Nice start to October.

http://www.wetterzentrale.de/pics/Rtavn3241.png

Good morning everyone. Here is the report on the midnight outputs from GFS, UKMO, GEM, NAVGEM and ECM for today Thursday September 19th 2013.

All models show a system of troughs crossing steadily East over the UK in association with a Low pressure area swinging east to the North of the UK. All areas will see a spell of rain today followed by dry and fine weather this evening tonight as pressure rises. Tomorrow will be a dry and bright day with a weak ridge crossing the UK slowly through the day with some bright sunny spells and respectable temperatures. Over Saturday pressure will of risen well but a warm front will be crossing NE across the UK with a lot of cloud in the South and thick cloud to northern and Western areas with rain and drizzle in places. It will feel increasingly warm and humid. Then from Sunday and into the start of next week drier air is shown to filter North across the UK in association with High pressure just to the East of Britain with cloud breaking and sunny spells developing and it will become warm in the South and East but with the risk of fog at night increasing.

GFS then shows cloud in the far NW finally breaking up while transferring to NE coasts as a new High builds in from off the Atlantic. This drags some cooler uppers across the East of the UK with cloud amounts larger it will feel rather cooler for a time here with the best of the brightness and daytime warmth likely towards the West. High pressure is then shown to dominate over the UK for the remainder of the run but of a much colder variety with rather chilly air over the UK, pleasant enough in daytime sunshine but jolly chilly and potentially foggy conditions overnight slow to clear in the morning's.

UKMO today shows things rather warm and dry to start next week with High pressure well established over the UK giving all areas even the NW by then some decent dry and bright weather with temperatures above average by day with mist and fog patches overnight.

GEM is a little like GFS this morning with the precursor to building High pressure in off the Atlantic allowing a chilly NW feed to drag cooler uppers across Britain through next week meaning after a warm start temperatures will fall back but the weather remain largely the same with dry and bright days with cool nights with fog patches. Late in the run pressure leaks away as the High pressure slips SE into the Continent with Atlantic fronts and SW winds bringing the threat of rain into the UK from the SW by the end of the run.

NAVGEM shows High pressure across the UK early next week being squeezed into a ridge by late in the week. After a warm start it looks like temperatures will decline later in the week as cooler uppers get drawn in. Nevertheless, fine weather holds on for most with sunshine by day and cool, misty nights with little if any rain likely for most next week.

ECM looks a little like GEM this morning pulling High pressure away SE later next week and allowing unsettled and rainy conditions to replace it soon after midweek as fronts cross NE as the High declines SE into europe. The potential is there for much colder conditions to arrive at the tail end of next week and through the weekend as cold air arrives from the North.

The GFS Ensembles are firming up on showing the cool down as described above in one form or another following several warm and settled days early next week. There are some very cool options on the table with some members also introducing Low pressure and rain into the mix towards the end of the output.

The Jet Stream shows the flow moving North of the British mainland over the coming days where it is maintained for a time. Later next week it shows signs of moving South over the UK again in response to High pressure declining away from the UK. The end part of the run is very undecided with pockets of flow shown at various latitude with some suggestion it may end up South of the UK but this is very speculative at this range.

In Summary this morning the fine spell is still well and truly on the way though with subtle differences coming to light this morning. In the first half of next week things look clear cut as it will simple become dry, bright and reasonably warm for most of not all of Britain with a fog risk at night. Thereafter subtle movements in the high pressure could mean the Uk engages colder air into the circulation as the cold surge in northern Europe becomes perilously close to the East on some output. Other output such as GEM and ECM shows a seepage of warmth too but this time as Atlantic low pressure feeds over a declining High pressure moving SE into Europe resulting in a return to cooler and unsettled conditions late next week. ECM goes one step further with a particularly chilly looking 10 day chart with rain on a vigorous cold front slipping SE would be followed by a marked drop in temperature with potentially wintry showers over Northern hills and frost at night in the days that follow. So enjoy the warmth and sunshine early in the week because it might not last too long after midweek.

Just goes to show what a difference one run can make - start of October looking the opposite on this chart today:

http://www.meteociel.fr/modeles/ecmwf.php?ech=240&mode=1&map=0&archive=0

No surprise really. The start of October is well beyond the 'guess range' at 10 days +.

People pouring over every CFS chart for next February take note LOL.

Aye! Place ya bets which horse will come in first?

0z gfs opp was wild for cold >25th http://www.jp2webdesign.co.uk/two/ensembles/

Mean looks a good week for the south at least touch wood.

http://www.meteociel.fr/modeles/gefs_cartes.php?code=21&ech=126&mode=0&carte=0

OT, and it really looks pretty decent from the weekend into next week for many, although the far NW will be brushed by the Atlantic at times.
Of interest long-term is the first of the 'cool downs' across Eurasia extending into Finland next week with the first significant snow here.

Hi all,

Here's today video update;

An Uncertain End To September;

http://www.gavsweathervids.com/

I think temperatures will be cooling off quite a bit after the warm start to next week.

Cheers Gav

http://www.wetterzentrale.de/pics/Rtavn2881.png

October looks to start on a chilly Autumnal note

http://www.wetterzentrale.de/pics/Rtavn28817.png

I don't usually pay too much attention that far ahead but as I'm in Scotland for a couple of weeks then I'm watching the runs.

Based on the fact that GFS is 'good' at flagging up northerlies and this mornings ECM is dabbling with similar at 240, need to dig out the thermals just in case.

http://images.meteociel.fr/im/21/ECM1-240_cpb3.GIF

Good evening. Here is the report on the 12 midday output of GFS, UKMO, GEM, NAVGEM and ECM for today Thursday September 19th 2013.

All models show the pattern that's been shown for days now in that the last rain for a time has recently cleared SE England leading to steadily rising pressure from now on from the South and SW. A ridge crosses East tomorrow with dry and fine weather for most in a light to moderate Westerly breeze with sunshine and passing clouds and temperatures around average. By Saturday a warm front will be moving NE across Northern and Western Britain carryng a lot of cloud and some drizzly rain in places for a time before drier air reaches the SE later and works it's way further North across the UK on Sunday and Monday. It's from that point on that the pattern between the models diverge.

GFS shows High pressure declining away slowly SE through the week with pleasant weather remaining intact for most of Britain for quite a while. Late in the week pressure will of fallen sufficiently to allow fronts to push in from the West and SW with rain a risk for many next weekend as temperatures fall. Then through the rest of the run Low pressure areas from the SW then North come into play for the UK with an ever cooling air mass covering the UK to bring very cool and unsettled conditions to end the run.

UKMO shows High pressure over the top of the UK next Wednesday with sunny and warm daytime weather with clear, cool and potentially foggy nights.

GEM shows pressure falling after midweek with the UK declining away as fronts push up from the SW with some rain and cooler conditions reaching many areas over the weekend.

ECM tonight shows a large High having developed South of Iceland next Tuesday absorbing our weekend High into a ridge early next week. After a few warm days temperatures would likely steadily fall back to average levels with night's cool and misty with some radiation fog formation under light winds. Later in the week things show signs of turning more unsettled as pressure falls and Low pressure develops to the SW and with a cold feed not far to the NE with rain likely for many next weekend in much cooler air.

The GFS Ensembles show good support for a warm period over the weekend and start of next week before cooler conditions look like developing as well as more unsettled conditions with rain at times from the 27th in the South. The North show a rapid cool off earlier than further South with a huge spread between members from as early as midweek next week.

The Jet Stream shows the flow migrating North of the UK over the next few days with a cut off circulation down to the SW. As this small feature expands it draws down the SW to NE flow more and more SE on its trajectory through the UK so that indications are shown tonight of the flow perhaps moving South of the UK in the outer limits of the run.

In Summary the weather shows two phases tonight. the first phase will occur between now and Tuesday when gradually warmer conditions are likely to develop with some warm daytime sunshine with cool and misty nights. The second phase is from Tuesday onwards when indications are that High pressure will re-position or decline sufficiently enough to allow lowering temperatures, cloudier and eventually more unsettled conditions to develop across the UK as a whole. It is too early to say whether this trend will be maintained or dropped over the coming days but there are growing indications that the fine and warm conditions that looked like lasting some considerable time a few days ago may be a rather shorter spell than we might of hoped.

Another eye-rolling period of model disagreement is upon us!

Next week Tuesday-Friday, GFS delivers maximums into the 20's for many of us and minimums close to the mid-teens. That's a considerably warm week for late September.

ECM, on the other hand, has much fresher air which would probably see minimums in single digits and maximums struggling to reach the high teens.

Then there's UKMO, which seems to merge the HP to the NW and SE together into one cell, while keeping the warm air in place thanks to a broad trough near the Azores. I guess that scenario would deliver highs into the 20's and lows of 8-12°C (as the airflow becomes very slack). GEM is almost identical on day 6 and has 16°C 850hPa temps brushing the far south. It also keeps the HP to the east in control right out to day 10.

Overall, the warmer option is favoured by the op runs and also by GEFS, with ECM the elephant in the room. Those seriously chilly GEFS members sure are making me nervous though! I won't mind so much if such runs start verifying in October though

http://www.meteociel.fr/modeles/geme_cartes.php?&ech=102&mode=1&carte=0

Indeed James very warm uppers on that gm run for quite a period for south

Thanks Martin

ECM is looking like it wants to develop some early cold scandi blocking. The -5C uppers are shown trying to get pretty close to the UK again by 240h. However we are also going to get a spell of summer, which is pretty much assured. Still, expect all seasons in the next few weeks. 

look at that effort from the beast if only for us cold weather fans

http://www.meteociel.fr/modeles/navgeme_cartes.php?&ech=126&mode=0&carte=0

Amazing that is - that has repurcussions I think for later on in the autumn.

Hi Matty. Is there any way in which a system could be implemented whereby pictures are cropped down to a smaller size upon posting or even attached as a thumbnail. I think pictures/charts serve to appeal visually to the reader and also serve to embelish what the poster has to say.

I understand it is a copyright issue, rather than a presentational one.

Click on the link surely

As MM says it is a copyright issue