Mad about the weather

Oxford Radcliffe Observatory Climate Viewer

The Oxford Radcliffe Observatory have finally decided to release their daily climate readings they’ve been making since 1815, you can download the CSVCSV A data file using Comma Separated Variable format. file for it from here. I tried emailing them for many years urging them to do this, but I never got a reply. It seems bizarre to me that in a warming world like ours why they would be so protective of what is one of the longest temperature series in the world. They’re not giving that much away just 75,726 days of maximum, minimum, grass minimum, rainfall and sunshine values, but if you like me love climate data, then it’s like you’ve stumbled on the mother lode. They could have included snow days, even perhaps days of thunder, gale or fog. I see that Ed Hawkins has now got a load of volunteers to digitise and add daily pressure readings from 1828 and 1856. It will be interesting to see whether that spurs the observatory on to updating the latest CSV file beyond the 30th of April 2022 to include 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., I know my recent email has fell on deaf ears once again. I’ve kind of worked up with the coding because it’s very disappointing that the data is not updated on a regular basis. Here are some screenshots from some of the other viewers in my Oxford Climate Viewer windows application, it’s amazing what you can do with such little data.😉

Daily Precipitation Viewer and the wet Winter [DJFDJF Meteorological Winter comprising the months of December, January & February] of 2020-21

Daily Sunshine and the Summer [JJAJJA Meteorological Summer comprising the months June, July & August] of 1976

Daily Temperature viewer and the cold Winter [DJF] of 1962-63

365 day average mean temperatures 1991-2022
Showing a warming of 0.12°C per decade in that time
_{*must fix that title}

Autumn [SONSON Meteorological Autumn - September, October and November] precipitation 1826-2022
Wetter by 2.7 mm/decade in that time

Annual mean temperatures 1815-2022
A rise of 0.09°C/decade in the last 207 years

Finally an Annual, Seasonal and Monthly Grid viewer.

The observatory Site

These three images from Google show how the enclosure at the observatory looks these days. It appears that they may have been hosting the Great British Bake Off in that marquee when Google came snooping around for these picture. It’s no wonder the temperatures that day were so high, especially when Prue Leith thought she would demonstrate how to flambe one of her deserts. Seriously though the observatory has been surrounded by houses and streets from early Victorian times, so I acn’t see that urbanisation of the immediate site has ever been that big a problem because it’s also been urbanised.

Hourly Rainfall Viewer

I hadn’t realised how many hourly rainfall reports were available in 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. reports I download from OGIMET, so I finally decided to write an additional dedicated viewer to my SYNOP application to view them with. The viewer consists of the usual interlinked data grid to view each hourly total, a map to plot those hourly values on, and a chart in the form of a hyetograph for the selected station. I’ve added the ability to produce an animated GIF of the map as it steps through each selected hour. I’ll add an animation when I get a suitable weather situation. I haven’t checked to see how closely the hourly totals match up to the 6, 12, and 24 hourly reported values but you would think if the AWSAWS Automatic Weather Station software was doing its job right they should be the same. The only trouble is hourly values of one mm or more are in whole numbers.
The next logical step would be to add hourly data from the EAEA The Environment Agency is a non-departmental public body, established in 1996 and sponsored by the United Kingdom government's Department for Environment, Food and Rural Affairs, with responsibilities relating to the protection and enhancement of the environment in England., SEPASEPA The Scottish Environment Protection Agency is Scotland's principal environmental regulator, protecting and improving Scotland's environment. and whatever the Welsh versions called, I do have separate applications for the EA and the SEPA but it might be quite a task to meld three into one.

The late Summer and Autumn of 2023

Just a quick note to make a note about how late an Autumn it’s been in 2023. Its now past mid October, and many trees here in StrathpefferStrathpeffer Strathpeffer (Scottish Gaelic: Srath Pheofhair) is a village and spa town in Easter Ross, Highland, Scotland, with a population of 1,469. are still have more green leaves than they do brown, and although the Service and Birch tree have lost most of their leaves, others have not. I witnessed late, even very late Autumns in Devon over the years, but not here in Scotland since we returned five years ago. Why is Autumn late? Simple enough, summer was pushed into September and early October by a rather cold mid-summer as these anomaly charts show. The numbers in the pink boxes by the way are the mean anomalies for the gridded temperatures for the whole map, the graph is for temperatures at the grid point 57.5N 5W, the closest to home. It does make you wonder if meteorological summer should now be a four month period rather than a three which also includes September, whilst Autumn should now include December. By the way the title of that graph should read Mean Temperatures and not anomalies and another thing to put right.

Heavy rain across Scotland | 6-8 October 2023

A very wet weekend across Scotland with many reports of flooding on both the road and rail network. It never picked up much news coverage nationally or in Scotland itself. That’s not surprising because most local news is done by posting stories, and particular images and videos, on social media these days. The idea of having reporters on the ground to chase up and write about stories like this have almost gone.
What amazes me that is we would rather close the railways down for the weekend rather than fix the problem. What remains of our railway network is a vital infrastructure and should not be prone to flooding like this. I don’t believe that in the 21st century that we can’t invest and install adequate drainage to prevent the ever increasing number of events like this from happening.

There was upwards of 200 mm on the high ground in the wettest places as you can see in these estimates from weather radar. I think we ended up with ~87 mm in around 48 hours here in StrathpefferStrathpeffer Strathpeffer (Scottish Gaelic: Srath Pheofhair) is a village and spa town in Easter Ross, Highland, Scotland, with a population of 1,469.. Although the ground was temporarily saturated and did flood for a while, it wasn’t long before the ground absorbed it, because up until now this year has been much drier than average.
It all came in stark contrast to the sunny skies and very warm weather further south across England, Wales and Ireland, with temperatures of 26°C or higher, whilst in Scotland, sub-zero temperatures and snow was reported on the highest of the Cairngorms.
Finally this event, even though it didn’t have any strong winds associated with it, should have been declared a named storm. Why it wasn’t defies any logic, especially when two amber warnings were issued for it. Most of the public will have already forgotten about storm Agnes, but memories of this heavy rain and flooding might stick around a bit longer.

The rather cold summer of 2023 in Iceland

One country in Europe that’s bucked the trend of a warm summer in 2023 was Iceland. I’ve noticed this in the monthly anomaly charts for mean temperature that I produce, so I decided to spruce up my chart grid viewer to see if I was right in my assumption, and as you can see in this chart of weekly mean anomalies I was. What caused it is may have been persistent high pressure across the Greenland ice cap to the northwest of Iceland, and a shift southward of the Icelandic low, which in turn allowed more days of northerly or north-westerly flows and hence the lower than average temperatures.

It’s not easy to verify these findings because even the Icelandic 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 site offers no real clues to how they categorised this summer’s temperatures. If you’re by any chance reading this in Iceland, please let me know how you found it😉

Hovmöller diagram

I had never heard what an Hovmöller diagram was until I watched the Deep Dive video produced 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 and put out on their Youtube channel yesterday. The Hovmöller diagram was first introduced by Ernest Aabo Hovmöller (1912-2008), a Danish meteorologist, in a paper that he published in 1949. I had seen charts like it before used to display climate data, but hadn’t realised that they had a name. In reality they’re very similar to a heat map as far as I can see, but I decided to see if I could reproduce one in software that was as similar as possible to the one that Alex Deakin showed.
As you can see the X-axis displays values of longitude for a fixed line of latitude, in this case 55° north. The Y-axis displays dates over the last month. In the Hovmöller diagram above I’ve displaid 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. values from six hourly reanalysis data. It clearly shows various anticyclonic spells in red and hot spots of cyclonicity in blue. I think it will come in very handy as another way of looking at global MSLP or temperature climate data over a longer period although I’ve still to write the code for that😉

September 2023 – When anomaly charts hide the real picture

I was watching the Deep Dive video produced by 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, and presented so well by Alex Deakin about the weather in September 2023 on Youtube as you do. He showed two anomaly charts for 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., one for the first half of September and the other for the second half that showed how anomaly charts for the whole month can sometimes be misleading. In this case it was how the remarkable warm spell in the first half of the month contrasted with the more mobile second half. The resulting anomaly chart for the whole of the September cancelled out the anticyclonic SE’ly in the first half that brought all the high temperatures.

September 2023 – Global Temperatures

For the fourth month in a row global temperatures have set another new monthly record for warmth. September is perhaps the most remarkable of the four in my DIYDIY Do It Yourself global temperatures series, exceeding the previous highest in 2016 by a massive, in global temperature terms that is, of 0.24°C. The question that immediately springs to mind is when will this run of new extremes come to an end? Maybe when it comes full cycle in June of 2024, or who knows if the 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 is still running it will just continue.

Currently, on the 30th of September, the daily mean global temperature is in open water on the graph above way higher than in any of the previous daily temperatures since 1948. What’s driving the sharp rise in global temperatures are the higher than average SSTSST Sea Surface Temperatures in the central Pacific Ocean. The La NinaLa Niña La Niña is an oceanic and atmospheric phenomenon that is the colder counterpart of El Niño, as part of the broader El Niño–Southern Oscillation climate pattern. The name La Niña originates from Spanish for "the girl", by analogy to El Niño, meaning "the boy". In the past, it was also called an anti-El Niño[1] and El Viejo, meaning "the old man." event which had been keeping a check on global temperatures until earlier this year has gone, replaced by a strengthening El Nino.

September 2023 – Mean MSLP

A classic mean pressure chart for September that bears a striking resemblance to charts of mean pressure for the whole year that you might see in many geography textbooks. Pressure was much lower across the eastern Atlantic (-5hPa) than usual, and much higher across the Ukraine and eastern Russia (+6hPa), resulting in a fairly strong SW’ly flow across the country.

September 2023 – Mean Temperature Anomalies

A very much warmer September than average across much of central Europe and northeast Russia. A colder than average month yet again across Iceland, Greenland, North Africa and Iran.

September 2023 – Joint second warmest in UK

The mean temperature 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. for September 2023 in the gridded series was 15.2°C which equalled that of 2006.

1 Comment / October 2, 2023

Climate, Temperature

September 2023 – Joint second warmest in UK Read More »

September 2023 – Weather Summary

A very mild, rather wet & rather sunny month.

September 2023 warmest in Central England

The mean of 17.0°C was fractionally higher than that of September 2006. The CETCET Central England Temperature value wasn’t held back by lower temperatures across Scotland as was the gridded data series.

Late September SST anomalies 2022 & 2023

The southeast of the North Sea and Baltic remain remarkably warm still with anomalies widely of +3°C above the LTALTA Long Term Average. This is usually defined as a 30 year period by the WMO.. Is the warm summer of 2023 across Europe a product of these high SSTSST Sea Surface Temperatures, or as seems likely, these high SST are just a by product of the very warm summer? The central north Atlantic, although still much warmer than average, is much cooler generally that at the same point last year, how this bodes for the weather in this autumn and coming winter is anyone’s guess, but mine would be for a very mild, wet autumn and winter, but don’t quote me on that because I’m no expert😉

UK Daily Temperatures so far in 2023

I have added a new viewer to my 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. climate application to display estimated daily temperatures for the whole 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.. I use as many daily reported maximum and minimum temperatures from 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. stations 03001 to 03950 as I can to calculate a UK mean for all stations below 250 M amslAMSL The height Above Mean Sea Level.. That equates to around 120 observations each day. Nowhere near as accurate as the 1 km x 1 km gridded estimates 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, but good enough for me. As you can see it picks out the two heatwaves that have occurred this year. It does look like my estimates maybe just two high though, because mean temperatures in both July and August were much close to average than this. That’s not really that surprising because its totally dependent on an even spread of site location, but they tend to be further south and coastal sites. I suppose that I could use all available sites, even those on mountains, and adjust their temperatures down to sea level.

Mega SYNOP Meteogram

I updated my Meteogram viewer yesterday which displays hourly 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. observations for any period in a 4×5 grid of charts. Some values are straight from the SYNOP, others are derived. I think you’ll agree, there’s a lot of observational and climate information locked up in each humble SYNOP. I’ve tried to graph all possible data types from the observation, the degree of windchill will require some further work😉

17-18 Sep 2023 | Heavy Rainfall

Global Temperatures 2003-2023

After the triple dip in the 12 month moving average of global temperature anomalies since their peak in 2016, global temperatures are now back on the march upwards once again. Looking back at the last 20 years a simple linear trend on the monthly anomalies reveals that anomalies are rising at the astounding rate close to 0.25°C per decade or 2.5°C per century. You’ll notice that the two charts from the ECMWFECMWF The European Centre for Medium-Range Weather Forecasts is an independent intergovernmental organisation supported by most of the nations of Europe. It is based at three sites: Shinfield Park, Reading, United Kingdom; Bologna, Italy; and Bonn, Germany. It operates one of the largest supercomputer complexes in Europe and the world's largest archive of numerical weather prediction data. in Europe and NASANASA The National Aeronautics and Space Administration is an independent agency of the US federal government responsible for the civil space program, aeronautics research, and space research. & GISSGISS The Goddard Institute for Space Studies is a laboratory in the Earth Sciences Division of NASA's Goddard Space Flight Center affiliated with the Columbia University Earth Institute. in America show similar results.
Again, I’ve spent some time smartening up this monthly view of anomalies that include the usual linear trend and a 12 month moving average overlay.

September 2023 – ENSO

El NiñoEl 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 is anticipated to continue through the Northern Hemisphere winter (with greater than 95% chance through December 2023 -February 2024).

In July, El Niño continued as indicated by above-average SSTSST Sea Surface Temperatures across the equatorial Pacific Ocean. Nearly all of the weekly Niño indices in the central and eastern Pacific were in excess of +1.0°C: Niño-3.4 was +1.1°C, Niño-3 was +1.8°C, and Niño1+2 was +3.4°C. Area-averaged subsurface temperatures anomalies decreased compared to June, but remained positive, in association with anomalous warmth across the equatorial Pacific Ocean. Tropical atmospheric anomalies were also consistent with El Niño. Starting in mid-July, low-level winds were anomalously westerly over the western equatorial Pacific, while anomalous easterlies prevailed over the eastern Pacific. Upper-level wind anomalies were westerly over the eastern Pacific. Convection continued to be enhanced around the International Date Line and was weakly suppressed in the vicinity of Indonesia. The equatorial SOISOI The Southern Oscillation is the atmospheric component of El Niño. This component is an oscillation in surface air pressure between the tropical eastern and the western Pacific Ocean waters. The strength of the Southern Oscillation is measured by the Southern Oscillation Index. The SOI is computed from fluctuations in the surface air pressure difference between Tahiti (in the Pacific) and Darwin, Australia (on the Indian Ocean). and the traditional SOI were both negative. Collectively, the coupled ocean-atmosphere system reflected El Niño.

Courtesy CPC

I have smartened up my ENSOENSO El Niño–Southern Oscillation is an irregular periodic variation in winds and sea surface temperatures over the tropical eastern Pacific Ocean, affecting the climate of much of the tropics and subtropics. The warming phase of the sea temperature is known as El Niño and the cooling phase as La Niña. application a little and downloaded the latest data. The monthly anomaly for August when published (the average of the three months July through to September) will confirm the current El Niño event started in June, but the rules used by 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., if I remember them correctly, are that you need three of those three month averages above +0.5°C before this happens. The ENSO rules and stats are always a bit murky.
Here is another view of the weekly data that my ENSO application also displays.

Heatwaves in Central England 1878-2023

It’s slightly difficult to gauge the number of heatwaves in Central England. One of the reasons for that is the CETCET Central England Temperature series is made up of a composite temperature from three separate sites, the other is that the series extend back so far, 1878 in this case, that choosing a fixed value for the whole of the last 145 years is problematic because of increases due to global warming. My DCET application allows the user to define which threshold to use and it’s length. In the example above the application displays all heatwaves of three consecutive days or longer, with maximum daily temperatures of 25°C or higher. 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 current criteria for heatwaves is 25°C for a large part 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.. Of the three sites that are used to calculate a composite temperature for central England at the moment, one of them Stonyhurst is in the 25°C region, the main one Rothamsted, is in the 28°C region, and the other Pershore, is in the 27°C region. So you could argue I should use the weighted average of the three 27°C but what the hell.
The longest heatwave in Central England lasted for 16 days, from the 23rd of June to the 8th of July 1976. That’s one day longer than the 15 days of 2018 for similar dates. The earliest heatwave in the series back to 1878 if I’ve done my programming correctly was from the three days from the 28th to the 30th of May 1944. The latest heatwave was the three days that started on the 29th of September and lasted to the 1st of October 2011.
I’ve catalogued 145 individual heatwaves in 145 years which is a bit of a coincidence and not a lot of people know that.
The recent record breaking heatwave for September (2023) that’s just finished (and here I’m assuming it finished on the 10th) lasted for seven days from the 4th to the 10th of September, which makes it the joint fifth longest heatwave in the series to date, in fact it equals the seven day heatwave that occurred earlier in the year in June.

Are heatwaves getting more common?

Yes, of course heatwaves are getting more common, CET temperatures have been rising at the rate of 0.254°C per decade for the last 50 years, so they are bound to get more frequent and longer lasting. The chart below gives you an idea of the increase, it displays a bar chart of the annual number of days when daily maximum CET exceeds 25°C. I have added a 10 year centred average to the chart, and also a linear trend from 1878 to 2023. A shorter trend would show a much larger rise than the 0.4 days/decade increase than this trend shows but I am starting to flag and it’s getting near to dinner.

A look back at the Autumn of 1959 [SON]

Autumn 1959
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. & 500 hPahPa A Hectopascal is the SI unit of pressure and identical to the Millibar gph

I can already see a few similarities in the first week of September with the memorable September of 1959. September 1959 had the third longest anticyclonic spell in the whole objective 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. series that began in 1871. The heatwave in the first week of September 2023 looks poised to break a number of CETCET Central England Temperature record maximum temperatures that were set in 1959. In 1959 as well as possible heatwave conditions occurring between the 7th and 12th of September in central England, a second warm spell occurred between the 3rd and 7th of October. It will be interesting to see just how anticyclonic September 2023 proves to be, and if November turns out to be as cyclonic as that of 1959.

Autumn 1959 [SONSON Meteorological Autumn - September, October and November]
Daily Central England Temperatures

September 1884-2022
Ranked Highest Mean Maximum Temperature

1 Comment / September 7, 2023

Autumn, Climate

A look back at the Autumn of 1959 [SON] Read More »

August 2023 – Circulation

It’s easy to see why August 2023 was such an unsettled month across Ireland and 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. with temperatures just below the average when you study the 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. anomalies.

August 2023 – Global temperatures

_{^{August
DIYDIY Do It Yourself Global temperature series
1948-2023}}

Not content with having the warmest July on record, 2023 has now produced the warmest August on record too. Although it’s not quite as warm a month as July was, it easily beat the August of 2016 into second place. The years 2016 and 2023 are neck and neck at the moment for the warmest year on record, but I think there can be little doubt that 2023 could end up being the warmest year even though there are still four months to go.😮
Of course global temperatures could slump in the next four month. At the moment in my DIY series, the global mean daily temperature for the 1st of September 2016 has just overtaken that of the 1st of September 2023 (see graph below) so it’s still going to be a close run thing.

I’ve based this story on reanalysis data that I use in my DIY Global temperature series. It tracks the other series quite faithfully and I have no doubt that in the coming week Copernicus will confirm what I’m guessing at. Well it’s all a bit of a guess anyway.

August 2023 – Temperature anomalies

To say that the estimated global temperature for July made it the warmest on record of any month since 1850, it seems that no one bothered to let August know, and August had no intention of following suit, at least in our corner of the world.

Iceland was noticeably colder than average again.
The record high SSTSST Sea Surface Temperatures kept the North Atlantic ~ 1°C above the LTALTA Long Term Average. This is usually defined as a 30 year period by the WMO..
The intense heatwave in southern France seems to have been cancelled out by an equally cold start to August that no one seemed to notice.