Model Output Discussion

[ANYWEATHER]

You will see the difference from four charts ,two from ecm and two from gfs t144 and t168 respectively ummmgh?

[Pennine Ten Foot Drifts]

Yes but ECM immediately follows with this

so although there is some variation both main models are in broad agreement that we are heading into a much more 'summery' period of weather

[johnholmes]

I think it is becoming increasingly unlikely that from about 10th August onwards the Atlantic will still be dominant.

In its place, as all 3 major hemi sphere models continue to show on their 500mb anomaly charts, a spell of anticyclonic weather is going to occur.

How long is difficult to judge but I would suggest 7 days perhaps longer.

The high moving in from the WSW and the upper wave length looks right for it to continue to move about ENE.

Not necessarily B-B-Q weather at first but probably not bad as time goes on. How much heat will depend on

1-its actual position after the first few days

2-the upper wave length which will govern how soon, or how long, it is before the next upper trough moves in from the west.

[mushymanrob]

hmm..im not so enamoured with this mornings runs, all of which appear to downgrade any highpressure/settled spell. the gfs shifts towards yesterdays ecm which was more unsettled. tbh i cant really see any decent warmth in this mornings outputs, hints maybe, but nothing strong.

its looking like after a very wet july , summer will just gently slip away quietly through the rest of august.

[johnholmes]

hmm..im not so enamoured with this mornings runs, all of which appear to downgrade any highpressure/settled spell. the gfs shifts towards yesterdays ecm which was more unsettled. tbh i cant really see any decent warmth in this mornings outputs, hints maybe, but nothing strong.

its looking like after a very wet july , summer will just gently slip away quietly through the rest of august.

oh ye of little faith!

[ANYWEATHER]

The cfs, shows the jet stream pushing over the northern half of the uk amd slipping down the eastern areas of England, a trend perhaps of at least more settled weather for at least the southwestern half of the uk ie south Wales, southwest England and central and south/southeastern England as the azores hogh tries to make an influence! Perhaps not perfect late Summer weather coming up but at least a little better for Summer activities in the "great outdooors!"

[Thundery wintry showers]

I'd take cloudy dry and warm over sunshine and downpours, but we may get reasonable sunshine amounts at the w/e anyway.

Ironically this weekend looks like being closer to the latter scenario- though the showers will be somewhat more isolated than we were used to for much of July, so I expect most places to stay dry.

The next couple of days look interesting with plenty of dry sunny weather in the north and west and chances of thunderstorms towards the southeast, running up the remains of that old cold front that produced a cloudy wet day for many parts yesterday. After that there continues to be a lot of divergence between ECMWF and GFS with neither really backing down at this stage. The ECMWF doesn't really inspire confidence if it's warm dry sunny weather you're after, as the low pressure systems continue to come in from the west, but the GFS scenario would promise a good few days to a week of dry sunny weather. Noteworthy is that the Azores ridge gets further and further north with successive GFS runs, so perhaps the GFS is onto something here.

[mushymanrob]

oh ye of little faith!

i dont believe in faith john, i believe in bad luck!

well the 06z is back to painting a better picture then the 00z did, and the ensembles for (me) derbyshire would tend to back the 06z with higher pressure over the next week or so. the 06z even throws in a couple of possible mini heatwaves as a high pressure centre drifts east allowing warm southerlies for a short time. could things develop into something longer lasting and hot?... well at least the building blocks are getting into position, so perhaps...but im not expecting it...lol..

[Frosty.]

summer will just gently slip away quietly through the rest of august. :lol:

I must be looking at different charts to you then mushy...the outlook suggests to me a strong belt of high pressure as the Azores high and an anticyclone over the Baltic link up after the weekend across the southern half of britain at least. Scotland looks more mixed with low pressure to the north west / north of scotland bringing damp & breezy conditions to the far north but the southern half of scotland should be brighter and warmer at times. It then looks like the high could transfer to the east of the uk and allow a hot SE'ly flow just after mid August but the GFS 06z is hinting at some much more unsettled and cooler conditions towards the end of August but too far ahead to be of any concern.

[Methuselah]

I must be looking at different charts to you then mushy...the outlook suggests to me a strong belt of high pressure as the Azores high and an anticyclone over the Baltic link up after the weekend across the southern half of britain at least. Scotland looks more mixed with low pressure to the north west / north of scotland bringing damp & breezy conditions to the far north but the southern half of scotland should be brighter and warmer at times. It then looks like the high could transfer to the east of the uk and allow a hot SE'ly flow just after mid August but the GFS 06z is hinting at some much more unsettled and cooler conditions towards the end of August but too far ahead to be of any concern.

Either you're absolutely right, Frosty; or it's that old Tottenham Hotspur this is the year! optimism that's speaking? Either way mate, I'm with you! :lol:

[Frosty.]

Either you're absolutely right, Frosty; or it's that old Tottenham Hotspur this is the year! optimism that's speaking? Either way mate, I'm with you!

It's a bit of both :lol:

It looks very good for southern britain for much of the next few weeks once the thundery rain threat has cleared away from the south east later this week. High pressure looks like dominating in the south and maybe the whole of the uk by the end of next week or early the following week.

[mushymanrob]

I must be looking at different charts to you then mushy...the outlook suggests to me a strong belt of high pressure as the Azores high and an anticyclone over the Baltic link up after the weekend across the southern half of britain at least.

that was written after perusing the 00z, which was much worse then the 06z and more like the ecm which when i last looked, wasnt as 'high-centric' as the gfs.

edit...just seen the ecm, which does look much more atlantic/mobile then the 06z gfs suggests.

Edited August 5, 2009 by mushymanrob

[Thundery wintry showers]

Hmm... looks like Mushymanrob's pessimism may be entirely justified here. The GEFS ensembles strongly suggest that the GFS control was a bit of an outlier with positioning the Azores ridge right over Britain:

http://www.netweather.tv/index.cgi?action=ensviewer;type=panel;

Most of them go for a westerly pattern like the ECMWF. So I have to lower my confidence on a few days to a week of dry sunny weather, perhaps down to around 30% chance.

[Shiny_Bottom_1]

Interestingly though Ian, the ensembles still paint quite a dry picture, albeit less warm (still low 20's in Central England) and perhaps sunny.

All is not lost, and we may be seeing the usual too'ing and fro'ing of the models before a decision is made.

Certainly hints at something more akin to what many have been looking for on recent days runs, but the movement in projection would suggest perhaps whilst the warmer weather is now a little downgraded, then same philosophy would apply for the 06z.

[Frosty.]

Hmm... looks like Mushymanrob's pessimism may be entirely justified here. The GEFS ensembles strongly suggest that the GFS control was a bit of an outlier with positioning the Azores ridge right over Britain:

http://www.netweather.tv/index.cgi?action=ensviewer;type=panel;

Most of them go for a westerly pattern like the ECMWF. So I have to lower my confidence on a few days to a week of dry sunny weather, perhaps down to around 30% chance.

The latest meto update is similar in tone to what the GFS 06z shows with warm/v.warm bright conditions in the south and more unsettled in the north but fair at times even up there despite what the GEFS ensembles indicate.

[Iceberg]

It still looks pretty nailed for a warm, dry August down here in Dorset, perfect if anybody is planning a last min holiday ! :lol: or even a BBQ.

Avg pressure stays above 1020mb for the entire run, Precip minimal and max daytime temps anywhere from a pleasent 20C to a very warm 27C.

Shame really that I am going upto Lincolnshire for my holiday in just over weeks time.....[idiot]

[mushymanrob]

my pessimism is based on current track records. ever since the heat went 5 weeks ago there have been promises of a return to someting nice 'next week'.... trouble is, it remains in 'next week' . i think that weather acts in patterns, for 'x' amount of time before something else takes over. the manner in which the current weather is behaving doesnt make me think that anything 'better' is going to ensue.

just look at current conditions.... the gfs first picked this up last week and suggested we were in for something more summery...even though it would be brief. then this troublesome front kind of ended that suggestion and replaced it with ... 'azores ridging in afterwards', indeed by now im supposed to be in sunny dry conditions... now the latest is that this troublesome front is not going to clear properly until friday, with huge amounts of rainfall for eastern areas tomorrow...

time after time every glimmer of hope for 'summer' gets downgraded, so just because the gfs 06z is a summery run, ill not believe it until it happens. the trend is for unsettled weather to dominate.

i hope my pessimism is misplaced, but tbh its usually more often then not... proven correct. :lol: dont forget, no one more then me would like to see a heatwave, so my pessimism goes against my wishes.

[Shiny_Bottom_1]

Hi Rob.

I think the main difference is the recent projections in the ppn.

Recent weeks have continued with the wet theme, albeit with some potential of warmer weather at some point (so understand where your coming from).

I think in general, we might need to look at it as building blocks. A drier outcome I think would be welcomed by most (and would guess yourself also), and any 'extra' heat would be an added bonus :lol:

[Rob]

the weather looks to be settled once again next week with some good opportunites for some dry and very warm weather! Brilliant.

[Jezzer]

I'll be keeping everything crossed, this developing High was suggested last week, just hope it sticks around for when I head to the South coast on the 16th and 17th August. Would make my day if it did!

[Thundery wintry showers]

Lack of ppn is a start, but it's worth noting if we have a few wet, relatively cloudy weeks, then a dry but very cloudy week, and then a return to the fairly cloudy and wet weather- like in August & early September last year- then although some will see the dull dry week as bliss, most won't be too impressed. However one major difference is that it looks unlikely that the UK will stay stuck in tropical maritime air on the high's northern flank. At the very least, even if the high ends up too far south to bring widespread dry sunny calm weather, there should be polar maritime incursions bringing dry weather with sunny intervals.

I am cautiously optimistic for a shift towards something more "summery" this month, but only cautiously, especially as far as northern Britain is concerned.

[Costa Del Fal]

I think next week is begining to look very nice for here and the rest of the southern half of the UK. Further North doesnt look too bad either except the higher risk of rain/showers at times.

[Cheese Rice]

Looks like more rain to come for most of eastern england over Friday and into Saturday http://cirrus.netweather.tv/gfsimages/gfs.20090805/12/39/ukprec.png . Meto warning out as well for up to 50mm on Thursday and 30mm on Friday which in some places may give 80mm of rain which may give some flooding.

[The PIT]

Looks like more rain to come for most of eastern england over Friday and into Saturday http://cirrus.netweather.tv/gfsimages/gfs.20090805/12/39/ukprec.png . Meto warning out as well for up to 50mm on Thursday and 30mm on Friday which in some places may give 80mm of rain which may give some flooding.

And err Thursday as well. Could be an interesting end too my Holiday. T storms will do nicely. After that settled looking and mostly dry. Of course this will mean if it happens the media will take the met office apart again for suggesting a wet August.

[Lincs Observation]

It still looks pretty nailed for a warm, dry August down here in Dorset, perfect if anybody is planning a last min holiday ! or even a BBQ.

Avg pressure stays above 1020mb for the entire run, Precip minimal and max daytime temps anywhere from a pleasent 20C to a very warm 27C.

Shame really that I am going upto Lincolnshire for my holiday in just over weeks time.....[idiot]

Whats wrong with Lincolnshire, on the whole its been ok up here, however when its rained it bloody rained.

looks like next week could be ok up here, well better than it has been anyway.

LO

Edited August 5, 2009 by Lincs Observation