Model Output Discussion - What does April have in store?

[Frosty.]

That becomes a really good Ecm run for warmth and fine weather..better than the 00z and that was pretty good!

Edited April 13, 2019 by Frosty.

[Frosty.]

With Easter on the horizon, tonight's Ecm 12z ensemble mean really compliments the eggsellent operational, quite a warm up is expected with increasing amounts of sunshine later next week which includes the long easter weekend. It looks largely settled with high pressure / strong ridging generally controlling our weather apart from a little rain in parts of the west early next week and temperatures could be close to the low 20's celsius next weekend, at least across southern uk.

Edited April 13, 2019 by Frosty.

[Singularity]

Looks like as the final warming-aided HLB spell finally subsides we see a ‘Nino switch’ flipped with a typical struggling Atlantic trough and Scandinavian high combination.

Thats the usual predominant pattern with a weak Nino and low solar activity in Apr-July. Settled increasingly warm/hot spells punctuated by destabilisations by shallow troughs which tend to provide some thundery entertainment.

Remains to be seen what complications we see from, for example, the cold anomalies in the SSTs just S of Greenland (may keep the jet stronger  and HP further S) and the low Arctic sea ice (may enable stronger Scandinavian highs than usual even for the Nino base state, along with more Azores High interplay - if the next few months turn out unusually dry it’ll most likely be the the low Arctic sea ice responsible).

[Methuselah]

Not a bad end to the GFS op, this morning; even some nice T850s, by the Arctic Circle:

 

 

And the FV3 is nae bad either: 

 

Lastly, the ensemble:  

[Summer Sun]

The advantages of a late Easter are we've a greater chance of warmer temps and this year is no eggception

Cracking stuff

[summer blizzard]

I cannot post the chart on my phone however the pressure build we have seen and will see is reasonably well supported for another week or so as a result of a Nino standing wave which setup near the dateline until recently. 

 

It did give way which allowing for a lag should allow the westerlies to return late in the month and through early May but it has been a repeating pattern and so i would expect another wave to set up which allowing for lag is probably going to produce a pretty settled (so likely warm) mid to late May period.

[Methuselah]

Things still look set for a stonking bank holiday:

  

[MATTWOLVES 3]

Bank Holiday stunner alert coming up folks..... Make sure your sun smart!

[Methuselah]

And we should be still basking on Tuesday:

 

But, as a caveat, who recalls May 1980 -- when things didn't evolve into the marvellous summer so many were predicting?

 

Edited April 14, 2019 by Ed Stone

[Frosty.]

Just had a peek at the GEFS / ECM mean and it's clear there is some fantastic weather on the way, especially by the time Easter arrives, warm with plenty of sunshine.

[Methuselah]

Good to see that there's still little sign of any Arctic rubbish:

 

[Derecho]

Looks like we have some fine Easter weather on the way with some warm SE winds . According to the 6z I'd go for the following

Friday - Maximums of 14C-19C, high cloud in the west with the chance of an odd shower on higher ground. Warmest in the South, West and Scottish highlands

Saturday -  Maximums of 15C-22C, warmest in the aforementioned areas, coolest in the east. Cloud cover minimal away from the Scottish border. Chance of a sharp shower over the far SW

Sunday - Maximums 16-22C, warmest in the south and scottish highlands. Little cloud although a chance of light showers over Welsh hills

Monday - Maximums 17-22C, probably warmest around Cambridge or the Wash. The odd shower may pop up over parts of Central England

So a fantastic Easter could be in store and pretty warm too! Though the east may be a bit cooler...

So much for the coldest April on record!! 

[Methuselah]

Could we be on the cusp of something special -- again?

  

[BlueHedgehog074]

According to some of those charts, the next few weeks could feel more like Bake-pril! (sorry I couldn’t resist lol)

Edited April 14, 2019 by DiagonalRedLine

[Methuselah]

The GEFS mean looks mean!  

[Frosty.]

According to the GEFS 6z mean it's going to be a Good Friday..Saturday..Sunday..Monday

 

 

[Frosty.]

Longer term here's a few more summery charts in late April!!

Edited April 14, 2019 by Frosty.

[MATTWOLVES 3]

Even the CFS wants to get in on the action, a definite warming trend, could we be looking at the 2nd fine warm Bank Holiday April on the bounce..... 

[Earthshine]

Is my 10.5C (I think) prediction for the April CET not out of the question then?    I can dream!  In the meantime just look at how we will see warm air being pumped into the Arctic.  ecm500 (1).webp

[Mike Poole]

17 hours ago, Singularity said:

Looks like as the final warming-aided HLB spell finally subsides we see a ‘Nino switch’ flipped with a typical struggling Atlantic trough and Scandinavian high combination.

Thats the usual predominant pattern with a weak Nino and low solar activity in Apr-July. Settled increasingly warm/hot spells punctuated by destabilisations by shallow troughs which tend to provide some thundery entertainment.

Remains to be seen what complications we see from, for example, the cold anomalies in the SSTs just S of Greenland (may keep the jet stronger  and HP further S) and the low Arctic sea ice (may enable stronger Scandinavian highs than usual even for the Nino base state, along with more Azores High interplay - if the next few months turn out unusually dry it’ll most likely be the the low Arctic sea ice responsible).

Very interesting, I always enjoy reading your posts, and I agree with almost all of this.

It is the first sentence highlighted in bold that I would like some clarification on, because as far as I an see, the final warming hasn't happened yet!  Zonal winds chart shows we're still with winds strong beyond 1 standard deviation in the stratosphere, although with a strong GFS forecast for them to tank through zero in the next few days.

So it isn't clear to me how this aids the HLB we've seen the last two weeks or so.  Are they both a result of a third process?  Personally, I have no explanation for why the HLB has materialised now, to be honest.  Other than that it often does at this time of year, which is rather unsatisfactory.

Edited April 14, 2019 by Mike Poole

[chrisbell-nottheweatherman]

6 hours ago, summer blizzard said:

I cannot post the chart on my phone however the pressure build we have seen and will see is reasonably well supported for another week or so as a result of a Nino standing wave which setup near the dateline until recently. 

 

It did give way which allowing for a lag should allow the westerlies to return late in the month and through early May but it has been a repeating pattern and so i would expect another wave to set up which allowing for lag is probably going to produce a pretty settled (so likely warm) mid to late May period.

Although it might not be popular for many here, those of us in the east could do with a wet week or so around the end of the month in order to encourage crop/pasture growth and improve river levels.  I for one would be grateful if you could continue to inform us as to whether the expected loss of amplitude of the standing wave remains in the outputs over the next week or so, please.

[Singularity]

21 minutes ago, Mike Poole said:

Very interesting, I always enjoy reading your posts, and I agree with almost all of this.

It is the first sentence highlighted in bold that I would like some clarification on, because as far as I an see, the final warming hasn't happened yet!  Zonal winds chart shows we're still with winds strong beyond 1 standard deviation in the stratosphere, although with a strong GFS forecast for them to tank through zero in the next few days.

So it isn't clear to me how this aids the HLB we've seen the last two weeks or so.  Are they both a result of a third process?  Personally, I have no explanation for why the HLB has materialised now, to be honest.  Other than that it often does at this time of year, which is rather unsatisfactory.

Hi Mike,

Good question there. I see the cause for confusion here; what I called the final warming is actually more of a tropospheric-driven lower-mid-stratospheric warming that looks to either set in motion or coincide with the beginning of the final warming in the coming week.

A decent dual-anticyclone pattern (wave-2) here - this being what we didn't have enough off back in late Dec and early Jan to produce a pure split-vortex type SSW rather than the messy hybrid that didn't work out well for E&W cold and snow enthusiasts (Scotland's seemed pretty snowy, though perhaps not by their own standards?).

 

Goodbye and good riddance, Mr. Vortex!

[Methuselah]

Friday still looking good: 

[MATTWOLVES 3]

A very interesting article from judah Cohen regarding the current situation at..Arctic oscillation https://www.aer.com.

[I remember Atlantic 252]

4 minutes ago, Ed Stone said:

Friday still looking good: 

good if you like sea fret, looks a classic setup where mist lasts post 2pm

but sunny from start to finish for most areas