Blessed Weather

Yes, it certainly does look wet under that cold front as it slowly crawls eastward. There's not been a lot of progress over the last two hours and whilst the squall line appears to be less potent, the front seems to be pepping up to give a broader area of heavy rain. 19.30 21.30

Nice squall line crossing the Region this evening: 19.30:

As a result of ongoing issues this thread is now locked. Sadly – despite team requests and the message at the top of every page - there have been too many posts being made in here that are either intolerant or goading those of a different preference. In due course the team will re-launch the clubs but in the Groups area of the forum where membership will be subject to approval and there will be a zero tolerance approach to further offences.

As a result of ongoing issues this thread is now locked. Sadly – despite team requests and the message at the top of every page - there are too many posts being made in here that are either intolerant or goading those of a different preference. In due course the team will re-launch the clubs but in the Groups area of the forum where membership will be subject to approval and there will be a zero tolerance approach to further offences.

For the record, some info on the rainfall from the overnight storms in East Anglia, courtesy of Dan Holley, Weatherquest: Heavy rain and thunderstorms affected many parts of the region overnight, with the greatest accumulations in a corridor from London to Cambridgeshire and west Norfolk — where some gauges recorded 30-40mm. Bedford (Thurleigh) recorded a wind gust of 46mph at 02:04. Source: https://x.com/danholley_/status/1703661987543068702?s=20

Nice rainbow earlier this evening as a heavy shower moved away east. Even a faint double rainbow showing:

Good questions. It seems there is indeed a relationship between AAM and MJO. A few snippets with links to the scientific papers: AAM is useful as an index of the large scale zonal flow since it is highly correlated with independent length-of-day measurements and with phenomena such as the QBO, ENSO, the MJO....... CDC scientists have examined several aspects of AAM variability, including: the link to MJO tropical convection..... Source: https://psl.noaa.gov/psd1/review/Chap04/sec3_body.html The first part of this study examines the driving mechanisms of the equatorial intraseasonal relative atmospheric angular momentum (AAM) and its dynamical relationship to the upper-tropospheric zonal wind over the Western Hemisphere (WH) during the convective initiation of the Madden–Julian Oscillation (MJO) over the Indian Ocean...... The second part of the study investigates the influence of the equatorial intraseasonal AAM state on the subsequent development of initiating MJO convection over the Indian Ocean. In the presence of the WH upper-tropospheric easterly wind, MJO convection tends to develop a stronger enhanced convective envelope when the initiation occurs during the negative intraseasonal AAM state...... Source: The intraseasonal atmospheric angular momentum associated with MJO convective initiations The onset of the significant MJO event was immediately followed by a period of above-average Earth-relative atmospheric angular momentum (AAM), subsequent breakdown of a strong zonally oriented north-Pacific jet stream...... Source: https://www.nature.com/articles/s41612-022-00263-5

Having run through the radar for overnight I'm impressed with the number of storms around. Unfortunately for me they seemed to skirt around my location - but hey ho! Here's how it looked at 00.10, 01.10 and 02.10 this morning:

Aren't those charts in km/h? Converted to mp/h would mean a peak gust of 81 mp/h which, yes, is windy but more in line with typical UK gales?

Interesting to see that at 23C the coastal strip of Kent was as hot as Central London at 10 pm last night. The very high temps in France yesterday meant it was still 27C in parts of Northern France at 10 pm, and with Kent being just a short hop across the Channel, with the gentle S/SE'ly breeze you were basically 'enjoying' imported heat from France.

The September 2023 hot spell continues with many locations in East Anglia having now experienced 7 heatwave days. Once again thanks to Dan Holley, Weatherquest, for the following max temp chart and stats for Sunday, 10th Sept: Cambridge NIAB was the hottest place in the UK on Sunday, peaking at 32.5°C. Many sites now on 7 heatwave days — even Weybourne finally joined in! 32.3°C is a new Sept record at Writtle (since 1959). Ditto 32.4°C at Brooms Barn (since 1964). Source: X danholley_

Step forward Cavendish, Suffolk, as the hottest location in the UK today. I've recorded the fact in the Regional Stats thread:

The hottest location in the UK today, Friday 8th Sept 2023, was Cavendish in Suffolk. This from Dan Holley, Weatherquest: Cavendish was the hottest place in the UK on Friday, reaching 30.9°C — a new September record at this site (records back to 1977). We've now recorded 3 consecutive September days ≥30°C in the region [East Anglia], equalling 2016 and 1906. Source: X @danholley_

East Anglia max temps today (6th) courtesy of Dan Holley, Weatherquest: Writtle was the warmest place in the [EA] region on Wednesday peaking at 30.8°C. Many sites have now recorded an official heatwave The north Norfolk coast was plagued by low cloud/fog, with Weybourne and Cromer recording their highest temp at 9-10am! Source: X @danholley_

The hottest September temp... The all-time record for September of 35.6C (96.1F) was set in 1906, in Bawtry, South Yorkshire. Source: BBC News Certainly impressive to be seeing the 20C 850hPa isotherm over us in September. Probably just as well this isn't June with longer daylight (sunshine) hours and stronger sun. Looking at the Sat24 satellite sequence for the last hour shows the early morning murk and low cloud the Captain mentions above is shrinking all the while. The sun should appear in the affected areas soon. The latest image at 09.45:

August 2023 The month overall turned out to be pretty close to the 1991-2020 climate average for the Region (the period now used by the Met Office). Certainly a better month than the wet July. A few exceptions were some areas near the South Coast that saw slightly less sunshine, and a very notable wet area near the coast of East Anglia - but this was caused by a thunderstorm on the 18th of the month. Some stats for East Anglia, courtesy of Dan Holley at Weatherquest, Norwich: Near-average temperatures (-0.2°C) Slightly drier than average (93%) Near-average sunshine (103%) Wattisham recorded 112mm (186% of its average rainfall). Meanwhile, Cardington received just 35mm (60% of average). This tweet from Dan highlighted an interesting fact about Summer 2023: Some rather meaningless trivia for a Sunday afternoon (3rd Sept), but at 1028 hPa today most observation stations in the region have recorded their highest pressure since 31st May — such was the absence of high pressure through most of the summer... Source: X danholley_

If I may...... but as someone who has lived through all the summers during the period 1961-1990 I thought I would post this summer's anomalies versus the Met Office records for that period. Sunshine duration anomalies for each of the 3 months compared with that period. Not bad at all for the eastern half of the country; either average or above average sunshine amounts: And next the mean temperature anomalies. Not bad at all. Average or above average for the whole of the country for each of the summer months. Seems to me that the Met Office habit of continually moving the goalpost so that current seasons are compared with more recent years (which we all know are being impacted by global warming) is maybe raising expectations for weather that never used to be the norm? Just a personal opinion.

Welcome to the forum GB. I see what you mean about the cloud looking rather brown/orange on the zoom.earth image. I'm wondering if there's some contamination from the Canadian forest fires? I can't find the right ECM chart atm but I'm sure there's output somewhere that shows the spread of smoke polution around the globe. (Maybe someone can help please?). In the meantime I've used ECM CO2 concentration as a proxy and that does suggest a trail leading back in that direction. Anyway, just a thought and I might be barking up the wrong tree! Sources: https://zoom.earth/ https://charts.ecmwf.int/products/carbon-dioxide-forecasts?base_time=202308280000&layer_name=composition_co2_totalcolumn&projection=classical_north_atlantic&valid_time=202308280900

Just a quick post about the severe weather that's hitting the Mediterranean countries, starting yesterday (Sun 27th Aug) and set to continue for the next few days. In summary the Azores High is positioned far enough west to allow a southerly plunge and significant kink to form in the meandering Jet Stream which seems to bear all the hallmarks of a Rossby Wave Break. The resultant cool northerly flow - in particular the Mistral wind funnelling down the Rhone Valley of France - has interacted with the currently very warm waters of the Med to produce an intense area of low pressure with strong winds and heavy rain. Jet Stream and 500hPa pressure anomaly from 08.00 Sunday to 20.00 Monday: The animation for Potential Vorticity at 1.5PVU high in the atmosphere also indicating a Rossby Wave Break. This sequence for the same time frame: The low pressure just hitting the west coast of Italy by 14.00 on Monday: Current Mediterranean SSTs at 28C, which have hit an all-time high this summer: Source: https://www.surf-forecast.com/current-maps/United-Kingdom/sea-surface-temperatures And finally some related interesting news articles: Mediterranean Sea breaks new heat record: What does this mean for weather in Europe? Extreme weather across Europe could extend into autumn spurred by record-high sea temperatures. Heavy storms hit southern Europe causing huge disruption Strong winds and heavy rains have hit Spain and Italy causing widespread flooding and major disruption. The weather is part of a violent storm which broke out on Sunday morning, blowing down numerous trees, causing flash flooding and damaging a bullring in the town of Felanitx. Spain Slammed With Strong Winds In Mediterranean Storm Strong winds and heavy rains slammed Spain on its Mediterranean coast on Sunday, including the touristic Balearic archipelago, causing serious damage and flight disruptions. Gusts of up to 120 kilometres per hour (75 miles per hour), downpours and hail hit the Balearic islands as well as Catalonia and Valencia on mainland Spain, which were all under a high-risk warning by the national meteorological agency Aemet. P&O Britannia cruise ship crashes during Mallorca storms A cruise ship broke free from moorings and collided with a freight vessel during a storm in Mallorca, Spain. Edit: Just to add the very heavy rainfall associated with the above system. A 2021 research paper shows that Rossby wave breaking is associated with >90 % of extreme precipitation events over the Mediterranean. Cumulative precip to Sun to Tues 29Aug 20.00:

I hope the thread goes well KW - it has the potential to be an extremely interesting topic. As we discussed, it provides somewhere to discuss model output and teleconnections from a global perspective, with analysis into the various interconnected upstream and downstream drivers and impacts that result in 'weather' anywhere around the world. I'll certainly try to contribute from time-to-time. Btw, love the animated chart of African Easterly Waves moving out into the Atlantic - they can be a rich source of major Atlantic Hurricanes in a typical year as they go on to develop over the warm waters.

Great day for towering cumulus clouds. Always a wonderful spectacle.

The Netweather Extra V8 radar comes with a 'current weather' overlay feature which includes Humidity readings at official met office stations in the past hour or two (you click on the reading for the update time). Here's a screen grab from the radar at 06.55 this morning: Alternatively there are the Meteociel Humidity charts and they offer an archive feature so you can check back on previous dates. Here's the screen grab at 06.00 this morning and note the same readings as the Netweather radar:

That's frustrating. The electrics kicked off after passing my location (the triangle circled). Radar 08.00