Spring Model Discussion 21st March 2013 006z onwards...

[Methuselah]

I'd like to see Friday's incursion reach a tad further north than last Friday's, tbh, with an active frontal zone running from, say, Bristol through about 15 miles' north of Ipswich. That would do very nicely, indeed...Penzance to Calais really won't.

I see a week of N'ward/S'ward adjustments/corrections looming!

[DTHFCJ]

Well a poor run from ECM pretty hard to find any positives and remarkably the northern blocking is shown to build again in FI!!

The only positive is the cold should moderate into April slightly and given the strength of the sunshine is would feel pleasant enough out of the wind.

Still this is FI and it could be an outlier ample time for a change but the rest of March is looking cold now and the hunt for a pattern change now goes into April.

There could be a positive in that when the pattern does finally shift it will put us in good stead for summer..............

In the mean time

Northern blocking gone?

http://www.meteo.psu.edu/~fxg1/ECMWF_0z/test8.gif

or am i reading the charts totally wrong...

[Man With Beard]

Models now firming up on another snow battle this Friday but even more remarkable is the possibility of cold air winning out again and staying put for several further days. Would a time come when a cold chart would suddenly flip to warm simply due ti time of year? I'm thinking about what happens I believe in Canada - they sometimes have a one week autumn simply because the balance of hot/cold moves past an equilibrium point - likewise I'm sure that our current weather pattern (dry easterly from E Europe) could deliver 20C + by June. Would be fascinating to see seasonal changes without a pattern change. But could this happen quickly or realistically would it take a long time?

[Polar Front]

Ukraine chaos......................http://www.youtube.com/watch?v=URHLSNbG2_E

[Yarmy]

Well that was some ECM!

oh, Gavvvvvvinnnn look at this!

That chart really needs a soundtrack for Gavin and Mushy's (and Mrs Yarmy's) benefit:

[Summer Sun]

ECM short ensemble the control and Op look to be head above the zero line right at the end full ensemble will be out shortly

Full ensemble control and Op just on or just above the zero line from around half way

Edited March 24, 2013 by Gavin.

[Geordiesnow]

The good news with this afternoon runs is that the cold could very well last until the end of the month therefore the chance of one of the coldest March's remains a possibility and also the risk of widespread flooding from heavy rain, milder temps and flooding from the GFS model has reduced somewhat.

Yes eventually we want it to turn milder as we head through Spring but it has to be a slow process I feel to minimise the risk of flooding so I'm content with this afternoon runs. They also show an increasing risk of convective snow showers, especially from the UKMO run

[Backtrack]

I usually come into here hoping to see a cold run.

But Jesus, come on! I wouldn't mind thawing out sometime this century.

This weather is doing more trolling than 4chan...

[Backtrack]

Northern blocking gone?

http://www.meteo.psu...WF_0z/test8.gif

or am i reading the charts totally wrong...

Yeah... just instead we're left with masses of negative height anomalies dragging in Easterly winds from an unusually cold continent.

[snowking]

A new tool i've now got access to, at present I can only get the ensembles for Glasgow from this, but I'll see if I can get other locations added.

These from the 12z ECM ensembles, first of all, TMax and TMin:

A slight, but not particularly significant rise for the North then.

And the Tmean:

And finally (this maybe my favourite of the tools), the GFS ensemble (in green) overlaid on top of the ECMWF ensemble:

As you can see, the GFS much milder than the ECM suite this evening

SK

[bluearmy]

Naefs 12z update just as impressive week 2 as the 00z run with high anomoly re establshing to our north and staying low to our south.

[Tim Bland]

“@MattHugo81: All 51 of the EC ENS members keep the cold block in place into next weekend with an E or NE'ly. Very little precip makes it N as a resultâ€

[Hotspur62]

Well the models seem to be slowly coming round to this current spell of cold weather continuing upto this weekend.Whatever happens after next Saturday is up for debate,but remember,this time last week certain models were suggesting that by now,espicially in the South would be 10 degrees by now.That hasn't happened(the high today here was 0.6degrees!!).Just my gut feel,but i think the block in place is so strong it will need something pretty special to displace it and i think this time next week we will still be in the midst of the cold spell.This will be a March to remember like Dec2010 was

[LomondSnowstorm]

A new tool i've now got access to, at present I can only get the ensembles for Glasgow from this, but I'll see if I can get other locations added.

These from the 12z ECM ensembles, first of all, TMax and TMin:

A slight, but not particularly significant rise for the North then.

And the Tmean:

And finally (this maybe my favourite of the tools), the GFS ensemble (in green) overlaid on top of the ECMWF ensemble:

As you can see, the GFS much milder than the ECM suite this evening

SK

Cheers for those, the 'target' for Scotland is a mean for the month below 1C, which would bring this to the 2nd coldest March on record here, and the ECM certainly (given that we're sitting around 1-1.5C for the first 20 days of the month) looks likely to deliver that. The second target would be the coldest March on record here, namely March 1947, but for that we'd need a mean of around -2C for the next few days. It's unlikely but not impossible, given HP moving into the north of Scotland clearing skies here and leading to some potentially very low minima, particularly in the western Highlands and down to the unusually snowy realms of Kintyre and the Inner Hebrides. Amazing to think that Arran, an island in the Clyde where snow to low levels isn't even all that common and certainly no more so than in the central belt, has had no mains electricity for 48 hours due to blizzards which took place after the equinox.

[snowking]

ECM short ensemble the control and Op look to be head above the zero line right at the end full ensemble will be out shortly

Full ensemble control and Op just on or just above the zero line from around half way

In terms of trends though Gavin, unmistakeable that over the last 24 hours its swung cooler in the longer term

Below todays 12z EC EPS (red) vs yesterdays 12z (blue)

SK

[cyclonic happiness]

A new tool i've now got access to, at present I can only get the ensembles for Glasgow from this, but I'll see if I can get other locations added.

These from the 12z ECM ensembles, first of all, TMax and TMin:

A slight, but not particularly significant rise for the North then.

And the Tmean:

And finally (this maybe my favourite of the tools), the GFS ensemble (in green) overlaid on top of the ECMWF ensemble:

As you can see, the GFS much milder than the ECM suite this evening

SK

Look like the proton beams that the ghostbusters used? :-D

[Summer Sun]

The ECM ensemble for Birmingham shows temperature making a recovery of sorts from Easter Monday with temperatures not getting lower than 5c and not getting higher than 11c (to the 7th)

So another bitter week this week but a slightly recovery in temperatures is possible from next week with the Ens average running between 6c and 9c

Temperatures look like staying well below the seasonal average of 12c to 13c for a while yet

[Lynxus]

As you can see, the GFS much milder than the ECM suite this evening

SK

Looks good, However surely the GFS and ECM should at least START with the same values? ( Or extremely close together.. ) Seems like the GFS is just milder because it wants to be from the word go?

Or am I missings omething?

[snowking]

The ECM ensemble for Birmingham shows temperature making a recovery of sorts from Easter Monday with temperatures not getting lower than 5c and not getting higher than 11c (to the 7th)

So another bitter week this week but a slightly recovery in temperatures is possible from next week with the Ens average running between 6c and 9c

Temperatures look like staying well below the seasonal average of 12c to 13c for a while yet

Maximum values perhaps, however, if we balance that with min and average as well:

Should also perhaps add that those (along with the one you posted Gavin) are still the 0z

Last one of these I promise! GFS ensembles from the last 5 12z plots

Red is todays, Blue was yesterdays, Green Friday, Yellow Thursday, and Black Wednesday

Spot the trend...

Edited March 24, 2013 by snowking

[snowking]

Looks good, However surely the GFS and ECM should at least START with the same values? ( Or extremely close together.. ) Seems like the GFS is just milder because it wants to be from the word go?

Or am I missings omething?

I'm still getting to grips with this particular tool so i'll try and find out, but yes it is a little odd. These are the raw ensemble sets, but they match up to the corresponding data sets found elsewhere from what I can see

SK

[Panayiotis]

Its quite funny because Gavin's posts are like the ones we post when we are looking for cold.....

[Snowman.]

GFS going for the ECM solution with lower dam over the UK.

[R.P. McMurphy]

I'm still getting to grips with this particular tool so i'll try and find out, but yes it is a little odd. These are the raw ensemble sets, but they match up to the corresponding data sets found elsewhere from what I can see

SK

What's the link to this Data SK so I can view myself?

[I remember Atlantic 252]

“@MattHugo81: All 51 of the EC ENS members keep the cold block in place into next weekend with an E or NE'ly. Very little precip makes it N as a resultâ€

I think that will happen, the 12Z's got Easter weekend nailed, cold and dry for most except m4 southwards, better than GFS 00Z and 06Z though today

[Snowman.]

Very close to the ECM

Also as the dam drops showers become widespread and alot heavier.