Model Output Discussion - Spring Has Sprung

[Sun Chaser]

 CoventryWeather Mixed is a lot better than the deluges of February and March!

[LetItSnow!]

Very interesting 12z from the GFS.

Different from the get go as the build of pressure actually has an imbedded trough so this would be quite cloudy and perhaps with patchy bits of rain.

Then the ridge behind the Iceland low helps to bring a northerly punch at day 10. While I do think this is probably an extreme signal, it's not entirely unfeasible. That ridge in the Atlantic will play a crucial role into whether we retrogress or whether it amplifies a UK high.

Proper northerly too with the -5 line clearing the whole country. This would bring frost even to the south which would be a bit of havoc for gardeners due to early spring growth. This would probably bring some cracking convective material too. The usual caveats of time apply...

I have a feeling that by around the 17th we'll either be heading for the beach or heading for the wardrobe to dig out our winter coats.

The set up is rather similar to April 1995 which after an exceptionally warm first-half (10.2 up til the 15th) became cold mid-month with some potent northerlies. It is a matching analogue year I've heard funnily enough.

[Mark wheeler]

Oh no

ECM

 

Gem

Edited April 6 by Mark wheeler

[Howie]

 Mark wheeler nooo

[Addicks Fan 1981]

 Mark wheeler we need to look at the smoothed version of those particular charts and I'm pleasantly surprised that it's not as bad as those charts implied and won't be as cold when it comes down to the high resolution.   The ensemble mean charts look marginally better.    

[Mark wheeler]

 Addicks Fan 1981 was hoping for a move in of high pressure from the southwest but as someone said yesterday a new trend has now revealed itself albeit transient. However as @ANYWEATHERsays below an improvement on the dross of previous weeks.

Edited April 6 by Mark wheeler

[ANYWEATHER]

Models firming up on a semi high pressure scenario,next week, firstly for southern Britain and toying with an Atlantic Ridge later ,so the rain train slowing down ,although far from countrywide settled conditions look unlikely for now ,but certainly stepping in the right direction. ...☺

[Rain All Night]

21 hours ago, Rain All Night said:

0z deterministic runs, out to Fri 12th (day 7)

The best of the more settled weather now looks like it will be at the end of next week rather than mid-week.

0z ensemble means, out to Sat 20th (day 15)

Let's hope ECM is wearing its "best model" hat today, as it's offering an appealing sequence of events to come: the Azores high extension we've already been expecting, followed by an Atlantic ridge approaching and initially sending a chilly northwesterly over us before the ridge moves directly over the UK, followed then by suggestion of further heightened activity from the Azores high. GEFS is not in concordance from the Atlantic ridge onwards (at least not on the 0z run - the 6z run is looking rather better).

Edit: Here's that better-looking GEFS 6z run.

0z deterministic runs, out to Sat 13th (day 7)

0z ensemble means, out to Sun 21st (day 15)

Gotta head out and don't have time to wait for the full ECM ensemble to load, so the first 10 days will have to do...

Edited April 6 by Rain All Night

[Summer8906]

 Mark wheeler Better than now, arguably, and certainly a lot more seasonal.

Plus one might hope that huge high in the Atlantic might move in afterwards, or at the very least lock in a dry-ish semi-anticyclonic NW-ly.

Whatever happens, it does indeed look from about Thursday onwards that spring (in its various forms) will arrive after the pseudo-autumn of the 2nd to 10th.

Edited April 6 by Summer8906

[Neil Harris]

 LetItSnow! A 1995 setup will do nicely , if it continues..

A fantastic summer

[Lee Notts]

 LetItSnow! ooh I'd take a 1995 type summer.  Probably the best summer I've known 

[damianslaw]

Longer term and outside the reliable, the models continue to pick up the trend towards mid atlantic heights and the atlantic finally quietening down, indeed far more typical synoptics for deeper spring.. knock on effect a cooling down and possibly an airflow from between west and north east, rather than the perpetual west to south east quadrant that we've been locked into for most of the last 6 months.

As said outside the reliable, but if verifies this would be a definate pattern shift, losing the omipresent azores high ridge followed by low pressure onslaught from the south west.

I think many would be happy to exchange very mild and wet/ cloudy, for dry, sunny and something average/ cooler. 

 

Lets see if the trend continues, more likely at this stage in the year to see such developments than any other stage. 

In the reliable if you like early warmth, humidity, damp or wet and windy you'll be happy with the immediate prospects, but those wanting a drying out soon will have to stay patient. 

[*Stormforce~beka*]

 Mark wheeler WIll it bring sun or snow?

[WYorksWeather]

The GFS 06z ensemble looks sort of interesting. The period around mid-month does look of interest in terms of whether we do go into a cooler spell, but equally there are still a minority of runs that send us into another insane heat spike for the time of year. Result is huge temperature variation at the 2m level between ensemble members - a range of over 20C as soon as we get to day 8-9 range.

Does look to be quite a bit of dry weather possibilities for the south - the mean keeps pressure at or above 1020mb from day 4 until the end of the run.

For more northern areas though - still a struggle to get much high pressure. The GFS OP was a very poor outlier from that perspective, but even taking the mean it doesn't look quite as convincing that high pressure will ridge far enough north to lock the whole of the UK into an extended dry period, though it should at least be drier than of late, which is a significant improvement of course still.

[Sun Chaser]

 WYorksWeather To be honest that Newcastle mean keeps pressure above 1020 from day 9 onwards as well. I think the switch we've all been so desperately waiting for may finally be arriving

[northwestsnow]

EC day 8 

 

our climate is a joke at this point.

 

[northwestsnow]

After months of rain here comes the snow ( in spring ,as i predicted months ago )..

[Cheshire Freeze]

 northwestsnow yep EC and GFS both hinting at repeated N’ly outbreaks courtesy of N Atlantic heights.

Could be some unseasonably cold nights with that set up.

Going forward it’ll be interesting to see where developing La Nina takes us. It’ll be one of two routes IMO. Heights that move E at the mid latitude (Euro heights and plumes) or heights that alternate between Greenland and Scandi, leaving the UK at the mercy of slow moving troughs (ala 2007).

What route transpires will ultimately dictate the early summer period (May-July) IMO.

Edited April 6 by Cheshire Freeze

[Azazel]

 northwestsnow its been the case for the last 3-4 springs now. Winter has moved as a season. 

[Downburst]

The long range seasonal is very odd, but does backup what crew cold predicts for summer, higher pressure further north or north east. The autumn might be nice dry and warm 

[raz.org.rain]

 Downburst weren't they saying the opposite yesterday? LRF reliability really being stretched lately.

[WYorksWeather]

 Sun Chaser I just don't fully trust it as there is a fair bit more spread further north. I'm always cautious of it downgrading to a couple of dry days for the south and that's it.

[Addicks Fan 1981]

 northwestsnow the op charts I think are not the right thing to be using now, we are better off looking at the clusters and the ensemble mean charts.   I saw the ensemble mean charts this morning and it indicated a northerly before the winds backed westerly again.   We need to be cautious on what charts we look at at this stage.

[Earthshine]

 Cheshire Freeze A 2007-style summer after these diabolical last 6 months would crush me.  Thank god I've at least got a week in Athens booked for July!

[raz.org.rain]

 Earthshine fortunately it's not particularly likely