Model Output Discussion - Spring Has Sprung

[Djdazzle]

No way that anyone can predict a washout next week - yes, low pressure will be close by but it’s way too early to put any detail on things.

This time last week, some on here were writing the whole of the bank holiday off. It turned out that down here, Saturday and Sunday were fairly nice days.

 

[LetItSnow!]

 Djdazzle See latest post as I think I came at it as unbiased as possible. I don't see a washout everywhere per se, I do think we could be facing a period of torrential downpours and large totals of rain in some places, but I don't forsee days of gloom. Low pressure systems often get typecast as gloomy when, depending on the source of the air and fronts etc, can often bring sunny spells and often thunder.

[northwestsnow]

Glorious EC det by day 10..

Let's see how it sits ..

[Scorcher]

 MP-R It's not common away from the South East before mid month. Yes it does happen in some years but a small minority.

[Addicks Fan 1981]

 northwestsnow safe to say tonight that GEM is very much the bad guy of the models with not much ridging at all.   

[WYorksWeather]

Another slight downgrade in temperatures for Sunday on tonight's UKV. Still looks like a good chance of 25C on Saturday and/or Sunday though. But now somewhat less notable than if we had seen high twenties.

Still a definite warm to locally very warm feel to things over the next few days. By Monday, cooler weather moves in from the west but some eastern areas may yet scrape out an additional warm day.

Beyond early next week, currently the ECM meteograms are showing a gradual fall in temperatures to just above the 20-year average by around Tuesday or Wednesday, with predominantly south-westerly to southerly winds being favoured along with significant amounts of rain.

Beyond Wednesday at this stage is far too uncertain, the ECM wind plume just loses the plot altogether and winds could be coming in from virtually any direction. This is likely due to the uncertainty in positioning of the trough.

Summary

In short whilst a wetter and somewhat cooler start to next week is likely, temperatures are still forecast at this stage to be near or slightly above average. Beyond Wednesday I think is still too far ahead at this stage. For the second half of next week options include a quick return to high pressure or a more prolonged unsettled period. At this stage it's impossible to call, frankly.

[SunSean]

Is it just me or is the word "trough" one of the ugliest words in the English dictionary, up there with the likes of "moist" & "mucus" lol.

If I see another post with "UK trough" in it, I'm gonna scream!

[WYorksWeather]

 SunSean Would 'an area of below average barometric pressure' be an acceptable euphemism?

(note - feel free to tag me in moans if you want to discuss further, I don't want to get hit with a hammer for derailing the thread)

[WYorksWeather]

To bring things back to model output - again my usual update on sea surface temperatures.

We start with the absolute values for days 0, 5, 10 and 15.

A dramatic rise in SSTs clearly visible over the next two weeks. But of course this only tells a limited story by itself in the context of seasonal changes.

The anomaly maps for days 0, 5, 10 and 15 are shown below.

Pretty clear to see what is going on here. The trend from a week or so ago to decrease the anomaly around day 10 (now closer to day 5) and then re-establish has been dropped. By day 15 the ECM has us in a pretty extraordinary situation. SSTs 1-2C above average near the Azores. Near the UK, SSTs are almost universally 2C or more above average, and in some spots the anomaly exceeds 4C.

Of course that is a fair way off being two weeks away, but if it did happen, it would certainly act to boost temperatures, particularly overnight.

[joggs]

I'm sure it won't be a washout. There'll be some downpours and sunny spells in between at times. Could feel pleasant at times but cool under prolonged rain.

[Daniel*]

There is not escaping trough influence into next week. We find ourselves wedged between two areas of high pressure in N Atlantic and Scandi… low pressure gets stuck in mud over UK. A lot of rain could fall in some places. That is reality.

 

[Addicks Fan 1981]

Have to say this CPC NOAA 8-14 day chart didn't fill me with much joy.  We need the red shaded areas over us, not an undercutting low feature.  

Edited May 8 by Addicks Fan 1981

[Addicks Fan 1981]

 Daniel* one bit of crumb of comfort I saw across the sites was a more coherent MJO being progged in two weeks time out of the COD area and through the maritimes I think.  Think next week is definitely a feel of our weather to the fall out of the stratosphere warmings we have had.    

[MP-R]

 Scorcher I live in the west and it’s not uncommon.

[Scorcher]

 MP-R Would like to seem some stats on that- I was referring to 25C+ specifically before middle of May. Here 2016 and 2018 managed it in the last decade and we often do just as well as areas further south at this time of year. That is a minority of years.

[Notty]

 SunSean phlegm

[*Stormforce~beka*]

 WYorksWeather This did make me LOL!

[summer blizzard]

 Addicks Fan 1981 Tropics will be dead towards months end.

 

[Addicks Fan 1981]

Possibility of a ridge for next weekend if the ECM 0Z is to be believed in ten days time.  

[Alderc 2.0]

Not a lot going on in here this morning - not even Sunday is pinned down yet and solutions for next weeks trough vary drastically. ECM, GEM and GFS appear keen on a rebuild of pressure by the following weekend however positioning very questionable at this range. 

[Addicks Fan 1981]

 Alderc 2.0 depends on the orientation and the jet stream obviously.   We need the jet stream in the right place without any dipping really.   I did also observe that the weather in the tropics should be on our side soon as well.  

[Addicks Fan 1981]

According to the GFS 0Z when we get the HP orientated weather it will last for a while.   

[Pauski]

32 minutes ago, Addicks Fan 1981 said:

Possibility of a ridge for next weekend if the ECM 0Z is to be believed in ten days time.  

Looks like high pressure in Scandinavia/Finland for a while and with that no rain in sight. 

Also not as cold as the monthly forecast says.

I hope that things will turn into 2010 style and high pressure will settle in northern Russia later in the summer.

[Rain All Night]

On 08/05/2024 at 11:41, Rain All Night said:

0z ensemble means, out to Thu 23 May (day 15)

There remains no meaningful signal beyond Friday 17th May, so everything remains on the table for the following weekend.

0z deterministic runs, on Wed 15 May (day 7)

There's no denying it, this is unfortunate. At least we've got this week, including a fabulous-looking Friday and Saturday, and the hope that better days could return again from Saturday 18th May onwards.

Hopefully everyone is quiet because you're all out enjoying the lovely weather we have now 

0z ensemble means, out to Fri 24 May (day 15)

From Saturday 18th onwards, you can see the real potential for warmth to come up from the southwest, and you can also see the danger lurking up near Iceland. It's impossible to say any more than that at this stage, but the foundations for hope are certainly there.

0z deterministic runs, on Thu 16 May (day 7)

Hopefully from Thursday onwards, the slackening surface pressure will create more opportunities for dry and sunny interludes. So it oughtn't be the case that the whole working week needs to be considered ruined.

Edited May 9 by Rain All Night

[ChannelThunder]

Models really struggling with this low at the start of next week. I like the UKMO version which brings up a modified plume and starts to pump some good uppers into the east, but ECM and GFS look more likely with a more typical solution of the low either filling on our shores or allowing a maritime flow in.

Edited May 9 by ChannelThunder