Spring 2024

[WYorksWeather]

I think more generally, any attempt to use analogues suffers from two key flaws. One is that the major circulation patterns just aren't the be-all and end-all. In short, there are different variations of El Nino (west based, central, or eastern), and also local factors simply overpowering the global patterns. Nobody could have confidently predicted that a promising winter 2023/24 from a teleconnections point of view would turn into a total bust on the basis that we have near record cold at times in Scandinavia, but an amplified Azores high moving north-east and becoming an Iberian high would be sufficient to just derail the entire winter, and never really consistently let up at any point.

Same is true with regards to the coming summer - we all enjoy predicting, but at the end of the day, if we get a setup with serious heat over southern Europe and the Azores high keeps ridging in - it'll be a long, hot and dry summer. Alternatively, if we get a massive block setting up over Greenland and staying there for the whole summer, it'll probably be wet, changeable and somewhat chilly, regardless of whatever else might be going on around the world. Weather is local as well as global after all.

[damianslaw]

 kold weather 2018 spring was one of two halves, first half cold and wet, second half warm and very dry, not one to class as wet overall. 

Edited March 29 by damianslaw

[Weather Enthusiast91]

 damianslaw I have a feeling that this is how spring 2024 will turn out. 

 

 

[kold weather]

 damianslaw I mean it's the 16th wettest spring ever recorded. I grant you it was very much of two halves but its an undeniably wet spring overall on the basis of the ewp over the 3 spring months.

Even May 18 was not *that* dry, ended up at 81% of average. Dry but not excessively so as an average.

The summer is clearly a different story!

Edited March 29 by kold weather

[LetItSnow!]

 damianslaw  kold weather  I agree with that 100% actually. It's easy to forget how unsettled March and April were at times and even May 2018 wasn't excessively dry across parts of England from just how thundery the month was in the latter half. It makes sense that in the north that wouldn't seem so obvious.

  

Edited March 30 by LetItSnow!

[WYorksWeather]

 LetItSnow! Here's what the CFSv2 has for May at the moment.

Warm and wet being th eorder of the day, with heights away to our east. We have lost the negative height anomaly over the UK and to our west, so again possibly a warm and thundery kind of pattern - actually looks somewhat similar to the May 2018 actuals in terms of the rainfall distribution, but a fair bit wetter overall.

[LetItSnow!]

 WYorksWeather Though I don't believe in the CFS forecasts, such a pattern isn't totally cuckoo as you could have a trough (not shown on the map but likely to be there) to the west/southwest and persistantly high pressure to the east giving a mean southerly quadrant flow with a lot of mild south-westerly unsettled weather with unexceptional daytime highs but warm lows and then have just one decently very warm spell and you've easily got a very warm May on your hands. Indeed I feel like a warm, wet May is more common to achieve than a warm, wet April.

[WYorksWeather]

 LetItSnow! I don't have particularly high confidence in them either. They are a little better than a climatological forecast, but that is about all.

I think the stats before tend to be that the skill level of forecasts drops to only a little above climatology or analogue based forecasts by about 2-3 weeks lead time, and then remains slightly better out to 2-3 months, after which forecast skill is negligible.

[raz.org.rain]

 WYorksWeather  LetItSnow! was going through some old tweets and spotted this one from the 10th of January 

 

[LetItSnow!]

 raz.org.rain I do remember that! And admittedly my hopes for a cold winter lead me to being more open to the idea. There were so many drivers that pointed towards it to be fair that that is what grew my belief that it could have gone cold rather than any long range models. Indeed when we first turned cold in early January and the models were playing with extending it, I thought perhaps we could be in for a 1985/1986 lite type winter where it starts very mild but gets progressively colder, but by early February I knew it was a bust. Even the Met Office played into it which I found unusual. Because January had been very changeable (I still think their review is odd and paints the month as extreme for its contrasts is rather strange) they were talking about how they thought February would see more of the same. They definitely were more open to cold in their longer range forecasts this past season but it all came to zilch.

[Weather Enthusiast91]

 raz.org.rain Whatever they predict, you can expect the exact opposite to happen. 

[WYorksWeather]

Yep, certainly not vouching for the reliability of CFSv2 or EC46 or any other long range model. But given that other methods like analogues were also a bust for winter 2023/24, I definitely still think there's some value in posting them, but just best to treat them as low confidence.

[cheese]

 WYorksWeather I’ll take warm and wet if it’s of the thundery variety with brief downpours instead of prolonged frontal rain. 

[raz.org.rain]

Weren't the models suggesting that this Easter weekend would be a chilly washout? Today has been sunny and mild for most and tomorrow looks to be the same.

[WYorksWeather]

In relation to a query on the CET thread, I went ahead and did some analysis looking at the frost frequency in spring for the CET region. Records start in 1878. For each chart, the lines are 30-year trailing averages (e.g. 1950 = 1921-1950, 2010 = 1981-2010, etc.), so the first average is in 1907, for 1878-1907.

The green line is the number of days in the month with no frost, the light blue with a ground frost (I defined this as <=4C but >0C), and dark blue with an air frost (<= 0C).

I've forced the scale to stay the same, so the differences can clearly be seen between the spring months.

So, without further ado, here are the charts for March, April and May (left to right):

For some noteworthy monthly statistics for individual years, we have the following.

Frosty

March: Most total frosts (1883, 1885, 1900, 1919, 2013, all with 30 total)

April: Most total frosts (1887, 5 air frosts, 22 ground frosts), most air frosts (1917, with 14), honourable mention (2021, 10 air frosts, 17 ground frosts)

May: Most total frosts (1996, 1 air frost, 13 ground frosts), most air frosts (1891, 1941, both with 3)

Frostless

March: 1 air frost, 6 ground frosts for least total frosts (1957)

April: 3 ground frosts and 0 air frosts (1961, 2011)

May: 12 frostless (1889, 1893, 1919, 1952, 1964, 1970, 1978, 1985, 1999, 2007, 2022, 2023)

 

 

[WYorksWeather]

 raz.org.rain At very long range, yes. The whole Easter period looked poor. But for at least the last few days, it has looked like Saturday and Sunday would be the most useable days, and then deteriorating on Monday.

I think we probably have to hope for similar downgrades in the wet weather for the next 10 days - some of the recent runs are just ridiculously poor, months' worth of rainfall in the first 10 days type poor for early April. Hopefully we can maybe get an upgrade from diabolical to poor with one or two better days, at the very minimum.

If the first 10 days of April really are as bad as some of the model output is suggesting, and are then not followed by a dry period, we are probably looking at serious flooding.

[SunnyG]

 WYorksWeather The Meto video I watched had three model outputs: one was theirs, one was Euro and the other French. The Met guy said he thought theirs (which was more negative, with more rain and colder temps) was less likely than the more positive Euro one. The question surely is: why then did Meto keep the model he thought less likely?

[Azazel]

What a horrifying outlook. 

[TwisterGirl81]

I think if we have a wet April and May I will go doolally seriously, please no, we have had more than our fair share of rain, I honestly can’t believe how many wet months we’ve had in succession without adding 2 more to it. The only thing that’s getting me through is the hope of a warm sunny second half of spring and a warm sunny sunny.

I’m not sure I believe in cloud seeding but there’s a few countries that dislike the uk thanks to this toxic government that are capable…..would make sense

[raz.org.rain]

 SunnyG it wouldn't be a good look if a meto presenter neglected to discuss the meto forecast, even if they know it's the least likely.

[danm]

28 minutes ago, TwisterGirl81 said:

think if we have a wet April and May I will go doolally

We are nailed on for a wet first 10 days or so of April. Anything beyond that I don’t think we can say with any confidence. It’s tough at the moment but there’s nothing to suggest we can’t get a flip to warm, sunny and dry as we push into late April and May. The flip happened very suddenly in April 2018 after a very cold March and a very cool and wet start to April that year. 

[SunnyG]

 raz.org.rain It's a worse look to admit that theirs isn't the most likely forecast, imho

[SunnyG]

 danm The flip happened today, which was supposed to be cloudy and 13-14c, while in fact was sunny and warm (at least in London). I don't trust anything beyond 24 hours.

[raz.org.rain]

Despite the awful opening to April it supposedly looks to be a warm first half by CET standards. It'll be wet but probably mild, which is better than the previously forecasted wet and cold. April CET looking to potentially be +10°c.

[danm]

 SunnyG the forecast was for sunny spells and 15c today.