Model output discussion 10/02/21

[Northernlights]

17 minutes ago, General Cluster said:

If I remember rightly, early April 1968 saw something just like that? Again, so long as memory serves, it was 21C on the Monday, and snowing on the Wednesday morning. In Milton Keynes!

PS: Also had 15cm of snow late on April 11 1978!

Your memory is correct although mine was slightly out in the White Easters thread as it was the first week of April with some snow lying till Easter on the 14th April.It snowed most nights through that first week and topped up  any areas that melted a bit during the day with icicles forming in the late afternoon from the roofs.

[Scorcher]

40 minutes ago, Empire Of Snow said:

Maybe because it's just a 30h warm spell? Blink and you'll miss it. In addition, children have Easter holidays, everything is still closed and on Tuesday the parks will be packed. Good luck with that. 

The cold spell it's not well in FI, it's consistently in every single run since 3 days ago with some variations. 

 

You can't just brush this off- short or not, Tuesday is looking like being an exceptionally warm day.

It's also longer than 30 hours. Monday to Wednesday for much of England. 

And the true cold IS still in FI- FI is after 144hrs...

[The Northern Ramper]

21 hours ago, Ramp said:

In normal circumstances you would dismiss the Gfs vs the Ecm but not with pressure around Greenland. This is a strong area for the GFS in a period of the year more conducive for high level blocking.

24 hours down the line and everything is moving towards the gfs.

[Empire Of Snow]

21 minutes ago, Scorcher said:

You can't just brush this off- short or not, Tuesday is looking like being an exceptionally warm day.

It's also longer than 30 hours. Monday to Wednesday for much of England. 

And the true cold IS still in FI- FI is after 144hrs...

I think you're missing the point of my post. Even if it's a 48h warm snap there is cross agreement in models right now for a quite prolonged cold spell after this. These models have high verification stats even at 192h when forecasting blocking patterns in Spring. The first Easterly might not bring uppers of - 8 but an inevitable Arctic blast after this can easily bring uppers of - 9 or - 10 even - 12 in parts of Scotland. 

[Scorcher]

7 minutes ago, Empire Of Snow said:

I think you're missing the point of my post. Even if it's a 48h warm snap there is cross agreement in models right now for a quite prolonged cold spell after this. These models have high verification stats even at 192h when forecasting blocking patterns in Spring. The first Easterly might not bring uppers of - 8 but an inevitable Arctic blast after this can easily bring uppers of - 9 or - 10 even - 12 in parts of Scotland. 

No I think you missed the point of my original post that you quoted.

You can't deny that there could be some significantly warm temperatures on Tuesday which is nailed on now.

No matter what the verification stats say, there is always a degree of uncertainty more than 5 days out.

You'd think the warm spell wasn't happening if you were stumbled across this forum with no knowledge of the models.

20C+ in March outside the SE is more unusual than a max temp in the mid to high single figures in early April which is what will probably happen.

[Methuselah]

Anywho, it's good to see those >20Cuppers building nicely!   

[feb1991blizzard]

GFS 6z is a stonker.

And by the way @Scorcher the -10c uppers slamming across the whole country with heavy snow showers and significant accumulations in the North in April is quite rare.

Edited March 27, 2021 by feb1991blizzard

[Methuselah]

4 minutes ago, feb1991blizzard said:

GFS 6z is a stonker.

And by the way @Scorcher the -10c uppers slamming across the whole country with heavy snow showers and significant accumulations in the North in April is quite rare.

If only there were a 'Oh, no!' response.

[feb1991blizzard]

Just now, General Cluster said:

If only there were a 'Oh, no!' response.

If only it would get to T0 and there was an oh yes response and the country blanketed in heavy snow.

[MATTWOLVES 3]

1 hour ago, Scorcher said:

You can't just brush this off- short or not, Tuesday is looking like being an exceptionally warm day.

It's also longer than 30 hours. Monday to Wednesday for much of England. 

And the true cold IS still in FI- FI is after 144hrs...

We can't brush off that day or 2 of warmth your correct..but likewise we can't brush off a screaming Ntly with possible -10c uppers a few days later! I hope you have your factor 10 ready for that warm and sunny day,but then your factor 20 ready for the freeze up withthe sun reflecting off the snow a few days later!! Bit like a skiing Holiday this

Amazing sypnotics guys just like the good old days.

[minus10]

Yes, the synoptics currently being shown on the models and in particular the latest ECM are , even for spring , pretty amazing in my opinion. Although i dont have the historical knowledge of others in relation to these things, the ecm goes from almost having plus 10 850s on 30th March over the south east to minus 10 850s over almost the whole country by Monday 5th April: a change of 20 degrees. 

In addition this is some long fetch northerly being lined up..

Tracing the isobars it goes from the the other side of the artic almost down to the south of spain...

Whether you like it hot or cold these synoptics are pretty interesting to say the least...

[The Northern Ramper]

1 hour ago, Scorcher said:

No I think you missed the point of my original post that you quoted.

You can't deny that there could be some significantly warm temperatures on Tuesday which is nailed on now.

No matter what the verification stats say, there is always a degree of uncertainty more than 5 days out.

You'd think the warm spell wasn't happening if you were stumbled across this forum with no knowledge of the models.

20C+ in March outside the SE is more unusual than a max temp in the mid to high single figures in early April which is what will probably happen.

It’s akin to a 48 hour toppler in winter when a Bartlett has cross model agreement at day 7.

[I remember Atlantic 252]

lockdown/quarantine end now in sight, think we all know it will be unsettled from April 12th, but don't expect this

[Northernlights]

11 minutes ago, MATTWOLVES said:

We can't brush off that day or 2 of warmth your correct..but likewise we can't brush off a screaming Ntly with possible -10c uppers a few days later! I hope you have your factor 10 ready for that warm and sunny day,but then your factor 20 ready for the freeze up withthe sun reflecting off the snow a few days later!! Bit like a skiing Holiday this

Amazing sypnotics guys just like the good old days.

Yes just like the good old days.Always plan to have enough feed to keep cattle in till middle of May but recent years seem to make that unnecessary.Old traditional farm tenacies always started and finished on 31st May with the sowing of crops continuing into May. Also most of Scotland is closer to the Arctic circle than Moscow so spring snow fall was very common. A very traditional spring coming up.Warmth probably around the 20th of April when the swallows arrive and the geese depart

My own opinion is that we have returned to slightly more traditional seasons  in the last 12 months with the lack of air and ground based pollution. The brown  ring  of pollution observed at the edge of earths atmosphere has probably gone (just like in the few days after 9/11 )  to be replaced with a white ring.

Based on the above my hope for the summer is one of three fine days and thunderstorm so something for everyone

[feb1991blizzard]

-6c mean engulfing the UK with -8c the North, the tide beginning to turn back in our favour again at long last, more runs between -10c and -15c than at any point during winter ironically. The 'only in winter' brigade would be salivating at the mouths if this was in early January.

 

A god few go between -15c and -17c in Northern Scotland.

Edited March 27, 2021 by feb1991blizzard

[Daniel*]

GFS 06z was the coldest/wintriest run I’ve ever seen for this late it is one for archives. Doubtful it will happen but models are playing with unusually potent -NAO regimes even for spring. First week of April is looking to start seriously below average. 

[ribster]

1 hour ago, Scorcher said:

No I think you missed the point of my original post that you quoted.

You can't deny that there could be some significantly warm temperatures on Tuesday which is nailed on now.

No matter what the verification stats say, there is always a degree of uncertainty more than 5 days out.

You'd think the warm spell wasn't happening if you were stumbled across this forum with no knowledge of the models.

20C+ in March outside the SE is more unusual than a max temp in the mid to high single figures in early April which is what will probably happen.

Indeed, it will make it feel all the more cold later in the week, thanks to the brief warm up, proper shock to the system! Mind you, cold enough out today on the bike, that wind has some bite!

[kold weather]

Regardless of whether the models are overdoing the cold (thT cold is a 1 in 25 year jobbie) there is a very strong signal for a strong cold shot with probably plenty of snow showers digging in. This time of year convection likely to develop inland to some extent which makes snow showers more likely inland even in a less optimal flow due to stronger precip.

Tuesday in particular does look very warm and has been upgrading as we move closer in. Could well see us edging towards 23-24c in local spots.

Beyond that I think there is strong evidence of a snapback to a sustained cold period, and given a much weaker Atlantic, I suspect it holds for a 10-15 day period before imo another snapback to warm, maybe very warm towards end of month 

[ICE COLD]

Everyone has covered most of the output this morning . Some of the cold being predicted is mental . Look at this from the Gem -15s into Scotland

[feb1991blizzard]

Certainly doesn't represent a usual April snow row / uppers graph, blimey with the exception of 18 and this winter just gone, we would have taken this in any winter since 13!

[BlackburnChris]

42 minutes ago, ICE COLD said:

Everyone has covered most of the output this morning . Some of the cold being predicted is mental . Look at this from the Gem -15s into Scotland

Quite something , I am very surprised the forum is so quiet .. I Suspect some of the usual Winter members have no Idea about this upcoming Cold spell as they haven't bothered looking at the charts after this long boring spell .. I think there is still some debate on weather we will get an Easterly before the Northerly , but if we do convection will be so much better than last time , and for higher areas , that could bring some very heavy Snow showers  (big flakes) . On to the 12z's 

 

On a Side note , it is good the timing of the Cold spell is now , as it would ruin the hospitality industries chance of making a profit , when they open outdoors only on 12th April , hopefully we will be warming up by then ..

Edited March 27, 2021 by BlackburnChris

[damianslaw]

So where are we today? Immediate prospects a change to very mild, locally warm conditions through early part of the new week, thanks to a pulse of warm uppers from the SW in association with a strong ridge of heights out of Iberia. However, changes are taking place upstream, and we have significant amplified flow developing off the eastern seaboard. End result warm air advection through west Atlantic enabling a strong ridge to develop over mid Atlantic.

The Iberain ridge is quickly kicked to touch by these greater forces, and we end up quickly on the colder side of the polar front jet, with mid Atlantic heights and cold air advection out of the arctic on their eastern flank.

A big switcharound forecast mid week, the models thereafter showing a cold Easter period throughout, possibly very cold. I'm alarmed by the depth of cold being shown on some if the models, sub -15 uppers into far north, GFS 6z showing sub 510 dam air 6 April, quite exceptional stuff!

All conjecture at this timeframe, attention is turned to how warm it becomes Tuesday first..

After weeks of very quiet uninteresting weather, we have a very interesting period ahead.

[Frosty.]

For sure there’s a very strong unseasonably wintry signal for early April according to the GEFS 6z mean / perturbations ️ ...small sample here, there were so many I couldn’t post them all....having followed this trend for some time I’m actually quite excited by the potential for a potent wintry blast early next month..if it downgrades, so be it (I’m used to downgrades)..but to me it’s a win win situation at this time of year with the clocks about to go forward in the early hours! ? anyway....I’m going to enjoy the enhanced spring / almost summer like warmth and unbroken sunshine early next week and then let the chips fall where they may..!!  

 

 

Edited March 27, 2021 by Jon Snow

[Djdazzle]

32 minutes ago, Jon Snow said:

For sure there’s a very strong unseasonably wintry signal for early April according to the GEFS 6z mean / perturbations ️ ...small sample here, there were so many I couldn’t post them all....having followed this trend for some time I’m actually quite excited by the potential for a potent wintry blast early next month..if it downgrades, so be it (I’m used to downgrades)..but to me it’s a win win situation at this time of year with the clocks about to go forward in the early hours! ? anyway....I’m going to enjoy the enhanced spring / almost summer like warmth and unbroken sunshine early next week and then let the chips fall where they may..!!  

 

 

If this was winter, we’d be praying those cold charts came off. They have no place in April though - yuk.

[feb1991blizzard]

Here she comes again - carbon copy of last few x output runs!