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Winter 2017-18: Discussion
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Stratosphere charts updated to the 21st February. Spike up at 10hPa, spike down at 30hPa.
Photography site - https://www.sryanbruenphoto.com/
Weather photo portfolio - https://sryanbruen.myportfolio.com/weather-1
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Stratosphere charts updated to the 22nd February. Spike down at 30hPa, flat lined at 10hPa.
According to some people, I've heard the effects of the Canadian Warming have not taken place in the troposphere or are expected to do with this cold event, they're thinking this is all to do with last week's major Sudden Stratospheric Warming. This might explain the downwards trend in the zonal wind speeds towards the middle of March after a brief recovery around the 8th-14th. This proves my theory on cold extending into April with brief moderations from time to time during March especially through that recovery of the zonal winds (though still below average speeds). The Atlantic will have a really tough time!
Photography site - https://www.sryanbruenphoto.com/
Weather photo portfolio - https://sryanbruen.myportfolio.com/weather-1
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sryanbruen wrote: »Stratosphere charts updated to the 22nd February. Spike down at 30hPa, flat lined at 10hPa.
According to some people, I've heard the effects of the Canadian Warming have not taken place in the troposphere or are expected to do with this cold event, they're thinking this is all to do with last week's major Sudden Stratospheric Warming. This might explain the downwards trend in the zonal wind speeds towards the middle of March after a brief recovery around the 8th-14th. This proves my theory on cold extending into April with brief moderations from time to time during March especially through that recovery of the zonal winds (though still below average speeds). The Atlantic will have a really tough time!
Yeah. I think if the Atlantic does get back in it will only be temporary. One professional forecaster(Nick F) over on netweather was saying the Alantic could be in a very weak State till nearly May
Also one or two of the start experts over on netweather were saying this event might act as the final warming of the vortex. Not sure about that, but I can't see the Vortex renewing to the state it was before the ssw anytime soon!0 -
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Would this not lead to a good summer?
Not exactly. People love to say that a great April means a poor Summer and the opposite. I have said similar things before so I can't pretend I have not - for example, I hypothetically spoke in here that I'd rather a cold Spring and a warm, great Summer than the other way round. Nature does not work like that. There's years where the whole year was cold and awful - 1879 being an example. Every month from November 1878 to January 1880 was colder than average using the respective dataset at the time (it was something like 1841-1870 average though I forget) and against the 1981-2010 average, all months stay the same besides their anomaly figures but are still all below average.
As there's no Spring thread, I will post these here.
This reanalysis is of Mays in years ending in "8".
Westerly based negative NAO, southerly tracking jet stream, trough over top of us = Awful!
Remember that you'll always have some exceptions in these reanalysis charts. May 1998 and 2008 are the obvious odd ones out because they were both very warm - May 2008 was the warmest May on record for the IMT and was very sunny so it's not all doom and gloom. Unfortunately, the majority of the Mays in the package are horrible.
This reanalysis is of Summers in years ending in "8".
Severe northern blocking over Greenland, very deep trough over top of us.
That's possibly the worst chart you could get for Summer. Very wet, very cool, very dull! Yuck. The last "good" Summer in a year ending in "8" was way back in 1868. Remember that these very poor Summers are preceded by poor Mays (mostly) as you can see from the above reanalysis.
Here's some more light of hope but is not an accurate analogue because each May is quite different here. This is a reanalysis chart of the Summers following "poor Mays" (in my opinion) since 1990. For a May to be poor for me, it has to be very wet, very wet and cold, wet and cold, wet and dull, or just very cold.
This is a much better chart as it shows a ridge over Scandinavia. This in Summer can bring very hot conditions because Europe is far hotter than it is in the Winter where easterlies bring extremely cold conditions to us. With the trough out to the west, it would suggest a lot of southerlies too and perhaps some spanish plumes. There is quite a variety of Summers in there though, some very cool and wet like 2015 but others are brilliantly hot and sunny like 1995 or 2006.
Photography site - https://www.sryanbruenphoto.com/
Weather photo portfolio - https://sryanbruen.myportfolio.com/weather-1
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Spanish Eyes had asked if there's any similarities with the pattern now to 2010. By 2010, I take it that you were referring to the end of November and the December to remember?
In terms of the science or methodology that I use to make my forecasts, there aren't much similarities at all.
Let me go over what made this period what it was.
Solar activity. Solar Cycle 24 (2008 to present) had began in December 2008 which meant solar activity was at its lowest in December 2008. With solar activity, there's two different phenomena, one is the solar minimum where solar activity is at its lowest and you'll get long periods of spotless days. The other is solar maximum where you'll rarely ever see a spotless day and in fact, solar activity at its maximum point for the solar cycle. Each solar cycle is different in strength, duration etc but the duration is normally around 11-12 years. If you don't know what sunspots are, they're basically dark spots on the sun which stand out because they're very different looking to the sun's appearance. Can you make out the sunspots here on this image of the sun for example? You sure can, it's those small black or dark spots.
Historically, the coldest of Winters are just before, during or after solar minimum. These include 1946-47, 1961-62, 1962-63, 1963-64, 1976-77, 1977-78, 1978-79, 1984-85, 1985-86, 1986-87, 1995-96, 1996-97, 2008-09, 2009-10, 2010-11.
Why do these occur specifically around these parts of the solar cycle? Historically, northern blocking over Greenland, Scandinavia etc tend to be more frequent and more stubborn during these years. We are at the same part of the solar cycle as 2010 was here in 2018 but the main difference is that 2010 was after solar minimum in December 2008 and 2018 here is going into solar minimum by the end of the year or in 2019. If we were to base the solar activity right now on a similar season, it would be Winter 2007-08 which had a few teasers for what was to come in the three following Winters (such as the December anticyclonic spell, January 2008 heavy snow and brief easterly, February 2008 anticyclonic spell, March and April snow showers) and I feel Winter 2017-18 is a teaser of what's to come in the next few Winters from 2018-19 to 2020-21 or even after. Solar cycle 25 is expected to be the weakest solar cycle since the Dalton Minimum and perhaps us going into a mini Ice Age as some people say which will increase the chances of cold Winters historically - Winters during the Maunder and Dalton Minimums were brutally cold though obviously there were mild Winters too. With this in mind, I feel years like 2010 may be a bit more frequent and perhaps more severe, 2018 might become one of those years
. 2018 is set to be the most spotless year on the sun since 2009. 2009 was the most spotless year in more than a century to emphasise the significance of these expectations.
A sensible thing to do in model watching is to look for little teasers that could be precursors forward for something colder whether these teasers are northern blocking, stratosphere warming up, strong Siberian High etc. Look at this example. This is what the GFS 12z on November 16 2010 was showing for November 27 2010 (11 days away at this time so obviously not going to be very accurate). The chart shows the Atlantic in control for us but we're on the knife edge of a bitter cold spell and we got the cold in the end. The teaser here is that blocking over Greenland. That was here throughout 2010 pretty much, there was not a single month that year with positive NAO.
See the 2010 reanalysis here for how persistent and stubborn the Greenland blocking was:
I posted this example from last Saturday's GFS 06z for Thursday 22nd of me highlighting the teasers for this easterly:
2010 had the Iceland volcano eruption which in my opinion was a huge precursor to December 2010. As I have been saying though, I have been carrying out a research project since October 2017 on volcanic eruptions and their effects on the Irish climate to see if there is a link just like there is with global temperatures because many significant volcanic eruptions just by looking at it briefly have preceded very cold times in Irish weather history like 2010, 1947 and 1816. There was a very significant eruption of Mount Sinabung just a few days ago which will likely impact the atmosphere come later 2018.
There was these hurricanes which were oddly similar in track, name and time to the 2010 hurricanes. Very strange coincidence! 2017 was a strong hurricane season and one of the worst on record. Strong hurricane seasons can be used as a methodology to tease colder Winters or at least some cold periods in the Winter even if it is mild overall. Why is this so? Hurricanes dump a lot of tropical air in the North Atlantic Ocean. This air can advect or flow up to the Arctic Circle and form a blocking area of high pressure up here which then allows cold to descend into the mid-latitudes where we are though it can go to North America, it can go to eastern Europe, it can go to Asia, it doesn't specifically have to go to us.
You don't need a strong hurricane season though just so ya know. 2009 was a very weak hurricane season and was followed by the coldest Winter in the British Isles since 1978-79. In northern Scotland, it was the coldest Winter on record with records going back to 1910.
2010 had a warm June and wet September which both tend to lead to colder Winters - warm Junes being far more changeable than wet Septembers. 2017 had both too.
This is not to do with 2010 but I found it interesting that I wanted to share it here. Remember all the similarities I had mentioned with February 2018's Polar Vortex split SSW of last week to January 1985's one? Well..... the most intriguing part of the January 1985 Polar Vortex split similarities with February 2018's one I find is the solar activity. They're nearly bang on the same part of the respective solar cycles, both about a year from true solar minimum and both before it. Just a fun fact I thought you'd like to know.
I hope this post is not too complicated for you.Photography site - https://www.sryanbruenphoto.com/
Weather photo portfolio - https://sryanbruen.myportfolio.com/weather-1
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Dundrum today. Photos by my friend Vxlks. He wanted me to share them here.
Photography site - https://www.sryanbruenphoto.com/
Weather photo portfolio - https://sryanbruen.myportfolio.com/weather-1
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Guys ye've gone very scientific here lately. Not criticising as the depth of knowledge is awesome,fair play! :pac:
But back to lay man's language. How is Kerry looking next week for the cold snap? Given that Kerry is always the least affected by heat and cold.
Though I'm not complaining as I'm a big fan of proper cold, dry cold 0 -
Another spotless day on the sun! We're really getting close to solar minimum!
https://twitter.com/solweather/status/967730908148019203Guys ye've gone very scientific here lately. Not criticising as the depth of knowledge is awesome,fair play! :pac:
But back to lay man's language. How is Kerry looking next week for the cold snap? Given that Kerry is always the least affected by heat and cold.
Though I'm not complaining as I'm a big fan of proper cold, dry cold
These are the threads for the cold spell if you'd like to join in the discussion. The technical thread is the second link where they talk about the model runs.
Discussion
https://www.boards.ie/vbulletin/showthread.php?t=2057844792&page=97
Technical discussion
https://www.boards.ie/vbulletin/showthread.php?t=2057844498&page=21
Snow preparations
https://www.boards.ie/vbulletin/showthread.php?t=2057844895&page=13
I'd advise to stick to MT's forecasts because it's going to be a historical and severe week, especially for the eastern half of the country. For you in the southwest, I think you will stay in the shelter of snow showers 'til around Thursday where you may get some and potentially blizzards for a time into Friday as a low mixes into the cold air from the south but there's a heck ton of uncertainty with this so focus on the here and now.Photography site - https://www.sryanbruenphoto.com/
Weather photo portfolio - https://sryanbruen.myportfolio.com/weather-1
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