GFS FI not so clean cut tonight.

Of course here in Cumbria a South Easterly is great in Spring but the charts not so good tonight.

MetO MRF is very settled so be honest April is anyones guess.

Andy

So... despite most of the LRF models having been keen on a regime of high latitude blocking and troughs tracking well south in the Atlantic, we're now seeing a signal from some of the shorter range models for lower pressure to the NW with higher pressure to the E and SE.

I must say, I'm not convinced - I reckon we may see the Atlantic troughs tracking further south but also making less progress eastward. In other words, a continuation of this week's theme, with conditions likely alternating between warm, largely settled days and nearer average, more unsettled days - a healthy mix, you might say 

If it's anything like the CFS winter forecasts from last Autumn that signals a very different July from last year - cool and wet! Anything the CFS shows take the opposite and you're often not far wrong...

The warm theme continues this morning on the model output, some rain about this week though.

Just bear it in mind - lets not get too carried away.

First Spanish plume of the season - already?

Just a note - the air quality across parts of the UK is poor at the moment and it will get worse before it gets better. Some of you may have noticed it has been very hazy today. The E-SE winds seem to be dragging pollutants off the continent. Worst days at present look to be Mon-Wed especially across central and southern parts of the UK, so if you have any cronic health problems to do with breathing might be best stay indoors or restrict time outside.

Just to add to the pollution issues we are having >>> http://uk-air.defra.gov.uk/forecasting/

ECM again going for a drier theme with potential "mini" heatwave by the end

Other models seem more unsettled with potential for some big showers and storms pushing up from Iberia

And probably/hopefully  some warm stuff as well.

Get rid of this SE polluted air would be a start!

Bands of showery rain pushing north at times thoughout the week with the risk of thunder but remains very mild.

http://cdn.nwstatic.co.uk/ecmimages/20140330/00/ecmt850.240.png

Fair to say that would be exceptionally warm where the sun shines, I daresay mid-20's would not be out of the question if the skies were clear enough.

With GFS also trending towards this based on the 06z op compared with the 00z op, there is scope for something 'special' to evolve.

The phrase 'what goes up must come down' does come to mind, though - the northerlies in GFS FI from both the 00z and 06z are a reflection of this potential.

In the nearer timeframe, ECM shows how we could avoid the cooler westerlies almost entirely, should LP track to our south with the HP to the NE more resilliant than previously modelled.

There's no other model support for that yet though - even UKMO continues to show a weak LP tracking north across the UK rather than staying to our south. So that remains the favoured option in terms of the model output.

Which means.........

What is the future for this warm spell.

GFS now looking the most settled and potentially hot in the south.

UKMO and ECM very unsettled.

In other words, its all up for grabs.

In the meantime, some big showers possible this week

ECM is not what I'd call very unsettled, it brings one storm system through from the west in 8 days time, clearing it to Scandinavia by day 10 with a ridge incoming from the SW.

Meanwhile, UKMO is rather unsettled, I agree. It hasn't given up on the idea of a trough wedging itself close to the UK from around Friday, whereas the other models now keep most of the energy further out to our west.

GFS is far closer to ECM than UKMO, but with the Atlantic not as vigorous as the former. The theme of mid-latitude blocks favouring a location close to our NE makes itself known again in FI on the 00z op run.

A ridge from the south with very warm conditions is now shown by the GEM run, and once again it's an isolated evolution, with a more changeable or unsettled and cooler spell - lasting a few days or a few weeks, we can't really tell - still the favoured option, this most likely starting from either Saturday or Sunday unless we see further delays in the trough progression.

South and East gets the best of the weather...

Erm. The GFS 12z op run is... staggering.

http://cdn.nwstatic.co.uk/gfsimages/gfs.20140331/12/171/h850t850eu.png

Following the much warmer than average conditions for many of us out to Saturday, a brief cooler interlude across the weekend is followed by the Atlantic digging south out to our west and providing upstream support for a vast ridge across Europe. This idea was shown by ECM on yesterdays 00z op run but was then dropped and remained very much absent on todays 00z op run.

At this stage, the GFS op run shows very mild nights across England - at 9 to 11*C minimum - being the source of high CET returns, with the daytime maxima supressed by a trapped frontal system - though still reaching the mid-teens widely.

http://cdn.nwstatic.co.uk/gfsimages/gfs.20140331/12/192/h850t850eu.png

By Tuesday, skies are clearing more, and temperatures climb above 20*C widely across the SE.

http://cdn.nwstatic.co.uk/gfsimages/gfs.20140331/12/240/h850t850eu.png

We then see the next in a long series of blocks to the NE keeping us in the warm airmass, and as we lie in the col between the Atlantic and block, light winds give pleasant days with temperatures above 20*C somewhere in England on each day.

http://cdn.nwstatic.co.uk/gfsimages/gfs.20140331/12/300/h850t850eu.png

The Atlantic then undercuts and drops quickly to the Med. which serves to keep us in the warm air, 20*C continuing to be hit somewhere in the UK every single day, which continues to a peak on Tuesday 15th when 22*C is shown for the SE (which we know would likely lead to 24*C or so in favoured spots).

Even from there, it only cools down due to an incursion of cooler air around a new ridge building strongly across from the Azores, with warmer air likely to return before too long.

Put simply, April 2014 would start to eat April 2011 for breakfast if this GFS op run verified.

That's a big IF though, and we really need to see what ECM comes up with this evening before considering the possibility much.

UKMO is out, but it's not all that clear from its 144 hour chart where it would go; the trough across the Azores isn't pointing south as much as GFS has it, indicating a less sharp jet buckle, but on the other hand, the trough is further west than GFS has it...
The decider is that shortwave pulling away from the Azores trough, which would at least delay the ridge. The model has trended to a stronger Euro ridge, though - so it does seem to be something to keep a close eye on.

Comparing the 12z GFS op run in FI with April 2011 out of interest, I can see than in 2011, there was a lot less PV energy across Siberia, and the U.S. saw less in the way of trough activity as the PV core was centered right over Greenland rather than more across Canada.

Warm and dry Aprils in the UK can arise from a variety of N. Hemisphere setups... I'm trying to recall whether they actually had much correlation with cool and wet summers or not...?

http://cdn.nwstatic.co.uk/ecmimages/20140331/12/ecmt850.192.png

This is ridiculous - the distance between GFS and ECM is beyond belief!

A CET prediction nightmare!        

http://modeles.meteociel.fr/modeles/gem/runs/2014033112/gem-0-168.png?12

GEM seems to be more like GFS, in fact it gives the ridge more influence from day 7.

http://www.meteociel.fr/modeles/jma/archives/2014033112/J192-21.GIF

Perhaps this is a reasonable halfway house from JMA..?

ECM sure is out on a limb, modelling a notably stronger westerly flow, one that drives energy NE from the Azores right through the UK rather than being steered north of the UK by the ridge across Europe. It makes the difference between mild southwesterlies or southerlies and a chilly NW'rly or northerly.

Fact is, though, that GFS is out on another limb - the two models represent the far extremes of the output this evening.

To gamble on an extreme, or stick with a halfway house? 

Yes very interesting run from ECM - is it a one off or a trend?  This would be in-line with what a lot of long range models are predicting for April as in Gavin's recent video - however early days yet and ECM may swing back in the morning so one to watch. ECM apart from a slight nod from JMA is as you say is out on a limb - a big change from the earlier run, GEM is siding more with GFS as mentioned. All eyes on tomorrow's ECM I think and the overnight GFS  / GEM to see any signs of a change from today's runs.

Bearing in mind what happened in 2007 and 2011 - I find the prospect of a warm April quite frightening.

We've been here before and the summers following were very poor or disastrous.

I don't really like to do comparisions but the middle of April 2003 was very warm indeed (25C in some parts of the country) and look how hot the following Summer was.

April 2003 was warm in a different format - I knew someone would mention that one - and that April was a big saving grace to the concept of warm Aprils = bad summers.

March 2003 was very good - a bit like this one - so perhaps hmmmm - things maybe different this year. I would like to think so.