sryanbruen Registered User
#1,891

Pretty bullish UKMO forecast. Thanks for inspiring me RobertKK to look at it.

UK Outlook for Sunday 18 Feb 2018 to Tuesday 27 Feb 2018:
After a frosty start, Sunday is likely to stay dry and fine for most, especially in England and Wales, but the northwest will be more changeable with further wintry showers. Dry and bright weather will predominate in England and Wales throughout next week, with a greater than average chance of overnight frost. Light rain or drizzle is possible at times, mainly in north and west Scotland and perhaps Northern Ireland. Temperatures at the start of next week will be around average for the time of year, but there will be a trend toward colder weather by the end of the week and into the start of the following week, as prevailing winds turn easterly. Where this happens, wintry showers may develop near the east coast.

UK Outlook for Wednesday 28 Feb 2018 to Wednesday 14 Mar 2018:
As we move into the first week of March, it is likely to stay cold but often dry and settled with widespread overnight frost. There will be a greater chance than usual of easterly winds, which would bring very cold weather at times and the potential for some snowfall in eastern and even southern parts. In the second week of March there are indications that it may eventually become more unsettled and less cold, with the wettest weather and mildest temperatures likely to be in the south or the southwest of the UK.

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sryanbruen Registered User
#1,892

BLIZZARD7 said:

*there was a slight uptick in solar activity, we don't want to see this pick up anymore and I really hope this hasn't thrown a spanner in the works.


That's just the solar cycle being normal, remember the large sunspot number spike in early September? That was very normal with very weak solar cycles if you look at the solar data history.

We're not far off of solar minimum, could be later this year but most likely 2019 will be the year of solar minimum then all the thoughts will be going towards cold Winters!

nacho libre said:
I do recall Stuart Rampling blaming this for the infamous easterly that never was in December 2012. Is that really plausible? Can it override all other signals? I mean we are due to see warm air over the eastern usa and parts of Canada which usually correlates with colder outbreaks over the UK and Ireland. Everything seems to favour a cold outbreak, rather than a continuation of the current pattern.


Large difference with then is the stage in solar activity we're at. That was at a time of dropping off activity in between two peaks of solar maximum, this is nearing solar minimum.

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BLIZZARD7 Registered User
#1,893

sryanbruen said:
That's just the solar cycle being normal, remember the large sunspot number spike in early September? That was very normal with very weak solar cycles if you look at the solar data history.

We're not far off of solar minimum, could be later this year but most likely 2019 will be the year of solar minimum then all the thoughts will be going towards cold Winters!


Oh I know and very much agree, Just as nacho pointed out it was blamed in 2012 for our failed easterly at very short notice albeit that wasn't close to a solar minimum. Also in Dec 2012 there was more activity than now, Im just saying I hope we don't see a real unexpected spike.

I agree re next year and beyond, I do think we are on the way towards a maunder style minimum in time, the solar activity forecasts have been continually showing activity as higher than reality over the last decade. That is another discussion altogether though.

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Donegal Storm Registered User
#1,894

BLIZZARD7 said:
Oh I know and very much agree, Just as nacho pointed out it was blamed in 2012 for our failed easterly at very short notice albeit that wasn't close to a solar minimum. Also in Dec 2012 there was more activity than now, Im just saying I hope we don't see a real unexpected spike.

I agree re next year and beyond, I do think we are on the way towards a maunder style minimum in time, the solar activity forecasts have been continually showing activity as higher than reality over the last decade. That is another discussion altogether though.


Wasn't that just Piers Corbyn's excuse? I seem to recall him harping on about sun sausages or something as his excuse for a failed forecast

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George Sunsnow Registered User
#1,895

I’m losing interest in the run to run over analysis
No forecaster approaches weather looking for a particular outcome and my mindset despite being excited about what I think might happen works more like a forecaster than a particular outcome searcher
Obviously it will be disappointing if exciting outcomes don’t realize

I’m also expecting (as we all are) reams of faux output in the FI part of the models during this waiting phase and frankly have no interest in wafting through that waste of bytes
So count me out of these conversations for about a week at least

nacho libre Registered User
#1,896

Donegal Storm said:
Wasn't that just Piers Corbyn's excuse? I seem to recall him harping on about sun sausages or something as his excuse for a failed forecast


No. It was not just him. As I mentioned earlier, Stuart Rampling, the former chief forecaster on netweather, at the time cited an uptick in solar acitivty as to the reason why an easterly he championed did not come to pass. Regarding the latest solar acitivity i know we are coming close to a minimum, but a sudden rise or uptick in activity could skewer things- if it was a decisive factor back in 2012 then it could be again.

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sryanbruen Registered User
#1,897

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sryanbruen Registered User
#1,898

Stratosphere charts updated to the 13th February.

Small spike down at 10hPa.



Nearly going off the scale at 30hPa.

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pad199207 Registered User
#1,900
sryanbruen Registered User
#1,901

pad199207 said:
Very sensational tweet


What's sensational about it? You really don't see it everyday with cold pools going from east to west across the Atlantic than the other way round and the zonal winds being reversed.

All it shows is that this situation is highly unusual and a cold spell is around the corner.

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pad199207 Registered User
#1,902

sryanbruen said:
What's sensational about it? You really don't see it everyday with cold pools going from east to west across the Atlantic than the other way round and the zonal winds being reversed.

All it shows is that this situation is highly unusual and a cold spell is around the corner.


He tweets like as if it’s definitely going to happen.

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sryanbruen Registered User
#1,903

pad199207 said:
He tweets like as if it’s definitely going to happen.


And it is.

I've been saying this for days now.

I never said snowmaggedon or extreme cold either though.

Like a cold spell (in my definition) could easily be just high pressure with severe frosts like the second half of January 2011.

Judah is not a sensationalist, he's a climatologist.

sryanbruen Registered User
#1,904

Meanwhile, it seems the 18th is still up for grabs for the high pressure ascending from the south. Posting here because it's out of FI now.



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sryanbruen Registered User
#1,905

This chart is of the daily sunspot counts since August 17th last year, courtesy of Solar Weather and SILSO for the data. As has been mentioned by some posters here, the sunspot count has risen in the past week with solar activity reaching its highest level since early Autumn 2017 with this coming after a long run of spotless days from around January 21st to February 7th or so with just one little spike up around February 3rd. The fact that we're even getting these runs of spotless days - you don't have to go back far to find other runs of spotless days (look at early November for instance) - shows you how close we are to solar minimum come late 2018 or 2019. Notice the very large spike in early September 2017 I had mentioned which is very normal with very weak solar cycles such as Solar Cycles 12 (1878 to 1890), 16 (1923 to 1933), 5 (1798 to 1910) or 6 (1810 to 1823).

What has this got to do with our weather? Low solar activity Winters or Winters around/after solar minimum tend to be the coldest Winters. Examples include 2008-09, 2009-10, 2010-11, 1995-96, 1996-97, 1984-85, 1985-86, 1986-87, 1976-77, 1977-78, 1978-79, 1962-63, 1963-64, 1964-65, 1901-02, 1946-47, 1954-55, 1878-79.... the list goes on and on. Why is this so? Low solar activity (from a historical perspective) helps to form northern blocking over the Arctic Circle. According to a research project by Ida Johansson at Lund University in Sweden:

The blocking persistence over the Atlantic is on average three days longer in low solar activity years than during high solar activity years, while short-lived blockings are more frequent during high solar activity years. Also the spatial blocking patterns between high solar activity and low solar activity winters differ. During high solar activity blockings have a more westward location than during low solar activity years. Atlantic blockings during high solar activity and low solar activity years have a different impact on the climate. Blockings during low solar activity years result in cold European winters, while blockings during high solar activity years do not affect European winters as much because of the more westward location of the blocking centre.
In the Atlantic area blockings usually occur in the area of southern Greenland leading to that wind flow anomalies in this area which resemble the negative phase of the NAO. From around 1960 to 1990 when the NAO went from a negative to a positive state, the frequency of blockings over Greenland was decreasing. In addition, it has been suggested that the negative NAO phase in the early 1960s was associated with cold winters in Europe due to prolonged blocking events during this time period.
The possible mechanisms behind blockings are debated. Blockings might be a result of stratospherictropospheric coupling, which could explain the NAO extension into the stratosphere, during high solar activity winters. The question remains whether the different phases of the NAO lead to blockings or blockings lead to variations in the NAO. Different studies have shown contradicting results. Shabbar et al. (2001) proposed that the NAO forces blockings since it largely controls temperatures over ocean and landmasses in the Atlantic area. During a negative NAO temperature are warmer over the ocean and colder over land than during the positive phase. According to Shabbar et al. (2001) negative NAO conditions make it more favourable for persistent blockings to occur. Croci-Maspoli et al. (2007) instead stated that blockings might force variations in the NAO. Opposed to Shabbar et al. (2001) they proposed that persistent blockings could be causing the establishment of a negative NAO and also extend the occurrence of a negative NAO phase. According to Croci-Maspoli et al. (2007) blockings evolved during a positive NAO, dependent on their location, might also help sustain a positive NAO.


http://lup.lub.lu.se/luur/download?func=downloadFile&recordOId=5469871&fileOId=5469890

I highlighted a sentence there in bold because that's what I'm basically trying to say. We're at around the same phase of the solar cycle as late 2007 or early 2008.

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