO event that's so late going on and a very warm Norwegian/Greenland/Barents Sea.

JCX BXC · 23-10-2017 10:03pm

M.T, could you do is a favour and give us a little hint in the morning? We're not particularly great at suspense here in the weather forum!

Hopefully I may finally be blessed with a snow flurry here in West Clare, but one learns that it's quite low of a chance.

MidMan25 · 23-10-2017 10:06pm

JCX BXC wrote: »

I think they mean that last year's suggestion of snow didn't come off, and they're glad as they're a cold person.

There's no need to be so shocked at everything Syran!

Yep, last year's prediction:

"Winter 2016-17 Outlook: I am expecting a rather different outcome from last winter, and something a little similar to 2010-2011 which started out very cold and snowy, then turned much milder. This winter, I am predicting rather cold weather to start, from late November through much of December, and the opportunity for some significant snowfalls. It probably won't be as intense as the cold or snow of late 2010, let's say on the order of two degrees below average and 5-15 cm snowfalls possible in the period (recall that Dec 2010 produced some 30-40 cm falls in Leinster). As usual, this snowfall would be more likely in the eastern half of the country and in some parts of the northwest. Then I expect a much milder pattern to develop in January peaking towards the end of the month with very mild weather. February and March look fairly average in my research output"

December was warmer and drier than average

January was warmer and drier than average (In fairness MT called January right)

February was warmer and drier than average

March was warmer and wetter than average

sryanbruen · 23-10-2017 10:16pm

MidMan25 wrote: »

Yep, last year's prediction:

"Winter 2016-17 Outlook: I am expecting a rather different outcome from last winter, and something a little similar to 2010-2011 which started out very cold and snowy, then turned much milder. This winter, I am predicting rather cold weather to start, from late November through much of December, and the opportunity for some significant snowfalls. It probably won't be as intense as the cold or snow of late 2010, let's say on the order of two degrees below average and 5-15 cm snowfalls possible in the period (recall that Dec 2010 produced some 30-40 cm falls in Leinster). As usual, this snowfall would be more likely in the eastern half of the country and in some parts of the northwest. Then I expect a much milder pattern to develop in January peaking towards the end of the month with very mild weather. February and March look fairly average in my research output"

December was warmer and drier than average

January was warmer and drier than average (In fairness MT called January right)

February was warmer and drier than average

March was warmer and wetter than average

Whilst the closest to his prediction being right was January, I would also like to point out that he said for January to be the mildest of the three when in actual fact, it was the coolest out of the three. Central England was actually -0.1c below its January average if you use the 1981-2010 average. These are the IMTs for each month last Winter and their anomalies:

December: 6.7c (+1.1c)
January: 6.1c (+0.6c)
February: 6.4c (+1.1c)

IMTs calculated from Met Éireann and UKMO's historical data

However, I have sympathy for him for his forecast because I was in the same situation as him. I predicted a cold Winter given how the pattern was looking at the time when I released it. The one gripe that gave every one of us forecasters headaches last year was the QBO as I just mentioned. The QBO was unique for 2016/17. There was never a year going back to 1950 where the QBO matched with 2016/17. The QBO followed its normal system in 2015/16 when it was a westerly QBO. You would expect it to go easterly for 2016/17 and for a time around April-May 2016, it looked like it would. As you know already, I've explained what the QBO is and how it works along with how easterly QBOs help increase the chances of a cold Winter. But by the Summer and the latter half of the year, the westerlies then outdid the chances of an easterly QBO happening and the westerly QBO took over again for 2016/17. Like I said, never once back to 1950 has an event like that occurred.

MidMan25 · 23-10-2017 10:30pm

Not trying to put anyone down etc, just calling a spade a spade.

Your post aludes to how difficult it can be to even predict roughly how a month will turn out.

beefburrito · 24-10-2017 9:12am

Soon enough I'll open up the same book I've read a few times over the last few years.

"Ireland's Arctic Siege" by Kevin Kearns it's a great crackling fire side read coming into the winter months....a few pages an evening will get the snow bunnies excited...

sryanbruen · 24-10-2017 9:47am

beefburrito wrote: »

Soon enough I'll open up the same book I've read a few times over the last few years.

"Ireland's Arctic Siege" by Kevin Kearns it's a great crackling fire side read coming into the winter months....a few pages an evening will get the snow bunnies excited...

So you would recommend it? I’ve been thinking of getting it.

sideswipe · 24-10-2017 9:50am

Can anybody tell me when the current alert system was brought in to give the yellow, orange and red designations?

George Sunsnow · 24-10-2017 9:54am

The alert system isn’t more than a decade old I think

As for snow-coastal low ground Ireland where most people live is probably one of the most hostile environments usually for a snow flake in the world

beefburrito · 24-10-2017 10:53am

sryanbruen wrote: »

So you would recommend it? I’ve been thinking of getting it.

It's a must buy,it always comes out around this time of year.
It's best read on a damp cold evening.....
I bought it a few years ago...
I'm sure there's still copies left.

pistolpetes11 · 24-10-2017 11:51am

beefburrito wrote: »

Soon enough I'll open up the same book I've read a few times over the last few years.

"Ireland's Arctic Siege" by Kevin Kearns it's a great crackling fire side read coming into the winter months....a few pages an evening will get the snow bunnies excited...

Would be great to digest it with some of the white gold pouring down outside :cool:

beefburrito · 24-10-2017 12:11pm

pistolpetes11 wrote: »

Would be great to digest it with some of the white gold pouring down outside :cool:

One eye on the page another on the lamppost outside ðŸ˜

Tabnabs · 24-10-2017 12:14pm

Lucky hill tops

https://twitter.com/wxweb/status/922766504587866112

weisses · 24-10-2017 12:14pm

M.T. Cranium wrote: »

I have a forecast more or less prepared for delivery on Wed 25th, and let's just say it won't be front page news for any tabloids.

Would be nice If you can reflect on previous long term predections

Were you happy with your summer predictions ?

Tabnabs · 24-10-2017 12:18pm

Telemark, Norway this morning

https://twitter.com/Meteorologene/status/922781715562749952

BoatMad · 24-10-2017 12:49pm

Nice mild non descript winter just like last year please. Easy on the bones and the bills

sryanbruen · 24-10-2017 1:17pm

beefburrito wrote: »

It's a must buy,it always comes out around this time of year.
It's best read on a damp cold evening.....
I bought it a few years ago...
I'm sure there's still copies left.

Have you read Deluge: Ireland’s Weather Disasters 2009-10?

PokeHerKing · 24-10-2017 7:43pm

BoatMad wrote:

Nice mild non descript winter just like last year please. Easy on the bones and the bills

Where's the fun in that!!

sryanbruen · 24-10-2017 7:49pm

PokeHerKing wrote: »

Where's the fun in that!!

Seeing people complain despite it doing absolutely no harm

.

highdef · 24-10-2017 11:06pm

sryanbruen wrote: »

Seeing people complain despite it doing absolutely no harm .

Says your man who obviously pays nothing towards heating bills!

sryanbruen · 25-10-2017 7:26am

highdef wrote: »

Says your man who obviously pays nothing towards heating bills!

I don't get what that has to do with Winter 2016/17.

P.S. I do pay towards heating bills sometimes using my allowance if I have no choice but to and also I haven't used the heater myself in nearly 2 hours.

JCX BXC · 25-10-2017 6:58pm

M.T. Cranium wrote: »

I have a forecast more or less prepared for delivery on Wed 25th, and let's just say it won't be front page news for any tabloids.

Our Wednesday or your Wednesday MT?

Pappacharlie · 30-10-2017 9:23am

Morning MT

Could you post a link to your long range forecast at your convenience.

Thanks.

JCX BXC · 30-10-2017 9:52am

Pappacharlie wrote: »

Morning MT

Could you post a link to your long range forecast at your convenience.

Thanks.

Has not been issued yet.

h7nlrp2v0g5u48 · 30-10-2017 12:42pm

JCX BXC wrote: »

Has not been issued yet.

Looking forward to MT's long range forecast. He might have some surprises for us this Winter.

snaps · 30-10-2017 1:24pm

So my winter update from southern Poland. Just sneaked our first heavy snowfall of the season into October. Late this year by a couple of weeks.
Last photo is at about 1200m ASL in our village.
The rest of the photos are taken from social media (So not mine) from around Zakopane.

John mac · 30-10-2017 1:26pm

only seeing one pic though , the other 3 are only showing 1 pixel ..

snowstorm445 · 30-10-2017 1:28pm

http://waterfordwhispersnews.com/2017/10/30/bull****-warning-issued-as-annual-worst-winter-in-50-years-articles-emerge/

JCX BXC · 30-10-2017 2:25pm

snowstorm445 wrote: »

http://waterfordwhispersnews.com/2017/10/30/bull****-warning-issued-as-annual-worst-winter-in-50-years-articles-emerge/

Was just about to post that!

Strange occurrence when Waterford Whispers are more accurate than the tabloidy weather news.

Sadly, due to boards filter on the word sh!t, the article won't load, however look up Waterford Whispers on Facebook and you should find the article.

lapua20grain · 30-10-2017 3:40pm

JCX BXC wrote: »

Was just about to post that!

Strange occurrence when Waterford Whispers are more accurate than the tabloidy weather news.

Sadly, due to boards filter on the word sh!t, the article won't load, however look up Waterford Whispers on Facebook and you should find the article.

Just read it, brilliant as always

esposito · 30-10-2017 6:37pm

natashaob6 wrote: »

Looking forward to MT's long range forecast. He might have some surprises for us this Winter.

He might. But will they come true

h7nlrp2v0g5u48 · 30-10-2017 8:22pm

John mac wrote: »

only seeing one pic though , the other 3 are only showing 1 pixel ..

I can't see anything either when I click on each one.

Winter 2017-18: Discussion

Comments