[Moans, ramps and banter]

What a bust!

 

[Storms and Convective discussion - May 2024]

London direct hit! Best May thunderstorms since 2018 although not on that level, at height was flashing about every 10 seconds, surprising amount of thunder too perhaps it wasn’t entirely elevated. Very heavy rain too. I can’t say I recall seeing a thunderstorm Thames streamer before - certainly a novel event. 

[May 2024 C.E.T. and EWP forecast contests]

12.8c and 60mm thanks difficult one, seeing potential for something colder mid month which could make a good dent but unsure about extent and longevity. 

[Model Output Discussion - Spring Has Sprung]

5 minutes ago, Sherry said:

There was no cross model agreement for bank holiday weekend?

Well actually GFS was initially more the odd one and it proved right. There was decent representation for a warmer/settled long weekend outcome in EPS, it wasn’t just coming from det.

It has gone from this to this for Saturday 

[Model Output Discussion - Spring Has Sprung]

ECM used to be quite convincingly best performing model unsure it is anymore..

From this to that quite shocking , still optimism for a noticeable improvement next week but it’s never easy.

[Moans, ramps and banter]

Heathrow temp/rainfall data from January 1948

https://www.metoffice.gov.uk/pub/data/weather/uk/climate/stationdata/heathrowdata.txt
 

sunshine began being recorded in January 1957 with Campbell Stokes recorder was used until October 2005 where it was changed to automatic Kipp & Zonen sensor.

[Moans, ramps and banter]

5 hours ago, B87 said:

wonder if we will get a 3rd 200% rainfall month in a row, in the last few days of April?

Now up to 69.0mm for the month, ridiculous.

2024 will finish far wetter than average, calling it now. There is no realistic way we will only get another 300mm all year.

I did some calculations..

 

[SE, London and East Anglia Weather Discussion - Dec 2023 on]

Third wettest day of year here 17mm still raining. A really miserable spring so far and we thought 2023 was bad.

[Spring 2024]

4 hours ago, raz.org.rain said:

Part of me wonders if this run of SSWs is related to El Niño conditions and warmth being shunted into the Arctic. Considering everyone keeps banging on about how global temps will cool down with La Niña, presumably this will include the Arctic. Less anomalous warmth in the Arctic would drastically reduce the possibility of SSWs if I understand right.

No this is first El Niño winter since 2018/19… La Niña has been dominant. The Arctic 80N+ hasn’t been abnormally warm either in 2024 so far. There isn’t a good correlation on poles, tenuous at best. 

[Moans, ramps and banter]

Fallen here to 7,5C here in central ish London with cold light rain this is really quite dire. Heating on.

[Moans, ramps and banter]

7 hours ago, richie3846 said:

I've saved a screenshot shot of B87's calculation table for future reference. Very useful. I'm thinking a lot of the ongoing discussions about sunshine over the years, may have been unintentionally misleading and pessimistic because of this discrepancy. I'd say this topic needs bringing to the forefront from time to time, to remind people of the adjustments, and to check their sources of information for raw or adjusted data, where that is possible. 

It might not be relevant or applicable to other stations the Heathrow sun recorder was changed in late 2005. From Campbell Stokes recorder to automatic Kipp & Zonen sensor, it’s believed to marginally record less sun. 

[April 2024 C.E.T. and EWP contests]

Today looks coolest day in CET area not in north of it though, chilly night and daytime temps looking more suppressed than expected.

E.g. Rothamsted 0.7C low… 10.1C high… 5.4

[Moans, ramps and banter]

On course to be dullest April in 26 years (1998) in London. The east has definitely faired much worse than west. Miserable, nondescript month really. 

[Moans, ramps and banter]

35 minutes ago, raz.org.rain said:

have gone as far as to suggest that there'll be no overall cooling post El Niño, which would be the first time that has happened.

These people should be ignored.

[Model Output Discussion - Spring Has Sprung]

Horror show pattern into early May on tonight’s GFS 18z…. takes one back to 2007-2012. The N Atlantic/Greenland blocking is difficult to shake off in spring with polar vortex out the picture. 

[Moans, ramps and banter]

25 minutes ago, danm said:

Low daytime maximas such as this are not that uncommon in April.

They are much more notable later in month that’s the point. Using the point of 2018 an exceptional spring certainly demonstrates something. If we see a daily record with over half a century of data, it’s noteworthy at the very least. 

[Moans, ramps and banter]

13 minutes ago, danm said:

Low daytime maximas such as this are not that uncommon in April. It's significantly below average, but at a time of year when wild swings in weather is common, extremes of both cold and warm can happen. 

Just done for Heathrow, preliminary high of 9C it’s tied lowest max on record for date with 1973. This is exceptional. 

 

[Moans, ramps and banter]

26 minutes ago, richie3846 said:

No it's not exceptional. The majority of Aprils have days in single figures. I just browsed weather data for Brize Norton and the vast majority of years over the last 15, have days below 10c. This is just a normal April day even if people don't like it, it's normal had happens most years I'm afraid. Let's not get preferences get in the way of facts. 

It’s April 22nd…. The facts are your wrong. 

[Spring 2024]

 

[Model Output Discussion - Spring Has Sprung]

10 hours ago, Scorcher said:

LetItSnow! I'm not denying it's going to be chilly but one poster in particular is keen to emphasise how exceptionally bad this is going to be- so I stand by my hyperbole comment.

If you’re talking to me at least @ me thanks. In what way I have done that? All I’m saying temperatures are indicated to be well below average for late April, no one has mention snow and freezing temperatures and what can be expected at this time of year. You said about me being antagonistic, I think you should look at yourself, all you do is purposely try to undermine messaging, if anything cool is mentioned, it’s a repeated pattern from you. It’s as if it upsets you personally, I find it very odd it is just the weather. 

[Model Output Discussion - Spring Has Sprung]

Even this weekend has downgraded, it looks rather cold for most as NE’ly is introduced. Warm in west of Ireland closest to ridge. 

[Model Output Discussion - Spring Has Sprung]

2 minutes ago, Frigid said:

A remarkable switch to something cooler, this would've been a notable cold spell in winter. I wonder what triggered this response..

Still seeing drips of SSW which occurred earlier in March this could be what’s responsible, it was a significant event so of course has potential for extended influence. I don’t believe it’s result of MJO that’s been in COD. Perhaps weakening El Niño also a factor nothing we could get on side during winter remained strong.

 

[Model Output Discussion - Spring Has Sprung]

“Slightly below normal” involves 5C even 6C below average T850s. A long time since I’ve seen such a deviation below.

[Model Output Discussion - Spring Has Sprung]

25 minutes ago, WYorksWeather said:

It all depends on the averaging used

Well the data suggest otherwise also signalled below on 1961-1990, below is Birmingham next week looks even cooler than this week, you must also consider the average for further in April is warmer, so using overall mean is not wise. 

[Model Output Discussion - Spring Has Sprung]

4 hours ago, Frigid said:

Mild days in the mid to high teens likely.

It seems some are in denial. The mean for Manchester has highs barely in double figures for most part. It’s certainly a cool outlook with winds frequently coming from northerly direction with cool air aloft. A bit milder this weekend with high covering UK briefly, then it looks to re-centre further NW. it’s a very poor outlook if you’re looking for warmth. If only if it was winter comes to mind.