Model Output Discussion

[Gordon]

Zero is my favorite number

[RichardR]

because all previous gfs runs HAVE been the type of charts that would lead to 'negetive' comments, showing cool, changable, wet weather...

Way out in fantasy land, of course. There's till no reason for people to get "negative" about a little bit of low pressure for a few days IMO. This ain't the Costa Del Sol.

[snowlover2009]

just my feeling but i think june could be one of the best summer months since the pre wet summers. thundery next week and potentially staying quite mild indeed. and 06z brings in a plume from the first world cup match on sat 12th june, and i am loving those 06z ensembles indeed!!!!!!!

i can imagine many people who are worried about a wet summer and a deluge are looking at next weeks charting and praying they dont happen, but theoretically it won't be as bad as the models indicate IMO. the charts look extremely wet because the whole of the uk is at risk of thunder and heavy showers next week, which is why the gfs has lots of the country under rain as well as the continent, but as the days go on the risk of showers increase, so don't expect the whole of each day to be wet all day, just at odd points of the day, particularly later in the day.

so

Edited June 3, 2010 by snowlover2009

[Geordiesnow]

Sunday's breakdown still looks fairly interesting, certainly a chance of the weekend ending with a bang which is normally the case in these warm spells hence the term 3 days followed by a thunderstorm.

Next week looks cooler with temperatures back down to average, considering people were worried by the lack of rain, i thought the charts would be more welcoming on here. Hopefully any rainfall will be the convective kind and not frontal rainfall thus at least there should be sunshine in between the showers.

[RichardR]

I haven't noticed any CAPE on the storm risk thing on this site for my area at all saturday-sunday but I'm assuming that's only measuring surface CAPE whereas this stuff is likely to be elevated and won't show up on there.

[SP1986]

It will most likely be the upper levels of the atmosphere that gets the instability, the same as this time last year. The cooling, dryer upper atmosphere and the warmer, moisture laden lower atmosphere should cause a few fireworks somewhere.

[Harry]

Sunday's breakdown still looks fairly interesting, certainly a chance of the weekend ending with a bang which is normally the case in these warm spells hence the term 3 days followed by a thunderstorm.

Next week looks cooler with temperatures back down to average, considering people were worried by the lack of rain, i thought the charts would be more welcoming on here. Hopefully any rainfall will be the convective kind and not frontal rainfall thus at least there should be sunshine in between the showers.

If people are worried about not having rain then surely they don't want convective stuff? Showers in this kind of scenario (unless very frequent) are relatively pointless. Hard ground will mean a lot of run off into drains and such like, the sun emerging directly after will mean a lot of it will evaporate, and the trees being in peak leaf will mean a lot of evapo-transpiration.

I think if people are truly concerned about lack of rain, then a lengthy spell of persistent wet weather (not necessarily heavy) will be required.

In terms of thundery potential, there's still a bit too much uncertainty. We are on what appears to be a knife edge in this respect - a plume of moist air MAY advect over us hence enhancing the risk of thundery weather, however the slightest disalignment of the LP to our W could keep it over the continent, while we keep relatively warm and moist air here. GFS is playing the continental card (as it loves to do) while MetO earlier was thinking the contrary.

In relation to another post, where did the MetO say a moderate risk of thundery weather for Northern and Midland areas? Unless they issue a watch, that's not normally a term they use, especially in regards to convective weather (lets remember, the MetO may by and large be very good, but IMO they are pants with forecast thundery weather)

Edited June 3, 2010 by Harry

[SP1986]

Most likely because thundery weather is quite rare in this country anyway to any great degree.

[The PIT]

No 12 oz GFS ????

[Paceyboy]

No 12z UKMO either?

[mushymanrob]

Way out in fantasy land, of course. There's till no reason for people to get "negative" about a little bit of low pressure for a few days IMO. This ain't the Costa Del Sol.

... but its model discussion, we know its fi , but fi is where the trends often start. we know it might not happen as per run, but if its predicting a miserable outlook then commenting on it is well within the perameters of this forums purpose!

or should we just totally ignore fi and only comment on upto t120?

what do you mean no 12z?... its there... and they dont make good viewing if its sun and warmth your after. the big three all have a general theme of high to our west and north, low to the south/near continent, winds from anywhere from north to east... theres still scope though for optimism, this has to be the best start to summer for some time, and the predicted synoptics arnt that far from producing something warm and sunny.

[rmc1987]

... but its model discussion, we know its fi , but fi is where the trends often start. we know it might not happen as per run, but if its predicting a miserable outlook then commenting on it is well within the perameters of this forums purpose!

or should we just totally ignore fi and only comment on upto t120?

what do you mean no 12z?... its there... and they dont make good viewing if its sun and warmth your after. the big three all have a general theme of high to our west and north, low to the south/near continent, winds from anywhere from north to east... theres still scope though for optimism, this has to be the best start to summer for some time, and the predicted synoptics arnt that far from producing something warm and sunny.

Well late in FI looks warm with high 850's after a week of cooler/wetter weather! The more unsettled weather would probably continue though as it's just one run. The outlook has been hinting at more unsettled weather for a good while lately.

[Thundery wintry showers]

Interestingly GFS 12Z in the outer reaches of FI (post T+216) shows the kind of mid-Atlantic ridge scenario that Glacier Point's previous teleconnections analysis suggested. It's worth keeping an eye on that possibility developing, though we still have a good week or so of sunshine followed by showers/thunderstorms before it arises.

[Kentish Kiwi]

what do you mean no 12z?... its there... and they dont make good viewing if its sun and warmth your after. the big three all have a general theme of high to our west and north, low to the south/near continent, winds from anywhere from north to east... theres still scope though for optimism, this has to be the best start to summer for some time, and the predicted synoptics arnt that far from producing something warm and sunny.

Its certainly not on the Netweather model viewer/reader, which is what the above posters were referring to.

Also, in my opinion, last year was a much better start to the summer, with May also having been particularly nice.

[RichardR]

... but its model discussion, we know its fi , but fi is where the trends often start. we know it might not happen as per run, but if its predicting a miserable outlook then commenting on it is well within the perameters of this forums purpose!

Nothing wrong with looking out for trends but the question is who said low pressure = miserable though? Why does low pressure/rain have to be seen as inherently "miserable"? "Cooler", or "wetter" is good enough.

what do you mean no 12z?... its there... and they dont make good viewing if its sun and warmth your after. the big three all have a general theme of high to our west and north, low to the south/near continent, winds from anywhere from north to east... theres still scope though for optimism, this has to be the best start to summer for some time, and the predicted synoptics arnt that far from producing something warm and sunny.

I said nothing about "no 12z". Somebody else said that.

Edit: Acutally it's just on this website that the GFS based forecast hasn't updated since the 00Z. On the proper website for it www.wetterzentrale.de the 12z is all there.

Edited June 3, 2010 by RichardR

[William of Walworth]

Nothing wrong with looking out for trends but the question is who said low pressure = miserable though? Why does low pressure/rain have to be seen as inherently "miserable"? "Cooler", or "wetter" is good enough.

It is if you're hoping for plenty of outdoor summer activity (just at random example, if you're going to Glastonbury! ) and if LP dominates in late June (20th onwards especially).

LP and rain would usually then mean MUD down Somerset way!

But currently there seems to be at least some scope/hope that more HP influenced conditions MAY yet return in FI. All still to play for IMO with current models and trends.

My main wish for this summer as a whole (not just late June! ) is that the Atlantic plays much less of a role than in recent summers, and that we see far less talk this year of the dreaded Southerly Tracking Jet and asociated long rains of deep Lows, they're called 'depressions' for a reason ...

Edited June 3, 2010 by William of Walworth

[mushymanrob]

Also, in my opinion, last year was a much better start to the summer, with May also having been particularly nice.

its been a few years since we had 2 'hot' spells by june 3rd.. in 07 i had to wait until august for a 25c, then it was breeched only 3 times. but the mean temp might be lower then previous mays thanks to the cold start.

I said nothing about "no 12z". Somebody else said that.

i know, i wasnt refering to you there (hence the new paragraph)

[RichardR]

It is if you're hoping for plenty of outdoor summer activity (just at random example, if you're going to Glastonbury! ) and if LP dominates in late June (20th onwards especially).

LP and rain would usually then mean MUD down Somerset way!

But currently there seems to be at least some scope/hope that more HP influenced conditions MAY yet return in FI. All still to play for IMO with current models and trends.

My main wish for this summer as a whole (not just late June! ) is that the Atlantic plays much less of a role than in recent summers, and that we see far less talk this year of the dreaded Southerly Tracking Jet and asociated long rains of deep Lows, they're called 'depressions' for a reason ...

Yes "depressions" because the air pressure is low.

I'm just trying to hold a balanced view, that's it

High pressure like today's weather with sun and comfortable temperatures is lovely and sure it would be nice for an outdoor concert too however that's not the only thing is it? Gardeners etc... need rain for the plants as you know (though there are such things as watering cans and hose pipes LOL) but let's just be balanced about it. All the weather we get here has its place so why worry about it. No point. If the summer does turn out to have a lot of Atlantic influence what are you going to do about it anyway?

Edited June 3, 2010 by RichardR

[mushymanrob]

If the summer does turn out to have a lot of Atlantic influence what are you going to do about it anyway?

moan ! it always helps!

[The PIT]

Well I found a rare working GFS 12 oz and it looks rather unsettled and wet after this weekend. ECM also gone walkies as well which is a pity as it would be nice to compair.

[The PIT]

Link to ECMWF 12 run:

Wetterzentrale ECMWF

Although turning unsettled after the weekend, the outlook looks a showery one during the first half of next week. Three main models agreing on slack area of low pressure approaching from the west to be situated over or near UK during Tuesday to Wednesday period. So potential for showers and weak thunderstorms across southern part of the UK (at this time) given daytime heating under cold pool aloft and slack windflow. Beyond this, ECMWF progresses the low further east to allow a cool north to northeast flow, while pressure tries to build once again from the south-west.

Thanks this it loaded up. Last time I tired it timed out.

Not sure about the ECM it certainly moves the low east then north west and really deepens it. Just seems a little strange.

[rmc1987]

Well I have to say after looking at the GFS I was left feeling a bit optimistic as out in FI it was showing some warmth again. On here though it sounds like this may be false with cool and unsettled weather being the actual case. The 850's looked high which would give us decent temperatures. I thought it was some sort of trend for a cool down this weekend with unsettled weather for a week then warming up again or atleast possibly.

Edited June 3, 2010 by rmc1987

[SP1986]

The ECM has certainly backed away from the mild, humid weather that it was showing this degrading storm chances along with humidity. You can only hope it's an outlier in mid-term but somehow when models change as such it's difficult to doubt it's setting a trend which in this case is as far removed from even average summery as you could probably get. Of course that doesn't mean itll be correct.

[Thundery wintry showers]

Up until midweek next week it still looks humid & thundery for the most part, at least south of the Scottish border- the main change is after that, with GFS and now ECMWF hinting at the development of a mid Atlantic ridge scenario with northerly winds over the British Isles, a solution supported by the teleconnections from a fair while ago, so I think it represents the most likely evolution.

RichardR is right about the use of "depression" for low pressure- it isn't referring to good or bad weather, but rather "depression" is a general term to describe an area of low values surrounded by areas of relatively high values- in this case air pressure. Low pressure usually means a higher chance of rain than high pressure, but the association with temperatures and sunshine amounts is less clear-cut- a slack thundery type low might give relatively warm sunny weather, while a stream of Atlantic lows usually means cool cloudy weather in a nutshell.

For instance some people might see a chart like this and think "dull, cold, rain, miserable":

http://www.wetterzentrale.de/archive/ra/1995/Rrea00119950715.gif

...when in fact in Tyneside this was a sunny day with a couple of thunderstorms in the evening and a high of 21C. But that depression had hardly any frontal activity associated with it- add fronts to the mix and dull cool & wet is usually the outcome.

[Derp Patrol]

A good 18Z run.. typical summer weather really, a slight cool down at the start of the week for a few days (but it will never really get cool), with the high pressure building back on Thursday and taking control for the remainder of the run in southern areas, but northern areas might not do so well. This was also shown on the 12z GFS so a trend may be starting.