Model Banter, Moans and Ramps Autumn/Winter 2014/15.

[I remember Atlantic 252]

This time last year, i remember models flirting with a northerly for Sat 7th Dec? cannot remember which ones but think I remember GFS was first to ditch it, showing constant Atlantic dominated charts

[Gael_Force]

This time last year, i remember models flirting with a northerly for Sat 7th Dec? cannot remember which ones but think I remember GFS was first to ditch it, showing constant Atlantic dominated charts

 

Do you not remember all the worries round potential flooding on North sea coasts? I posted the charts in MO thread last night.

 

Actual chart from 5th Dec 2013.

 

[chrisbell-nottheweatherman]

A high of 7/8C forecast here so for those in the firing line it isn't much to celebrate about. Add to that lead grey skies and drizzle then it feels just like the usual north sea cack for down here.

 

Indeed, for anyone living within 20 miles of the North Sea, a weak Easterly only results in one kind of weather.

[I remember Atlantic 252]

Do you not remember all the worries round potential flooding on North sea coasts? I posted the charts in MO thread last night.

 

Actual chart from 5th Dec 2013.

 

 

Yeah I do, was the start of the flooding throughout UK really

[Barry12]

Atlantic weather is more likely in December, so every December will be Atlantic dominated? great logic on here...

[I remember Atlantic 252]

Atlantic weather is more likely in December, so every December will be Atlantic dominated? great logic on here...

 

Saw your post in model thread matey about the GFS! think you will be around london naked

[Snowstorm1]

WINTER IS COMING - that is all.

[knocker]

ECMWF plans on increasing length of its 32-day EPS "weekly" forecasts to 45-60 days in the next year or two.

[I remember Atlantic 252]

Northerly for weekend of 13th-14th Dec being modelled a few times by GFS in deep FI, really isn't a bad run the GFS 12Z, cold shot for tues to thurs, then milder before another colder shot from the NW for Sat 6th, with a high quickly centering over us, has a potential to be very cold, especially the weekend of 6th-7th

[I remember Atlantic 252]

ECM 00Z I feel will be accurate, gone with GFS really, looks flat with westerlies from Sat 6th (inversion cold off), GFS FI looks all wrong

[knocker]

Good grief I've been threatened with the 'naughty chair'. Is it the NW equivalent of Old Sparky?

[mushymanrob]

ECM 00Z I feel will be accurate,

 

you should read what nick sussex said about the ecm, i wholeheartedly agree. (broadly good upto t144, after t144 distrust it as its prone to over amplification).

[I remember Atlantic 252]

you should read what nick sussex said about the ecm, i wholeheartedly agree. (broadly good upto t144, after t144 distrust it as its prone to over amplification).

 

I know that, I mean for weekend 6th-7th, its now showing flatter westerlies, I am the GFS believer normally, but I feel FI on 00Z will be more Atlantic dominated

[mushymanrob]

I know that, I mean for weekend 6th-7th, its now showing flatter westerlies, I am the GFS believer normally, but I feel FI on 00Z will be more Atlantic dominated

 

fair play

 

dunno... the noaa 500mb charts suggest a northwesterly upper airflow after this weeks calmer period. looking to me like switching from northerlies to westerlies either side of the front as it waves across the uk.

the coldies dont yet to have picked up very strongly on a possible pattern switch to a cold northerly IF at some point the azores high ridges northward and joins with the greenland high, thus producing a very cold spell for the uk. im watching the noaa anomaly charts for the first sign of this possinility.

on the other hand of course the azores high might just ridge in and sit by our near southwest, keeping us mild and dry... thats not currently an option, but like the cold one, might be in the future.

[I remember Atlantic 252]

fair play

 

dunno... the noaa 500mb charts suggest a northwesterly upper airflow after this weeks calmer period. looking to me like switching from northerlies to westerlies either side of the front as it waves across the uk.

the coldies dont yet to have picked up very strongly on a possible pattern switch to a cold northerly IF at some point the azores high ridges northward and joins with the greenland high, thus producing a very cold spell for the uk. im watching the noaa anomaly charts for the first sign of this possinility.

on the other hand of course the azores high might just ridge in and sit by our near southwest, keeping us mild and dry... thats not currently an option, but like the cold one, might be in the future.

 

I'll settle for the bold bit, if we cannot have inversion cold, at least have it dry and mild, rather than horrid Atlantic usual UK trash

[Hocus Pocus]

There's been some good analysis over on the MOD thread once the silly posts had been removed that is, looking mostly dry and fairly cold through the next 7-10 days thereafter all options are plausible.

[marksiwnc]

Although not quite model related and don't know If anyone has posted earlier but a post by R.J.S in the seasonal thread and is never far off the mark and seems to think that a cold month with easterly winds are expected this month. Models will need to change drastically for this to be the case but something is a foot if he thinks this. (I hope)although he does say maybe.....

Going to issue an update of previous forecast, same general theme but seeing a colder balance between mild and very cold spells.

DEC -- After a few mild days some cold anticyclonic conditions will develop, and with retrogression indicated, this may turn into an exceptionally cold mid-month period with below freezing temperatures in daytime and heavy snowfalls in eastern England and many parts of Scotland as well as exposed coasts of Northern Ireland and the Republic of Ireland. This bitter blast may be followed by slightly milder temperatures around Christmas and New Years but there is some chance of a white Christmas as recovery might be rather slight at first. Now revising December CET down to 2.0 C.

JAN -- Very stormy to start as the Atlantic tries to regain a hold against an entrenched blocking pattern over Europe. Possible severe storms around 4th to 6th at the high energy peak of full moon and northern max. These may take the form of mixed rain and snow in many areas although where winds are strongest in south, a brief thaw and heavy rainfall event associated with temps briefly near 10-12 C. Scotland may not see much of this milder air and blizzards may develop. Exceptional cold is then likely mid-month, followed by much milder weather towards the end of January. The CET may be quite low but will go with 1.7 C.

FEB -- Mild for a few days near the start of the month then blocking will return and it could produce severe cold at times. Some chance of a subzero CET month. Will say 0.1 for the verification.

MAR -- It will remain cold for most of the month then break to quite a warm end of the month but not in time to make much of a dent in a subnormal CET value around 4.5 C.

The basic difference (if any) between this and earlier forecast is that I have reduced the overall average temperatures although retaining a similar high-variability oscillation in pretty much the same time sequence. November showed only faint indications of this high-variability trend in the UK, more so in Ireland which has seen colder days recently than most of Britain, however, the hemispheric pattern is clearly winding up for a very active winter.

[knocker]

Deleted

Edited November 30, 2014 by knocker

[BlueHedgehog074]

Good grief I've been threatened with the 'naughty chair'. Is it the NW equivalent of Old Sparky?

It is indeed. But I wouldn't worry, we won't be planning to put you on it. ;P

The models, though, do seem to be showing a possible risk of a general Westerly flow taking over after the mostly settled spell this week. A chance of the ridging from the Azores High to our South-West getting knocked to our South with a flatter pattern emerging (while their is some agreement on this, especially from the GFS, it's still far enough away for some changes to occur). Though if portions of the Polar Vortex do migrate from our North-West to our East/North-East, then I suppose some pattern flattening would be expected for a time as it travels Eastwards. This could then (hopefully) allow heights to build to our West or North-West with colder air spilling down from around the North direction (similar to what some have suggested).

[sundog]

 Though if portions of the Polar Vortex do migrate from our North-West to our East/North-East, then I suppose some pattern flattening would be expected for a time as it travels Eastwards. This could then (hopefully) allow heights to build to our West or North-West with colder air spilling down from around the North direction (similar to what some have suggested).

I think that is our best chace for a proper cold spell. Until the PV moves to our east then we may aswell be pi**ing againest the wind in hoping for a proper cold spell atm.

[I remember Atlantic 252]

Models, especially ECM starting to me anyway, look like a normal December, look Atlantic dominated with wet weather to me in FI (to be expected of course)

 

Netweather forecast did warn us of a significant wind event, wonder if its showing signs in FI on the ECM

[Frosty.]

Enjoy the frosty nights this week..better than mild mush. It's only grim for those who want yet more..yawn.. unseasonable warmth. :-)

Edited November 30, 2014 by Frosty.

[Barry12]

A little surprised to see the modified 120hr fax go with their raw output but I have seen this over the last

few years, only for them to flip on the following night's 96hr chart. Barring something cropping up out of the

blue, I fear it will be quite a long waiting game for us coldies this season.

Patience grasshopper...the cold usually does come out of the blue.

[blizzard81]

Patience grasshopper...the cold usually does come out of the blue.

Heres hoping Barry.

[Barry12]

You love the Atlantic, grasshopper.