Model Discussion - 10th March Onwards

[Weather Wizard]

We are certainly in an unsettled pattern now and just in time for those in the south who are just hours away from Hose pipe bans, the 10 Pecipitation outlook shows that there will be rain around for those in need of it

All the models this morning point to only one thing and that is unsettled weather during the first half at least of the month giving ample Opportunities for rainfall

If you look at the anomaly chart much of the UK is actually only getting normal (100%) rainful we need more than this to overcome the drought. However it is a start

[shedhead]

If you look at the anomaly chart much of the UK is actually only getting normal (100%) rainful we need more than this to overcome the drought. However it is a start

Those anomoly charts are OK as a guide, but that's as far as it goes. From the info below you can see that some of the hitherto driest areas have already seen significant 24hr rain totals (if you have access to the NW radar take a look at the 24hr accumulations for a far better representation) and the latest runs suggest there's plenty more where that came from.

Courtosy of weatheronline...

Stations: Precipitation Bridlington (19 m) 38.0 mm Holbeach (2 m) 26.0 mm Cranwell (62 m) 26.0 mm Leconfield (7 m) 23.0 mm Fylingdales (262 m) 22.0 mm Loftus Samos (159 m) 22.0 mm Waddington (68 m) 21.0 mm

Edited April 4, 2012 by shedhead

[Summer Sun]

If you look at the anomaly chart much of the UK is actually only getting normal (100%) rainful we need more than this to overcome the drought. However it is a start

That's the thing at the moment any thing is better than nothing, although not massive amounts it will help in the short term

[mezzacyclone]

An Easterly is showing on the GFS albeit later in the run.

And the same with ECM

Viable to keep an eye on then PM, but I`m sure I`m not alone in favoring some form of a elongated NE to SW euro-high type setup to possibly allow a Biscay disturbance? A highlight for the storm-watchers amongst us this time of year, although not on offer, as too often the case?

[Polar Maritime]

Some very cold air aloft over the next 24hrs pushing into the central belt.

[Thundery wintry showers]

All models are agreed on a transition towards a more unsettled outlook but it's still anyone's guess as to the specifics. The GFS this morning has persisted in showing a cyclonic north-westerly type which would bring mostly bright showery conditions with a high incidence of hail, and the UKMO seems to be trending in that direction.

The ECMWF's easterly, on the other hand, would probably bring mostly dry cloudy weather as the continent is relatively warm at this time of year and the North Sea is relatively cool- 850hPa temperatures rise above the -5C mark shortly after its initiation which would support this.

The Easter weekend is currently looking set to be cloudy with average temperatures and some showery light rain, though perhaps more extensive rain on Monday.

[Cheese Rice]

The current projections certainly make a mockery of the CFS charts...

[Cheese Rice]

The ECMWF's easterly, on the other hand, would probably bring mostly dry cloudy weather as the continent is relatively warm at this time of year and the North Sea is relatively cool- 850hPa temperatures rise above the -5C mark shortly after its initiation which would support this

Looking at the ECM easterly 850s are projected at -7/-8

SST's are 6/7.c

A 15.c temperature difference should be enough to create convection, aided by a significantly stronger sun we would see pretty significant showers with thunder, lightning and hail. Further south and East looks more mixed with a mixture of rain sleet and snow under the influence of the low, so really what we saw earlier today but over the South East. While 'up-north' we would see sunshine and persistent wintry/snow showers.

I really hope the ECM is onto something even if the ECM is on the wrong track the GFS still suggest a wintry flavor for the first half of April. Conversely the ECM/UKMO are both similar at T144 while GFS looks at odds with the lows.

Edited April 4, 2012 by Cheese Rice

[Glacier Point]

The current projections certainly make a mockery of the CFS charts...

See version 2:

[Summer Sun]

Yes CFS v2 gives a much better indication with April either average or below, then from May right through to September it stays either just above normal or average but no month see's below average temps

Sadly no months see above average rain in the areas that need it, with next month going back to below average for many

Edited April 4, 2012 by Gavin D

[Costa Del Fal]

I have been following the raw CFS output daily lately and the CFS does appear quite keen on a return to much more settled conditions in May though interspersed with a few wetter spells though quite brief. Of course, with any long range output, especially when produced daily is prone to big swings but trends are the most important thing here. May does look like it could be a mix of the pattern we had in March and what we have now.

Lets take all the rain we can get now. Every little helps even though this is not Tesco. :lol:

Into the Summer is still up in the air at the moment I think and I wouldnt like to place a bet on what the most likely outcome is!

Edited April 4, 2012 by Blizzards

[Cheshire Freeze]

Yes CFS v2 gives a much better indication with April either average or below, then from May right through to September it stays either just above normal or average but no month see's below average temps

Sadly no months see above average rain in the areas that need it, with next month going back to below average for many

Why do I get the feeling that when you say 'sadly' you actually mean gladly. A dry summer will do no-one any good, that is unless you're a cactus.

[Summer Sun]

Why do I get the feeling that when you say 'sadly' you actually mean gladly. A dry summer will do no-one any good, that is unless you're a cactus.

I said sadly because I mean it, as a Gardener myself I know the importance of water

[picog]

Yes CFS v2 gives a much better indication with April either average or below, then from May right through to September it stays either just above normal or average but no month see's below average temps

Sadly no months see above average rain in the areas that need it, with next month going back to below average for many

What is the difference between the usual CFS and CFS v2? Do you have a link please.

Edited April 4, 2012 by picog

[Summer Sun]

What is the difference between the usual CFS and CFS v2? Do you have a link please.

Here is the difference

CFS 1 - Rainfall for May

V2

V2 enables you to click each month rather than as V1 is now, it is also gives a different outlook but how accurate they are remains the big question

[Cheese Rice]

Well I hope for some more dry and sunny weather. We had 15 hours of snowfall today/yesterday which in rain terms is quite alot.

Most of the country is actually doing fine for water levels so I couldn't care less that the water companies in the South East have poor water management.

Besides April looks like it could be quite wet for the south and wintry for the north which should help water levels in the south east.

Edited April 4, 2012 by Cheese Rice

[Cloud 10]

What is the difference between the usual CFS and CFS v2? Do you have a link please.

Climate Prediction Center - Outlooks: CFS Forecast of Seasonal Climate Anomalies

Climate Forecast System

Edited April 4, 2012 by Cloud 10

[Cheshire Freeze]

By 'eck that's a long draw northerly on the GFS at 240 hours. A taste of the Arctic in mid April that would be.

[Thundery wintry showers]

Looking at the ECM easterly 850s are projected at -7/-8

SST's are 6/7.c

A 15.c temperature difference should be enough to create convection, aided by a significantly stronger sun we would see pretty significant showers with thunder, lightning and hail. Further south and East looks more mixed with a mixture of rain sleet and snow under the influence of the low, so really what we saw earlier today but over the South East. While 'up-north' we would see sunshine and persistent wintry/snow showers.

Personally I have doubts- polar continental air is fundamentally very dry and stable, and is rarely conducive to vigorous homegrown convection except during summer heatwaves. The main forcing mechanism for convection would indeed be the cold air flowing over the comparitively warm North Sea, but I think we'd only manage shallow convection from it, particularly with the lack of any pronounced cold pooling at the 500hPa level and high pressure close by. If we were talking a north-easterly sourced well within the Arctic Circle I'd be more inclined to agree, as those airmasses tend to be less stable.

In any case we'd be looking at a maximum of 36 hours for wintry shower potential as the cold 850hPa temperatures soon get mixed out from the east.

The GFS meanwhile is sticking with a showery north-westerly- I'm sure the GFS scenario with its unstable polar maritime air would lead to vigorous convection with widespread hail and possible thunder for some.

[Cheshire Freeze]

Personally I have doubts- polar continental air is fundamentally very dry and stable, and is rarely conducive to vigorous homegrown convection except during summer heatwaves. The main forcing mechanism for convection would indeed be the cold air flowing over the comparitively warm North Sea, but I think we'd only manage shallow convection from it, particularly with the lack of any pronounced cold pooling at the 500hPa level and high pressure close by. If we were talking a north-easterly sourced well within the Arctic Circle I'd be more inclined to agree, as those airmasses tend to be less stable.

In any case we'd be looking at a maximum of 36 hours for wintry shower potential as the cold 850hPa temperatures soon get mixed out from the east.

The GFS meanwhile is sticking with a showery north-westerly- I'm sure the GFS scenario with its unstable polar maritime air would lead to vigorous convection with widespread hail and possible thunder for some.

Aye. If the projected synoptics get any more 'get up and go' in relativity to the past ? months I'll be needing an oxygen mask and a lie down in a darkened room.

[Polar Maritime]

Some very cold charts tonight throught the GFS run.

[Summer Sun]

Some very cold charts tonight throught the GFS run.

Yes we are certainly into a different pattern now after basking in the March sunshine this is now pay back time, still best get it out the way now hopefully we'll get sufficant rain to enable us to have a decent summer with-out been plagued by drought's

[Strider]

Dream winter charts from all models... just 3 months too late! Looks like temperatures could continue generally below average for quite a way into April.

[Summer Sun]

ECM continues the unsettled theme tonight plenty of rain around with the chance of some strong winds on Bank Holiday Monday

http://www.null/ds/ecm.htm

Precipitation looks ok to the 20th, though the percentages look to be around 100% of normal Precipitation for most of england and wales with parts of the SW around 75%

[damianslaw]

Some cold looking charts on offer this evening.

All models agree short term for a weak northerly drift over the weekend with weak frontal activity from the NW bringing light rain or showers especially for the NW with temps here remaining slightly below average, average temps further south but certainly nothing particularly mild on the horizon thanks in part to lots of cloud. It does look a preety woeful easter period for sunshine.. preety uninspiring it has to be said.

All models then agree on low pressure moving down from the NW with associated trough - this becoming a very active feature early next week bringing a period of slow moving heavy rain and cold conditions generally to places north of the trough i.e. scotland/n england.

UKMO suggests this feature could become very slow moving and gradually fill in situ.

ECM and GFS suggest the feature will track SE ushering in a cold NW then Northerly blast. GFS showing a very cold arctic blast for next weekend - its a long way off, but if it came off, it would bring convection galore with heavy snow showers to the north espcially where any troughs form..

Certainly a very unsettled outlook for the foreseeable future, generally cold for the north with average temps in the south little sunshine and the potential for some heavy rain and possibly more snow in the north as we move through next week. A complete contrast to conditions since mid feb.