Archive charts
-
20-11-2023 11:36PM#1
Comments
-
-
-
-
The most "eye candy" chart in terms of high latitude blocking for me in Europe goes to February 1895.
A total reversal of the normal flow with easterly winds from Russia all the way to North America with blocking from Canada to Russia. This resulting in one of the most intense cold spells Ireland has had since reliable records began.
28 February 2018 gets some points too, somewhat similar but I'd argue not quite as extreme.
January 1940 is a crazy one for Arctic blocking and see that black spot over northeast Europe, that's 850hPa temperatures as low as -43C!
Photography site - https://sryanbruenphoto.com/
7 -
I love this one, day two of a three day snowstorm in 1917 and it doesn’t even look particularly cold!
It looks like a southeasterly but in a ‘battle ground’ situation the isobars are aligned se-nw with the wind easterly. The big snowstorms of Feb 1947 and Jan 1982 also look like southeasterlies.
3 -
Advertisement
-
-
-
-
-
This must have been due to our good friend the Polar low.
http://www.irishidentity.com/extras/weather/stories/bigsnow.htm
2 -
Advertisement
-
-
-
-
The whole month was virtually easterly though high pressure did collapse over us by mid-month which only led to more severe frosts. It became a mid-Atlantic ridge feature by the end into early March. Mind that the cold had been ongoing since mid-January 1895 too. Here's a link to my old 1895 historic post as a reminder though all the charts are gone because of the Boards "makeover" 🙄 https://www.boards.ie/discussion/comment/112343684#Comment_112343684
Here's some more "eye candy" charts.
18th January 1881, a deep Channel low bumping into entrenched cold air (Ireland's most severe cold spell on reliable records) and a bitterly cold strong easterly wind. Not much is known about the exact numbers of snow depths in Ireland during this month but given the severity of the frosts regularly in the minus double digits widely, you would think there was a lot. Markree set the Irish national record low this month 2 days prior with -19.1C and had 13 days with mins of -10C or lower, almost half the month. This low would deliver one of southern England's biggest snow events on record.
A proper Scandi and beast from the east on 1st February 1956. An extremely cold month for Europe. Marseilles, France had a monthly mean temperature of -1.2C, this was over 3.2C colder than its second coldest month showing how extreme it was. Ireland often being on the periphery but it was a cold month here too and it began severe.
And for the northern folk, a polar low within an entrenched cold airmass just after Christmas 2000 😏 Knock Airport 17cm and Aldergrove 19cm from this. Over 7cm fell in one hour at Knock Airport on the afternoon of the 27th December, very heavy snow.
Photography site - https://sryanbruenphoto.com/
2 -
-
-
-
how the polar low northerly blast of January 1958 began, a big high in its usual place quickly moved towards Greenland and the flood gates opened!
this is what we want to happen now but not a snowballs chance in hell of this happening in a 21st century winter, maybe late March or April?
1 -
-
-
Advertisement
-
The very cold February 1969 begins.
a northerly (with a Polar low down down eastern England) develops in only two days … compare that with now when trying to get a northerly/Greenland block is like getting wisdom teeth extracted!
1 -
It's mad how things could change so quickly looking at the charts posted in this thread . Take early Jan 1977. 4th Jan a poor chart for cold weather but a few days later by the 9th all change. These days we keep getting stuck in ruts that can go on for weeks.
1 -
This 1960 one was likely aided by a major SSW through early to mid-January 1960. Effects from it were being felt as far out as mid-March at least in terms of the AO.
The infamous 1947 freeze was also probably caused by a major SSW PV split as recent ERA-5 reanalysis has come out to reveal a significant warming of the stratosphere through January 1947. Not sure where they get the data from to be able to reanalyse that as stratospheric records began in the 1950s I'd have thought but there we are. Doesn't surprise me if true though as we were pretty much in easterly winds all the way from the third week of January to the first week of March which is unprecedented, at least in reliable records, for longevity for this part of the world.
Post edited by sryanbruen onPhotography site - https://sryanbruenphoto.com/
2 -
-
-
-
I find with the strongest Azores Highs (and simultaneously, a very very positive NAO), they tend to be more "distorted" rather than flat so we get more of a NW'ly influence which can bring wintry weather but of course rarely anything too significant and any snow is very wet in nature, difficult to accumulate. That's not a confirmed fact though, it's just an anecdote of mine. Delves mainly from the fact that the most +NAO winter on record was 2014-15 and 1983-84 was also up there, both were very NW'ly driven. One other occasion that had a massive 1050mb+ Azores High similar to what is expected on some model runs for December 2023 is January 2003 which had exceptionally mild conditions followed by a northerly blast that affected the UK more but was noteworthy in that era which was very lacklustre for winter weather too.
February 1986 didn't have any stratospheric feedback as far as I'm aware @nacho libre. Zonal winds were persistently strong throughout that 1985-86 season until mid-March (at least in the upper strat, there was a significant deceleration in the bottom strat during November 1985) when the final warming occurred and it was quite a dynamic one which likely played a part in how April 1986 was so cold. More often than not, I find the significant blocking periods tend to have some kind of stratospheric feedback with the MJO also playing a role.
Here's a "forgotten" beast from the east. Yes it's 1894, I know 😂 but forgotten I mean by even historians. It came within an otherwise mostly mild winter, at least for the era.
Birr Castle had a max of -7.3C on 6th January 1894 with a minimum temp of -15.6C. It was quite short-lived as shown by its daily temp returns.
1st 4.8C, -2.3C
2nd 2.0C, -2.1C
3rd 1.9C, -1.7C
4th 1.2C, -3.7C
5th -2.5C, -8.1C
6th -7.3C, -15.6C
7th -0.1C, -8.4C
8th 5.4C, -3.4C
9th 8.2C, 2.1C
10th 11.6C, 7.4C
Its mean monthly temp was -3.0C after the first 7 days. That had risen to -0.5C in just 3 days to the 10th.
Photography site - https://sryanbruenphoto.com/
2 -
-
-
Advertisement
-
