Model output discussion - 1st December onwards

[Liam J]

Just now, gottolovethisweather said:

And furthermore I think will won't largely verify as shown. 

Just posted for fun, it's looking very unsettled at times but I'm assuming something quite as bonkers as that chart won't verify! Or we'll be exhausting the storm alphabet and the poor folk already flooded will be facing even more desperate times. Just seen the Met Office warning for the weekend and they are now mentioning a risk of 150mm of rainfall!! Very worrying times. 

[nick sussex]

12 minutes ago, mulzy said:

We can say with some confidence that the broad westerly / south-westerly flow is expected to continue in the medium term - the NAEFS 16 day anomaly chart illustrates this perfectly.

 

 

Ridge over the Eastern Canada/USA, ridge over Europe, low heights over Greenland.  This pattern is not conducive for cold over the UK.  What happens after this is purely speculative.  With the warmest December on record already in the bag, I wonder what odds the bookies would give me on the warmest winter ever recorded?

 

 

 

I'd be a bit wary of looking at that day 16 anomaly given the movement of the MJO. If the MJO continues into phase 7 it could produce a positive PNA pattern and that would be ridging in the west USA with troughing towards the eastern USA. With an amplified signal that normally pulls the Azores high further west with the Euro high pushed east as the jet cuts se near the UK.

NWP is often slow to react to the MJO at far timeframes so for the timebeing its best to be cautious in terms of the pattern that far ahead.

[mulzy]

7 minutes ago, nick sussex said:

I'd be a bit wary of looking at that day 16 anomaly given the movement of the MJO. If the MJO continues into phase 7 it could produce a positive PNA pattern and that would be ridging in the west USA with troughing towards the eastern USA. With an amplified signal that normally pulls the Azores high further west with the Euro high pushed east as the jet cuts se near the UK.

NWP is often slow to react to the MJO at far timeframes so for the timebeing its best to be cautious in terms of the pattern that far ahead.

Thanks Nick viz. comments on the MJO.

Guess I'm getting a little bit ratty with some of the NWP output - even FI eye candy output has been in short supply!!

[Frosty.]

6 minutes ago, mountain shadow said:

 definitely more wintry with more Pm incursions over the next two to three weeks.

850s of -5 will be more of a visitor giving increased snow chances over high ground in the North.

I must have read a different MO outlook to you then! I could swear there was nothing remotely wintry about it aside from a few isolated slight ground/air frosts during quieter interludes in the south.

[nick sussex]

20 minutes ago, mulzy said:

Thanks Nick viz. comments on the MJO.

Guess I'm getting a little bit ratty with some of the NWP output - even FI eye candy output has been in short supply!!

You're not the only one! lol

If you take December so far its been like a stuck record in terms of the NH pattern. At the moment we have a variable that being the MJO which is now moving so this is the first time we've seen something that could shuffle things up. Of course there are no guarantees so I don't want to put high expectations on this. I'm keeping an open mind and will just see how things play out. Having said this one of the leading MJO experts over at NCEP has suggested that the MJO movement could change the pattern in the USA. At this point If I had to make a call I think the pattern is likely to be edged eastwards with the jet angling in more towards the UK.

Preferably we'd like to see high pressure to the ne and not a Scandi high which is too far east to do any good slowly sinking, the former would put more forcing on low pressure near the UK and help pull the jet se.

We'll see over the next week whether the models respond kindly to the MJO.

Talking of the MJO, the GEFS and GEFS BC have both updated, both continue to increase the strength of the MJO, the former into phase 7, the latter high amplitude 6, the GEFS BC has been least bullish about phase 7 but if we had believed its forecast of last week it would still be marooned in a low amplitude phase 4! Still waiting for the Euros to update.

Edited December 23, 2015 by nick sussex

[Interitus]

21 minutes ago, *Sub*Zero* said:

Just posted for fun, it's looking very unsettled at times but I'm assuming something quite as bonkers as that chart won't verify! Or we'll be exhausting the storm alphabet and the poor folk already flooded will be facing even more desperate times. Just seen the Met Office warning for the weekend and they are now mentioning a risk of 150mm of rainfall!! Very worrying times. 

Why won't it verify?

Don't fall for the old 'too-many-isobars-because-they're-at-1mb-intervals' trick!

[Eskimo]

The minor differences between the 06z and the 12z at just 120h out. Not that it would make much difference but the main lobe of low pressure looks more negatively tilted. 

06z 

12z

[booferking]

Yep that is completely of the scale if that hits Ireland will end up in the arctic then we will definitely see some snow.

And if the first storm don,t the second will make sure of it haha crazy.

Edited December 23, 2015 by booferking

[Ravelin]

8 minutes ago, booferking said:

Yep that is completely of the scale if that hits Ireland will end up in the arctic then we will definitely see some snow.

And if that one doesn't do the job the next one will...

[Red Raven]

Its not looking good for us up here in Cumbria this weekend. That rainfall keeps on showing and seems to be gaining in intensity. If the 12z are correct the recent floods of 5th and those of 2009 will be minor shows in comparison.

[booferking]

7 minutes ago, Ravelin said:

And if that one doesn't do the job the next one will...

Seen that scary times ahead if that verifies, last time i seen a storm like that was boxing day storm 1998 and we hit gust of 100mph was fixing powerlines for 3 weeks after that one good job i have changed jobs since then haha.

Edited December 23, 2015 by booferking

[Swave Snow]

6 minutes ago, booferking said:

Seen that scary times ahead if that verifies, last time i seen a storm like that was boxing day storm 1998 and we hit gust of 100mph was fixing powerlines for 3 weeks after that one good job i have changed jobs since then haha.

Would it be blizzards as well

[chrisbell-nottheweatherman]

1 hour ago, hooch5 said:

 

 

Back OT, I'm very concerned about both the stalling front on Christmas Day for the north-west and that monstrous Atlantic LP for all of us at the New Year.

Edited December 23, 2015 by ajpoolshark

[bluearmy]

12 minutes ago, Greenland1080 said:

Think they need to pull the GEM upgrade off the shelf!

at least its consistently wrong !

[booferking]

25 minutes ago, Swave Snow said:

Would it be blizzards as well

Yea that looks possible as well..

[Captain Shortwave]

4 minutes ago, booferking said:

Yea that looks possible as well..

Unfortunately no snow

The 850s are far too high, there maybe wintriness over the mountains from any showers that form between the two storms, otherwise heavy rain albeit the rain passes through quickly.

At this point a lot can change, but to be honest I would rather not see a pattern change from our current set up to a 2013/14 re-run.

[The PIT]

1 minute ago, Captain Shortwave said:

Unfortunately no snow

The 850s are far too high, there maybe wintriness over the mountains from any showers that form between the two storms, otherwise heavy rain albeit the rain passes through quickly.

At this point a lot can change, but to be honest I would rather not see a pattern change from our current set up to a 2013/14 re-run.

Exactly and a deep FI chart so it would be extremely unlikely verify as it is.

[bobbydog]

wow......

 

happy new year.....

Edited December 23, 2015 by bobbydog

[Cloud 10]

35 minutes ago, Greenland1080 said:

Think they need to pull the GEM upgrade off the shelf!

 

 

Its a shame they couldn't "upgrade" the other models in a similar fashion.

 

The GFS new year output is already making me feel rather uneasy.

[Polar Maritime]

Certainly a chance of snow within the systems as it pulls cooler air in at times from the N/W especially with elevation. Some proper Winter storms on the way if the GFS materialises. Quite an eye opener, And not good news for the already flooded areas with yet more heavy rain associated within these deep systems. 

 

Edited December 23, 2015 by Polar Maritime

[nick sussex]

Quite a few GEFS at day ten show a positive PNA developing.  By day 11 this is even more pronounced with the Azores high displacement. Are we seeing the first signs of a MJO induced change?

For newer members the PNA stands for Pacific North American pattern, in the charts below the one on the left show areas of higher pressure, orange/red and lower dark blues/purples. Normally with an eastern USA trough if you have enough amplification the Azores high displaces further west and low pressure sets up more to the east of the UK. This would be a marked change in pattern and would remove the Euro high from the south which has set up for the last month with the jet angled more se.

If you get enough upstream amplification you can get a northerly toppler scenario or at least some decent PM shots. Much depends on the response to the MJO signal.

Lets hope the ECM follows this trend and its still early days so we'll just have to hope that we can get some change to the relentless mild conditions.

 

Edited December 23, 2015 by nick sussex

[mountain shadow]

22 hours ago, chrisbell-nottheweatherman said:

 

Horrendous run for Cumbria and the North West. Heavy rain throughout and if the extreme storms coincide with high tides there will be coastal flooding too.

 

[Bullseye]

Light at end of the tunnel? Although seems to be hints of pattern change lately problems where would be 360hr out and no support! I don't think this tweet really shows classic -NAO although I may be wrong.

[Cloud 10]

ECM 12z at day 5 looks to be lining up a storm.

 

 

Thar she blows at day 6.

 

 

Next one should track further south.

Edited December 23, 2015 by Cloud 10

[mud_error]

evening 

just checked the latest and seen the output for here on Boxing day. Can't quite believe it. What's causing the front to stall? or is it another one of those   horrible lined up with the isobars long fetch rain forever systems from hell again?

Would really like to get a feel for the reliability of this, given the significant change from the prior run as I might be building heavy walls tommorow as a result!