Model Output Discussion - What does April have in store?

[BlueHedgehog074]

1 hour ago, shaky said:

Not the best of 12zs it has to be said for an extension of the heat!ecm at 144 hours the worse of the lot!!deep low to the south west!!!make the most of this between now and tuesday if we go according to ecm!

Does look like the odd case at the moment where some of runs move things further West during their morning updates, and then shift everything back further East during their afternoon and evening updates! 

[I remember Atlantic 252]

7 minutes ago, DiagonalRedLine said:

Does look like the odd case at the moment where some of runs move things further West during their morning updates, and then shift everything back further East during their afternoon and evening updates! 

Aye, well I prefer the morning updates

[shaky]

9 minutes ago, DiagonalRedLine said:

Does look like the odd case at the moment where some of runs move things further West during their morning updates, and then shift everything back further East during their afternoon and evening updates! 

Yup noticed that and also the shift west over the last few days has started on the 18z gfs so the next gfs run should be quite interesting!!

[Frosty.]

Plenty of very summery warmth and sunshine indicated on tonight's Ecm 12z ensemble mean..fantastic easter weather!!

Edited April 18, 2019 by Frosty.

[BlueHedgehog074]

11 minutes ago, I remember Atlantic 252 said:

Aye, well I prefer the morning updates

Same! Prefer having the pattern further West (even tho admittedly some of us could do with some rain). 

[I remember Atlantic 252]

9 minutes ago, DiagonalRedLine said:

Same! Prefer having the pattern further West (even tho admittedly some of us could do with some rain). 

Aye, well the rain can come at night, (here anyway) but never does, fronts always timed for the day, unless thundery plumes

[Frosty.]

To me it's a bit silly worrying about possible breakdowns from next midweek when the models are showing such amazing weather for easter, 23c was recorded today and in the coming days 24,25 or even 26c is likely in places..enjoy it!

[I remember Atlantic 252]

1 minute ago, Frosty. said:

To me it's a bit silly worrying about possible breakdowns from next midweek when the models are showing such amazing weather for easter, 23c was recorded today and in the coming days 24,25 or even 26c is likely in places..enjoy it!

agree frosty, your post is dead right, but to me Easter means nothing, just a normal weekend, but to many going away, great it's summery

[Man With Beard]

A careful study of the ECM ensembles suggests, IMO, a breakdown Weds into Thurs is the favoured option, with Tuesday possibly the peak of the warmth. Subject to change though! 

[ANYWEATHER]

Evening ! A thundery breakdown after the Easter weekend...is the Atlantic coming in or not ? Just a wifff off Brexit here ! 

[knocker]

The 500mb NH profile and the Atlantic surface analysis for midnight and the 0400 UTC chart

Once the early morning mist/haze has cleared a warm sunny day for virtually all areas. Perhaps the sun filtered a tad through Cirrus in some and again cooler along the NE and eastern coastal regions. By late afternoon some thicker cloud encroaching the far north west as fronts associated with the low east of Greenland approach

Tonight will be clear in most areas with a nip in the air in eastern regions with the odd fog patch forming. The cloud continuing to thicken and spread in the north west

Once any fog clears a dry and very warm day for most areas on Saturday (including now the east coast) but the cloud continues to thicken and push south east in the north west and there may well be some patchy rain/drizzle. And consequently temps down in this area. And perhaps the sunshine filtered a tad south of this courtesy of Cirrus associated with the frontal system now weakening against the block

Another very warm day on Sunday but cloudier and becoming quite windy over Scotland as the upper trough to the north west becomes more organized which, along with the low over Iberia, starts taking on some significance

By Monday the upper trough to the north west has started to deconstruct and phase with the trough to the south as the Atlantic subtropical high amplifies in the west. The waving surface fronts associated with this trail south just to the west of N. Ireland and western Scotland thus still cloudy here with patchy rain but elsewhere another warm day, albeit cooler once again along eastern coastal regions

And by Tuesday there is a new low close to Coruna and convective activity is starting to move north into the south west on what is generally a day when the temps will be down a bit from the weekend. This especially applies once again to eastern coastal regions.

 

Edited April 19, 2019 by knocker

[knocker]

As can be seen on the last voracity chart above there is now a conduit to the north west and by midday Wednesday there is a complex trough west of Ireland running south, with surface fronts aligned down Ireland, and more general convective activity over England and Wales. Thursday and Friday becoming more unsettled as the aforementioned front(s) traverse the country and temps return to around normal. There is still much uncertainty about next week so caution strongly advised

The NH 500mb profile for midnight Thursday gives an overview of all of this

Edited April 19, 2019 by knocker

[knocker]

The ecm differs in detail but it too is moving into a more mobile westerly pattern next week

[knocker]

The model output over the last few days certainly brings to mind the dictum of my old friend Sammy Rochevsky

"The reliability of the models is inversely proportional to the length of time from day zero. Ergo it is logical, when analyzing the outputs, to start at day zero and work out, rather than day ten and work in"

Another cracking morning so off to see Sidney

[Summer Sun]

Looking at 00z UKMO it might not be until mid next week that we see some fairly widespread rain. It's looking like a warm and dry Easter weekend away from Scotland and parts of NI/ROI

[BlueHedgehog074]

An example at 216 hours, but both the 00Z GFS and 00Z GEM show High Pressure building back over the U.K towards next weekend. 

Both clearly not liking the ECMWF this morning and are joining forces against it.

(ECMWF at 216 hours)

The trough conquers the UK! Something the warm and High Pressure enthusiasts won’t be pleased about! But could provide a lot of convective, showery, weather.

The build of Pressure, though, could be a bit stronger on the GEM, but still pretty much shaking hands with the GFS. 

Expect more changes towards the end of next week. And even, in some ways, the earlier part of that week. How ever much the trough goes on a rampage over the U.K (doesn’t look like the models remembered their Westward adjustment of the pattern this morning ), could resultantly affect what happens after. Can the Low Pressure lift away quickly enough (with some of it getting cut of to our South) and allow High Pressure to come back to the rescue? Or will the sneaky Low(s) get stuck over us like glue? 

Personally hope for the former. While as I said, things will keep changing, it’s tempting to gather up some bomb-ombs from Mario Kart 8 Deluxe’s item boxes and toss them at that Low on the ECMWF towards the end of it’s run! 

It’s quite likely Low Pressure from the West in the Atlantic will pay some kind of visit over the U.K next week. This especially so over Western areas with some rain and thundery showers about. Plus, there is some warm, bright and generally dry weather to look forward to over this Easter weekend, where models show High Pressure being mostly in control (albeit with the threat of soggy weather towards Western areas later on into this weekend). ??

Edited April 19, 2019 by DiagonalRedLine
(correcting odd mistake)

[Methuselah]

And, after a stonking BH weekend, we may even see some of the much-needed 'wet stuff', come Wednesday!

 

[Methuselah]

I'd be happy with something along the lines of how the 06Z ends: some rain and reasonable temperatures? If it's going to rain, let's get it over with before summer proper arrives?

 

[Frosty.]

There's plenty more warmth to come which lasts well into next week according to the Ecm 00z ensemble mean, even signs that the azores ridge could be building in later!

[Polar Maritime]

NetWx take on Wednesday next week, Could be some thundery potential for the South to..

 

[Methuselah]

And, as we get into Friday, the FV3 has us within a more generally unsettled regime, but still with reasonable temperatures:

 

[chrisbell-nottheweatherman]

Is the FV3 the uprated GFS?  Any idea as to whether it's less-prone to the old GFS biases?

[knocker]

Grand sat image

[Frosty.]

32 minutes ago, chrisbell-nottheweatherman said:

Is the FV3 the uprated GFS?  Any idea as to whether it's less-prone to the old GFS biases?

It has a bigger cold bias than me!!..looking forward to what it shows in summer.

[Methuselah]

And, as we move on down the line (thank you, Roy Orbison) the FV3 produces a watered-down version of its obligatory 'Arctic Blast':

What's the chance of this one verifying!

 

Edited April 19, 2019 by Ed Stone