Winter 2017-18: Discussion

JCX BXC

nagdefy wrote: »

He's 100% right on the 1740-41 famine. Proportionately many more killed than during the potato famine of the 1840s.

https://en.wikipedia.org/wiki/Irish_Famine_(1740%E2%80%9341)

Also a bug bear of mine is people tend to think there was only one irish famine. Post Cromwell 1660s a very bad one, late 1870s, 1890 in parts of the country to name just a few off the top of my head. Most centuries had a few famines. Well documented in The Annals of the Four Masters etc.

Around the same numbers killed in both, (1million is a fairly accepted figure for both), however far off Mr. Healy (fantasy) Raes 3million figure.

As you say, it was proportionally bigger, as the population was quite low (2.7 million) in the former.

nagdefy

JCX BXC wrote: »

Around the same numbers killed in both, (1million is a fairly accepted figure for both), however far off Mr. Healy (fantasy) Raes 3million figure.

As you say, it was proportionally bigger, as the population was quite low (2.7 million) in the former.

That's it 38% as opposed to 1 million out of 8 million from famine in the 1840s 12.5%, who died from actual starvation. A catastrophe buried by folk memory of the more recent major famine.

Healy Rae had a lot of half truths, 1816 the year without a summer after Tambora eruption etc. He muddled it up and spoke with such colloquial ineloquence that the comment section of online newspapers etc had a field day I'd say he mixed up the figure of the actual population in 1739/40 with the fatalities.

Regardless of the subject of climate change as a whole it's ironic he was denounced totally by know it alls who actually knew nothing on some of the specifics he hit on. The year without a summer, 1740/41 famine, 1870s wet years etc. If ever the saying a wise man will learn from a fool but a fool will never learn from a wise man was more apt!

A lot of people don't realise..still.. how clever the Healy Raes are in pitching to their constituents. The wisest fools in Christendom.

sryanbruen

ENSO is continuing to give me headaches on what it will turn out like for Winter 2017/18. About a week ago, it was clearly showing La Nina signature but that signature has now disappeared within the space of a week.

The Atlantic is generally warm again so that is not doing us any favours BUT at least it's better than it being cold with the infamous cold blob that we had during the previous few Winters, most notably in Winter 2015/16.

The QBO is clearly in an easterly phase. For anybody who doesn't know, the QBO (Quasi-Biennial Oscillation) is an index that tells you the state of the westerlies. If the QBO is in a westerly phase, it means that the westerlies are intensified through the Atlantic. But if the QBO is in an easterly phase, it means that the westerlies are weakened through the Atlantic. Winter 2009/10 had an easterly QBO, Winter 1946/47 had an easterly QBO and Winter 1962/63 had an easterly QBO - just three notable examples. Going by historical evidence, an easterly QBO is good for a Winter as it weakens the westerlies and makes it easier for blocking to take place therefore. However, like any other factor or methodology in forecasting our weather, it is not any guarantee and is to be treated with equal attention as any other factor. For example, Winter 1990/91 (which had a notably cold February - less so for Ireland though as it was in the UK) had a westerly QBO but Winter 1997/98 (which had a very strong El Nino and the warmest February on record) had an easterly QBO.

One of the reasons why we were so unlucky in Winter 2016/17 for a cold Winter was the QBO. It was meant to be in an easterly phrase but something happened in the atmosphere to cause the westerlies to become stronger and destroy the chances of the easterly QBO coming for 2016/17. Instead, we had a westerly QBO. Here's one example during 2016/17 where we could have been in a bitter cold spell but due to the westerly QBO, it was very temporary and not all that cold (10 February 2017):



The westerlies outdid the Scandinavian block a few days later and we were firmly in an Atlantic onslaught. If we get the blocking going, at least there won't be any intensified westerlies this time to make it only very temporary.

Solar activity is at low levels but we are still not at solar minimum yet which should be achieved by 2019 or 2020. The best chances for cold winters using solar activity methodology is just after solar minimum like 1995/96, 1996/97, 2009/10 or 2010/11 for recent examples.

The Siberian high is very strong right now and is creating quite a big expansion of snow cover across the Russian Federation. A strong Siberian high can be our best friend or our worst enemy. It can be our best friend as it aligns with a block from Greenland or Scandinavia to create very stubborn northern blocking and in turn give us very cold weather. Or it can be our worst enemy where it goes over to Canada and gives them very cold conditions which in turn blow up the jet stream and give us very stormy conditions. This was the case in 2013/14 for example. 2013 had a quick expansion of snow cover across Russia but the Siberian high went over to Canada and the USA to bring them a very cold, snowy Winter which in turn led to us achieving our wettest and stormiest Winter on record. We are on a par with 2013's Siberian snow cover, so it could go two ways.

Frankly, despite the QBO, I am not thinking highly of this Winter. My early thoughts was for the best chance of any cold weather to be taking place in December 2017 but then become very stormy in January and February.

Floki

Sryanbruen you're a national treasure to have on here.

Between your posts in this thread and the ENSO thread you're brilliant.

Not sure if this is based on statistics but I used to look at the met eireann monthly summaries and try and compare it to the ENSO conditions at the time from the NOAA records and it looks to me like all the people living all along the river Shannon should be delighted now with the change in ENSO for now anyway. Donegal looks like it will still get hit though. No change there.

But just Sryan keep up the eloquent and informative posts.

(ps. Don't get a big head. ):D

nacho libre

sryanbruen wrote: »

Frankly, despite the QBO, I am not thinking highly of this Winter. My early thoughts was for the best chance of any cold weather to be taking place in December 2017 but then become very stormy in January and February.

Why is that? In the winters of 2009 and 2010 was the QBO in an easterly phase. I recall reading on netweather that in rare circumstances even with the nao in a positive state and with a strong polar vortex, we can still manage to get a cold spell. One thing about that cold blob of water in the Atlantic you mentioned, it had the effect in recent winters of creating heavy snow showers in the west of Ireland that normally would have fallen as rain.
I think we will see some snow this winter, but we are overdue an event that leads to a decent covering. I long to see a weather map with a polar low heading in our directions.

sryanbruen

Floki wrote: »

Sryanbruen you're a national treasure to have on here.

Between your posts in this thread and the ENSO thread you're brilliant.

Not sure if this is based on statistics but I used to look at the met eireann monthly summaries and try and compare it to the ENSO conditions at the time from the NOAA records and it looks to me like all the people living all along the river Shannon should be delighted now with the change in ENSO for now anyway. Donegal looks like it will still get hit though. No change there.

But just Sryan keep up the eloquent and informative posts.

(ps. Don't get a big head. ):D

:pac: thanks very much.

If you'd like to know about historical Irish weather whether it's IMTs (Irish Mean Temperatures), summaries etc, please check out the Irish Weather Statistics thread: http://www.boards.ie/vbulletin/showthread.php?t=2057714322&page=10

Recently, I posted part 1 to my Winter 1946/47 70th anniversary article. In the thread, you will also find tables by me which were analysed from online data into one full table divided into two (one from 1946/47 to 1983/84 and the other from 1984/85 to 2016/17). These tables show you what the Winter was like in terms of the methodology we use whether it's the AO, NAO, NAO in May, SSW, OPI, PDO etc. I also added in the UKMTs and CETs. When I calculate the IMTs back to 1946/47, I will update the tables to include the IMTs for each of the Winters. These tables were designed by me to be a simple source to making Winter forecasts based on historical weather instead of having to look up online on multiple sites for data. I can assure you that all the information on the tables is correct and none of it is false - although the OPI for 2015 and 2016 is estimated by me as there is no data of the OPI for those years after it was left to death in early 2015. These tables had been checked a lot of times before I released them to this forum and my weather enthusiast friends.

Another huge weather enthusiast who is a friend of mine makes his own analysis based on my tables - like a table including only cold Winters, such as the one at the bottom of this post:

http://www.boards.ie/vbulletin/showpost.php?p=104086045&postcount=114

sryanbruen

nacho libre wrote: »

Why is that? In the winters of 2009 and 2010 was the QBO in an easterly phase. I recall reading on netweather that in rare circumstances even with the nao in a positive state and with a strong polar vortex, we can still manage to get a cold spell. One thing about that cold blob of water in the Atlantic you mentioned, it had the effect in recent winters of creating heavy snow showers in the west of Ireland that normally would have fallen as rain.
I think we will see some snow this winter, but we are overdue an event that leads to a decent covering. I long to see a weather map with a polar low heading in our directions.

We are not in the favourable phase of the solar cycle for one along with other factors such as the Siberian High possibly bringing a very stormy Winter if it ends up on the wrong side of the Northern Hemisphere.

Winter 2009/10 did have an easterly QBO but 2010/11 had a westerly QBO.

Yes, I just gave one example as such above, 1990/91. That had a positive AO, positive NAO, westerly QBO, high solar activity and an OPI that was on the positive side of neutral - all factors that would not be favourable for a cold Winter. Yet in the end it was a cold Winter and had a very snowy spell for the UK. They had to wait until February 2009 to find a spell as close to being snowy or cold as February 1991's one. Winter 2008/09 is another interesting Winter because it had a positive AO, positive NAO and a westerly QBO like 1990/91.

But anyway, you can see all this for yourself in the link I just mentioned above to Floki.

M.T. Cranium

It would take a brave person to predict cold weather in the first half of this winter given the highly zonal flow and the large dome of high pressure over south-central Europe.

So I will be timid and predict cold weather in the second half of the winter, at least for some part of it, as various indicators are no worse than variable, not all mild all the time -- details to follow in about a week or two, as I do my annual number crunching. Analogue sets show a tendency to January cold and close to normal in other months.

sryanbruen

M.T. Cranium wrote: »

It would take a brave person to predict cold weather in the first half of this winter given the highly zonal flow and the large dome of high pressure over south-central Europe.

So I will be timid and predict cold weather in the second half of the winter, at least for some part of it, as various indicators are no worse than variable, not all mild all the time -- details to follow in about a week or two, as I do my annual number crunching. Analogue sets show a tendency to January cold and close to normal in other months.

What analogue is this out of curiosity? What's it based off?

The closest the models have been hinting at something cold for Winter 2017/18 has been December 2017, especially the CFSv2 though even with that, nothing spectacular.

The only thing I take from Autumn for Winter forecasting personally is the OPI, or pattern setup in October though even that I take with a pinch of salt as much as everything else. If my estimates are right, the OPI for this October should be on the positive side of neutral so far though very close to bang on neutral. This is normally a bad sign for Winter but since 2013, there's been three fails of the OPI in helping predict the Winter, 2013, 2014 and 2016 which all had negative OPIs with 2014 being the second most negative since 1970 with only 2009 being more negative.

You're literally going for the opposite of what 2016/17 was expected to be - the early part of the Winter cold and the latter half mild when in the end, both halves were mild.

hatrickpatrick

Bumping this, now that the excitement of Ophelia is fading and the forum is returning to a more usual level of traffic.

How soon will we have a firm of idea of how the NAO will set up for the winter? Still looks to be trending negative:

sryanbruen

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

Donegal Storm

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

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

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

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

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

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

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

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

George Sunsnow

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

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

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

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

spookwoman

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

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

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

sryanbruen

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

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

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

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.