Higher than average pressure across southern Greenland and central Russia, with lower than average pressure in the central North Atlantic help produce a fairly strong SW’ly mean flow for the month across the British Isles. The track of a number of tropical cyclones helped dig a path of lower anomalies from Florida by the look of it too.
October 2024 – Mean Pressure Read More »
The cold theme continued across southern Greenland & Iceland during October. It was particularly warm across Arctic Canada and to the north of Franz Józef Land in the Arctic ocean (+12°C), central parts of the United States where also much warmer than average (+5°C). Europe was generally 1-3 degrees above average. Spot my deliberate mistake in anomalies across Africa, if I had more than 14 subscribers I would bother to fix it. 😜
Globally, October 2024 was the second warmest in my DIYDIY Do It Yourself reanalysis series that extend back to 1948, fractionally behind 2023.
The daily mean global temperature has just overtaken those in October last year once again, setting more new daily records. Even without an El NinoEl Niño El Niño 'The Boy' is the warm phase of the El Niño–Southern Oscillation and is associated with a band of warm ocean water that develops in the central and east-central equatorial Pacific, the globe still continues to steadily warm. ☹
Oct 2024 – Global Temperature Read More »
There is only one chart in the whole month that doesn’t include a front of some kind in it. Spot the days when Mr Occlusion was on shift down at Exeter, the 9th is total nonsense.
Oct 2024 – Weather Log Read More »
One day I’ll get around to adding some temperature and rainfall anomalies to these climate statistics, until then all I can say is October 2024 was a fairly average month for our part of Ross-shire.
Oct 2024 – Strathpeffer Read More »
The mean temperature for October 2024 in central England was 11.5°C, making it +0.7°C warmer than the 1991-2020 LTALTA Long Term Average. This is usually defined as a 30 year period by the WMO.. The month was marked by a short cold spell from the 10th to the 14th, after that temperatures were generally several degrees above the LTA.
October 2024 – CET Read More »
Surprisingly, October ended up a rather average kind of month as far as sunshine, precipitation and temperature were concerned for the UKUK The United Kingdom of Great Britain and Northern Ireland, commonly known as the United Kingdom (UK) or Britain, is a country in Europe, off the north-western coast of the continental mainland. It comprises England, Scotland, Wales and Northern Ireland. as whole. Regionally, the northwest was drier than average, and the northeast sunnier than average. Mean temperature anomalies across the nation, which were slightly above the LTALTA Long Term Average. This is usually defined as a 30 year period by the WMO., were within 0.3°C of each other. As Greavies would remark, it’s a funny old game Saint😜
October 2024 – Weather Summary Read More »
A terrific display of orographic lee wave cloud across NENE North East Scotland that extends eastward into Norway. Unusually, all the LCBR across northeast Scotland are reporting zilch in terms of medium or upper cloud heights this lunchtime, so I had to revert to some Weather Watcher images as a last resort.
These Weather Watcher pictures show the base of the lenticular ACAC Altocumulus clouds are generally associated with settled weather and will normally appear white or grey with shading. Height of base: 7,000 - 18,000 ft Shape: Bands or areas of individual cells Latin: altum - height; cumulus - heap Altocumulus clouds are small mid-level layers or patches of clouds, called cloudlets, which most commonly exist in the shape of rounded clumps. There are many varieties of altocumulus, however, meaning they can appear in a range of shapes. Altocumulus are made up of a mix of ice and water, giving them a slightly more ethereal appearance than the big and fluffy lower level cumulus./CICI Cloud, comprised of ice crystals that form wispy filamentous tufted streaks or ‘mare's tails’ at high altitude usually 16,500 to 45,000 ft./CSCS Ice cloud forming a thin, more or less uniform semi-translucent layer at high altitude, usually 16,500 to 45,000 ft. cloud is very high, maybe 18,000 ft or higher by the look of it.
31 Oct 2024 – Wave cloud downwind of NE Scotland Read More »
Not a particularly memorable named storm, although it did manage to come in at #15 in the maximum hourly gale index of named storms since 2015.
20 Oct 2024 – Storm Ashley Read More »
I’ll warn you now this is a crazy post 😜. For some reason I got to wondering how much of an affect the friction from a stormy sea with large winds a big swell and large waves can have on wind speeds measured by an anemometer out in the open ocean? The reason I ask is because in the recent named storm ‘Ashley’ on the 20th of October 2024, the winds from the Weather Buoy known as K4, seemed to be rather on the low side. My memory is probably playing tricks here, but I remember when plotting any of the Ocean Weather Ships on a chart in stormy weather as an assistant, it wasn’t unusual for me to plot mean speeds of 50 knots or more. That’s when I got to wondering about surface friction and the height of the anemometer, and what effect friction would have on wind speeds? The height of the anemometer may have been 60 feet or more above the ocean surface on a weathership, but on a weather buoy, that might be no more than 20 feet. It may be fairly academic now because the days of weather ships have long since passed, but there are still hundreds of ship and probably thousands of weather buoys observations made each hour across the world, so I wonder if any adjustment at all is made to those from buoys? I did warn you that this post was crazy.😉
PS If you want to find out more about Ocean Weather Ships maintained by the Met OfficeUKMO The Meteorological Office is the United Kingdom's national weather service. It is an executive agency and trading fund of the Department for Business, Energy and Industrial Strategy Ican recommend this great site WeatherShips.com
Wind speeds from Buoys and Weatherships Read More »
Iceland has been rather cold for much of this year. The reason I’ve put it down to was persistent NW’ly winds flowing down from off Greenland ice cap. This month however, a tongue of colder water SSTSST Sea Surface Temperatures has extended E’NENE North East from the coast of SE Greenland and wrapped itself around Iceland’s north and east coast. You can see the effects of this if you look at temperature anomalies so far this October for Iceland. The cold month we’ve seen across much of the UKUK The United Kingdom of Great Britain and Northern Ireland, commonly known as the United Kingdom (UK) or Britain, is a country in Europe, off the north-western coast of the continental mainland. It comprises England, Scotland, Wales and Northern Ireland., and which the media love to describe as ‘rather chilly’, may also be a symptom of the colder air across Iceland and those same NW’ly winds.
How long these low SST will continue around Iceland is anyone’s guess, and what if any effect this will have on the coming winter. One thing I have noticed for some time in the long-range 16 to 30 day text forecast from the UKMOUKMO The Meteorological Office is the United Kingdom's national weather service. It is an executive agency and trading fund of the Department for Business, Energy and Industrial Strategy, is the mention of higher pressure to the northwest of the UK which might be in somehow linked.
Towards mid-November, high pressure may become more focussed towards the northwest of the UK, allowing a gradual trend towards colder and perhaps more unsettled conditions, especially in more southern and eastern areas.
UKMO
16 Oct 2024
The reason why Iceland has been so cold this month Read More »
Only three hourly Synops I’m afraid, and many of them missing from the worst affected regions. At a glance, and from this limited SYNOPSYNOP SYNOP (surface synoptic observations) is a numerical code (called FM-12 by WMO) used for reporting weather observations made by manned and automated weather stations. SYNOP reports are typically mad hourly and consist of groups of numbers (and slashes where data is not available) describing general weather information, such as the temperature, barometric pressure and visibility at a weather station. data, although it looked a pretty windy night, you wouldn’t have thought it had been as severe as it was across the southeast of England. I’ve no idea if my hind sight analysis was anywhere close to the analysis on the day. I was an observer at Kinloss at the time, and missed all the excitement after being posted to Scotland that summer.
16 Oct 1987 – The Great Storm Read More »
I was on the day shift as a weather observer at RAF Kinloss in Morayshire on the 13th of March 1989. We had got quite blase about seeing aurora since we moved to northern Scotland in 1987. The display of the 13th March 1989 was quite different though, not only did it start very early in the evening, but also started on the southern horizon! Not only that, the animated multi-coloured coronal structures extended right up to the zenith. I filled the remarks column of the daily register with details, and added the special 9 group at the end of the SYNOPSYNOP SYNOP (surface synoptic observations) is a numerical code (called FM-12 by WMO) used for reporting weather observations made by manned and automated weather stations. SYNOP reports are typically mad hourly and consist of groups of numbers (and slashes where data is not available) describing general weather information, such as the temperature, barometric pressure and visibility at a weather station. report for direction and intensity or something like (memory fails), which believe it or not the WMOWMO The World Meteorological Organisation is a specialized agency of the United Nations responsible for promoting international cooperation on atmospheric science, climatology, hydrology and geophysics. deprecated!. The night shift came in I drove home and alerted all our neighbours in our cul-de-sac as the display was still in full swing. Quite memorable. Now observing the aurora is all the rage and the UKMOUKMO The Meteorological Office is the United Kingdom's national weather service. It is an executive agency and trading fund of the Department for Business, Energy and Industrial Strategy are now into ‘Space Weather’ how things have changed in the last 35 years. I had a Canon A1 film camera back then, but I was probably just too excited watching it to get my camera out, and was content just to marvel at it.
I couldn’t quite fix the date it occurred, until I came across this letter from R.J.Livesey that mentioned the display and which I’ve included.
13 March 1989 – Spectacular auroral display Read More »
This post is more of a reminder to myself about an application I wrote to display a grid of charts it downloads from Wetterzentrale. You can choose to display CFSCFS The Climate Forecast System or coupled forecast system (CFS) is a medium to long range numerical weather prediction and a climate model run by the National Centers for Environmental Prediction (NCEP) to bridge weather and climate timescales. Version 2 became operational as CFSv2 in 2011., ERAERA ERA stands for 'ECMWF Re-Analysis' and refers to a series of research projects at ECMWF which produced various datasets (ERA-Interim, ERA-40, etcetera). or NOAANOAA NOAA is an agency in the Department of Commerce that maps the oceans and conserves their living resources; predicts changes to the earth's environment; provides weather reports and forecasts floods and hurricanes and other natural disasters related to weather. reanalysis charts either as charts of isobars overlaid over colour filled contours of 500 hPahPa A Hectopascal is the SI unit of pressure and identical to the Millibar heights, or as charts of isolines of 850 hPa geopotential heights, overlaid on colour filled contours of 850 hPa temperature. I think it produces a pretty useful grid of charts to view a month, or a season, but in truth I haven’t used it that much in the last 12 years. The example above displays surface pressure charts for Christmas day.
The grid of images above, is for daily MSLPMSLP Mean sea level pressure is the pressure at sea level, or, when measured at a given elevation on land, the station pressure reduced to sea level assuming an isothermal layer at the station temperature. and daily 500 hPa geopotential heights for each day of the infamous winter of 1962-63.
The other innovative thing that I added to the application, was a colour analyser (above image). This does a lookup on the colour of each pixel across the map of the British Isles in the downloaded image, and calculates an overall average which it uses to plot a graph and fill a table with the daily 850 hPa temperature or the 500 hPa geopotential height. A crude but quite effect way of gauging just how warm or cold it is on any given day.
There are problems with the app, but out of my control, in that Wetterzentrale for some years, use a slightly different resolution and size for their images. I could fix it but it’s fiddly. They also seem now not to load the ERA reanalysis images on their server. Who knows for how much longer they’ll maintain the CFS and NOAA images, it would be a real loss if this went.
Winter 1963 – Daily MSLP and 500 hPa heights Read More »
I had previously plotted correlations between LWTLWT Lamb Weather Types are often used in UK-based analyses, with individual weather patterns based on the eight primary cardinal directions (N, NE, E, SE, S, SW, W, NW) plus cyclonic (C), anticyclonic (A) and unclassified (U) types. and CETCET Central England Temperature, so the obvious thing to do now was to plot correlation charts using daily LWT types and daily rainfall from the UKPUKP UKP is a gridded datasets of UK regional precipitation. regional rainfall series, which I download from the UKMOUKMO The Meteorological Office is the United Kingdom's national weather service. It is an executive agency and trading fund of the Department for Business, Energy and Industrial Strategy. It turned out to be even less exciting than a lot of the climate statistics I’ve produced before, in that it just confirmed what you could easily deduce by using a little common sense in that anticyclonic weather types are drier than cyclonic types. 🙂
Generally westerly types come in second wettest, using an average for the whole year.
Depending on what region you look at, easterly & northerly types are sometimes drier than anticyclonic types. The reason for that is that the results are likely skewed for easterly and northerly types because they occur much less frequently than do anticyclonic types.
Westerly types in Scotland (see below) seem to peak in January, at close to 2 mm per day, but fall to a low of 0.4 mm in May, again a fairly obvious correlation.
Lamb Weather Types and UKP correlations Read More »
I wrote some code a long while ago now that correlated temperatures in the Central England with the corresponding weather type from the objective Lamb Weather Type series. I compared just the six pure types, anticyclonic, cyclonic, northerly, easterly, southerly and westerly. The application allows you to correlate using the mean, maximum or minimum temperatures with the LWTLWT Lamb Weather Types are often used in UK-based analyses, with individual weather patterns based on the eight primary cardinal directions (N, NE, E, SE, S, SW, W, NW) plus cyclonic (C), anticyclonic (A) and unclassified (U) types. on that day. I may have published these charts in a previous blog but I forget, so here they are again 😉
Cyclonic types, whatever the time of years generally seem to be associated with colder anomalies.
Mean temperatures in anticyclonic types are generally only warmer in the months of June or July, otherwise they are invariably colder. See below for charts of maximum and minimum CETs.
As you would expect northerly LWT types always produce colder mean temperatures in central England.
Not surprisingly E types are much colder from October to May, but a little warmer in the extended summer months.
Southerly types are warmer from around April till the end of October, otherwise they produce lower than average mean temperatures.
Westerly types in contrast to N, S, and E types are usually a little colder in the summer, from mid-April to the start of October, in winter they are nearly always milder.
Above are charts for mean maximum and mean minimum temperatures for anticyclonic types, the results of which are a little surprising to me, in that the maximum correlation in summer months is much lower than I imagined it would be, because of course you naturally assume the A type, must be the one favoured for many of the very warm spells in summer. I calculated all the anomalies in the correlations using the 1878-2023 long-term averages, which I thought was the fairest way of doing things, but maybe I was wrong. Perhaps if I revisit this code again I’ll add the frequency each weather type occurs. 😜
Lamb Weather Type and Central England Temperature correlations Read More »
I’ve added some code to my LWTLWT Lamb Weather Types are often used in UK-based analyses, with individual weather patterns based on the eight primary cardinal directions (N, NE, E, SE, S, SW, W, NW) plus cyclonic (C), anticyclonic (A) and unclassified (U) types. application to display graphs of 365 day moving averages for some of the daily indices that the objective series generate. I thought it might be easier to pick out trends using an extended period like this, although the application is flexible enough to allow shorter periods. At a glance you can see that mean MSLPMSLP Mean sea level pressure is the pressure at sea level, or, when measured at a given elevation on land, the station pressure reduced to sea level assuming an isothermal layer at the station temperature. over the last 10 years across the British Isles is currently at its lowest at the moment, and positive cyclonic vorticity has also been at a ten year high in 2024 as well. What it all means remains a mystery but it kept me busy this afternoon. 😜
Objective Lamb Weather Types – 365 day averages Read More »
I’ve just refactored the main window in my Vantage Pro database application, and added a three-line footer to provide means and extremes for whatever month or season the data has been filtered on.
Sep 2024 – Strathpeffer Read More »
Circulation wise September was a rather blocked and meridional sort of month, with winds from N or E. Mainly anticyclonic from the 12th to the 19th, otherwise rather cyclonic at times, especially during the last week.
Not a great deal of difference from the results of the Summer index for 2024 really, with East Anglia still having the highest index and Northern Scotland the lowest. The result for the extended summer in Northern Scotland were much improved though, from a summer index of -27 to and extended summer index of -7, thanks to a spell of good weather and record temperatures in May, and another settled warm spell in mid September.
2024 – Extended Summer Index [MJJAS] Read More »
The mean temperature of 14.0°C made it the coldest since 2020, and 0.2°C below the 1991-2020 LTALTA Long Term Average. This is usually defined as a 30 year period by the WMO.. This was the third below average month in 2024 so far in central England, in a year which globally almost certainly will be the warmest on record.
Sep 2024 – Central England Temperatures Read More »
Unusually high pressure in September to the southwest of Iceland and Greenland (+8 hPahPa A Hectopascal is the SI unit of pressure and identical to the Millibar) and across Ukraine (+11 hPa). This effectively neutralised the usual Icelandic low, effectively pushing a band of lower pressure from northern France to the Black Sea. That left the British Isles in a col as far as mean pressure for the whole month was concerned, which doesn’t quite tell the whole story.
Sep 2024 – MSLP Anomalies Read More »
A month at first glance dominated by colder than average temperatures. Yet another cold month across Iceland, with what’s fast becoming the normal NW-SE temperature gradient across the British Isles.
Sep 2024 – Temp Anomalies Read More »
Four days of thunderstorms, heavy showers and rain across the south all due to an upper cold pool that migrated westward.
20-23 September – Wet spell Read More »
I noticed recently that the UKMOUKMO The Meteorological Office is the United Kingdom's national weather service. It is an executive agency and trading fund of the Department for Business, Energy and Industrial Strategy have started to publish and maintain on their website, data files of daily mean maximum and minimum temperatures from the stations that they have used to calculate the composite Central England Temperatures since 1878. I had given up hope of ever seeing this data, which gives a better insight on the machinations the UKMO go through to produce the series each day. What would Philip Eden have given to access this CETCET Central England Temperature data! 😜 As you can see from the above screen shot above I’ve added a new viewer to my Daily CET application to download, parse and display the data in tabular form and as plotted charts.
At the moment the CET series uses temperatures from the following stations:
Each of these site has a buddy site, so if it fails to report, the temperature from the other site can be used in its place. This happens a lot more frequently that I ever realised. The data files do include a file of eight boolean flags to identify which site were used for which day. The table below is for the CET values up to the 4 September 2024. I’ve highlighted the sites that are being used in the table in bold, and used grey text for those that aren’t. The provisional daily CET is in the 2nd from right column, and the difference column on the right, is the difference between the provisional mean and the one calculated from the raw data from stations being used. The difference is probably the adjustment applied to each stations temperature for the effects of urbanisation.
The table below is from 2004, and I think marks the point when Stonyhurst and Pershore replaced Squires Gate/Ringway and Malvern in the series. Whoever in the Met OfficeUKMO The Meteorological Office is the United Kingdom's national weather service. It is an executive agency and trading fund of the Department for Business, Energy and Industrial Strategy thought temperatures from a coastal site like Blackpool was a good site to represent central England beats me, although that might be down to how Manley constructed his original monthly series. I think the Stonyhurst temperature record is second only to Oxford in England in length, and had been used for many years before this.
The latest sites all have their own peculiarities as you can see from the graph below of 30 day average daily maximum temperatures. Stonyhurst is usually the coldest of the latest three sites being used to calculate daily CET values, with Pershore usually the warmest, with Rothamsted usually trailing a little behind Pershore. All this is obviously weather dependent. So the composite CET for the warmest day in the whole CET series in July 2022 ends up being in no mans land temperature wise.
Similarly in this graph of 30 day average daily minimum temperatures from 2010, Stonyhurst is usually coldest, although the three minimum series are more closely bound than the maximum. You can see that in the cold December of 2010, Pershore is fractionally colder than Stonyhurst for a while.
The table below shows how the CET series has changed at times in recent years, and how the buddy system comes into play when temperature data goes missing.
Central England Temperatures – Raw station data Read More »
