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Winter 2017-18: Discussion
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It wasn't linked here so I missed it myself, but there's a thread for the potential snow over the next couple of days here: https://www.boards.ie/vbulletin/showthread.php?p=106114032#
PS. it would be great if people could link their new 'weather event' threads in the main seasonal one when they post them!
I keep forgetting to do that.
Photography site - https://www.sryanbruenphoto.com/
Weather photo portfolio - https://sryanbruen.myportfolio.com/weather-1
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I'm giving Kermit the side eye in this case
I promised JCX BXC I would do that though
Photography site - https://www.sryanbruenphoto.com/
Weather photo portfolio - https://sryanbruen.myportfolio.com/weather-1
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It wasn't linked here so I missed it myself, but there's a thread for the potential snow over the next couple of days here: https://www.boards.ie/vbulletin/showthread.php?p=106114032#
PS. it would be great if people could link their new 'weather event' threads in the main seasonal one when they post them!
I dont understand why you dont check the main weather thread
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Until the models fully catch on to the reversal of the winds I remain very sceptical of any benefits of a SSW.
Even though the models are next to useless and just piss you off anyway
. Photography site - https://www.sryanbruenphoto.com/
Weather photo portfolio - https://sryanbruen.myportfolio.com/weather-1
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SeaBreezes wrote: »Sryanbruen loving the updates fiercely interesting! No apologies and keep them coming thank you!! (I'm nowgoogling to see how cork fared in your mentioned cold spells :-) ) though can't complain,we got a dusting!
February 1902 started off with a big block of high pressure just to the north of us up to 1050mb with rather cool easterlies on its side.
By the 8th, the high pressure had retrogressed to Greenland and turned the winds into the north bringing down some bitterly cold air as well as a lot of snowfall. This lasted until the 13th which by then, an area of high pressure ridged in over us and brought very cold and frosty days with sunshine. There would be some mist and fog which would suppress the temperatures to below freezing during the daylight hours. Afterwards, it became much milder but this was an extremely cold start to the month so the milder weather did not offset the cold. I don't have an IMT (Irish Mean Temperature) figure for this month but the CET (Central England Temperature) for February 1902 was only 1.5c. Lairg, Scotland got down to -18.9c on February 14th.
Met Éireann has no information on this month unfortunately.
February 2009 didn't have much to offer in Cork but some parts of the country had their most significant snowfalls since February 1991 at this time. Too bad they didn't last as the second half of February 2009 was significantly mild and offset the cold. The IMT for February 2009 for instance was 5.6c which is +0.3c above the 1981-2010 average. England certainly got snowed under. This was the scene in London on February 2nd 2009:
I felt I should apologise because I posted several posts in succession after one another and it looked like I was clogging up the discussion thread. As I said, I only did it because there's so much interesting things going on in the weather scene that it's hard to resist - thus my large amount of posts within the past few weeks.
Due to how many times people ask about certain things like what does this mean for us? What effects does this have on our weather? Etc. I thought of making a full simple guide to all the methodology I use whether it's Sudden Stratospheric Warming, El Nino Southern Oscillation, Arctic Oscillation, North Atlantic Oscillation, solar activity etc. However, if I were to make that, I would need some help so the guide could be perfected and maybe add things that I don't know like the Madden Julian Oscillation which has me fascinated but for the life of me, I can't seem to catch the sense of what it means.
Thank you. Photography site - https://www.sryanbruenphoto.com/
Weather photo portfolio - https://sryanbruen.myportfolio.com/weather-1
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This graph shows you just how extreme the reversion of the mean zonal winds at 10hPa are going to drop to during the second half of February. The dark black line is the mean zonal wind speed for every season from 1978-79 to 2016-17. The blue line is 2016-17's mean zonal wind speeds. The red and pink line is where we've been with the mean zonal wind speeds for 2017-18. The gold line is where the mean zonal wind speeds are forecasted to go.
Let's take a look at how the season has fared since December in terms of the zonal winds. You can see by the red line that the zonal wind speeds were below the 1979-2016 average but were far from reversed, in much of December 2017. At the same time, this was when the coldest spell of the Winter - until February 2018 perhaps, took place. Coincidental? I think not. As we went on into January, we saw a massive spike up in the speeds of the zonal winds. Again at the same time, the weather became very unsettled with some storms striking our shores such as Eleanor, Fionn, David/Friedrich and Georgina. January was quite a strong month for mean zonal wind speeds with pretty much all the month above average though there was a day or two where they dropped somewhat. Early February here has continued to bring stronger than average zonal winds. However, as you can see from the gold line, the zonal winds are forecasted to drop significantly to a record breaking minimum level of speed.
There is nothing as extreme as the zonal wind reversion expected here in February 2018 after this Polar Vortex split and SSW that are currently taking place at this very moment. I really think people underestimate how extreme this event is.
Your minds should not blinded by the models like the ECM and even the GFS sometimes. I just use models sometimes as a tool to note trends on potential upcoming events. Like let's not forget these charts showing the significant drop in mean zonal wind speeds are models, so the models are kind of contradicting themselves once you look at it.
I'll say this for hopefully the last time, the only time similar to this Polar Vortex split was early 1985 which was followed by heavy snow and a freeze in much of Europe including Ireland and I had analysed that in the Irish Weather Statistics thread. The difference with the 1985 event and the outlooks for 2018 here is that in 1985, the eastern US had record breaking cold temperatures following that PV split event. Meanwhile, an area of high pressure is expected to ridge in these regions and bring milder conditions here in 2018.
Remember that 2/3 SSW events work in our favour too. I never said they're a guarantee for cold or snow for us but they have quite a high chance to go in favour of them here in Ireland.
Examples of SSW events:- March 2016 - Cold end to April with some snowfalls in the UK.
- January 2013 - Cold spell in January, fairly cold February and very cold March. Very cold Spring too.
- February 2010 - Coldest March since 2001 with a blizzard event towards the end.
- February 2008 - Some wintry outbreaks in March & April including a White Easter.
- January 2006 - Cold end to February and start to March.
- November 1962 - Coldest Winter of the 20th century.
- February 1989 - Very cold April.
Three of my favourite topics to discuss about Weather is Sudden Stratospheric Warming events, ENSO and solar activity albeit I'm still on the learning curve of each particularly the latter.
Photography site - https://www.sryanbruenphoto.com/
Weather photo portfolio - https://sryanbruen.myportfolio.com/weather-1
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Indeed this is an extreme event, and yeah 2/3 of All ssw's work in our favour, I suspect those odds are a fair bit higher again given the magnitude of this warming and zonal wind reversal. I would be more than surprised if we don't see some phenomenal synoptics over the next month.
I think it would be phenomenal in of itself seeing Europe fail for cold with the eastern US under a mild ridge of high pressure. Photography site - https://www.sryanbruenphoto.com/
Weather photo portfolio - https://sryanbruen.myportfolio.com/weather-1
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The ECM ensembles have backtracked to come in line to the ECM OP for the AO. By this, I mean that they are going towards the positive AO side for the rest of February. Around 1-3 ensembles are still going into negative AO territory. The GFS ensembles are pretty much 50/50 now for the AO for the rest of February, half of them going neutral to rather positive but not very positive and the rest go negative.
However, if we look at the GFS ensemble mean in FI, we get a chart like this with a very strong Greenland high. The height anomalies are nearly going off the chart with this high.
All this shows me honestly is the following:
1. The models continue to prove their uselessness. Even if we do get the cold spell, they will still flip-flop. You should know this from previous model watching experiences. When we're in a mild spell, the models want us to go into a cold spell - frequently showing phantom easterlies in FI. When we're in a cold spell, they want us to go into a mild spell. This is just the normal mindset of the models, nothing original here.
2. The models were showing too quick a tropospheric response to the SSW and PV split.
Nature will be what it wants to be regardless of what some "supercomputers" have to say.Photography site - https://www.sryanbruenphoto.com/
Weather photo portfolio - https://sryanbruen.myportfolio.com/weather-1
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