Model Output Discussion

[Eugene]

UK Outlook for Sunday 11 Apr 2010 to Tuesday 20 Apr 2010:

A good deal of dry and settled weather is expected throughout the period, with the best of any clear or sunny spells in northwestern areas. Central and eastern parts are likely to see more cloud, with perhaps a few light showers at first, and then there is an increasing risk of cloud and rain spreading from the south towards the middle of the week. Strong winds are likely at times in the far south and southeast. At the start of the week, temperatures should be near normal for many areas, although a little below in the east and southeast, particularly near exposed coasts. However, temperatures are likely to fall below normal generally later in the period.

Updated: 1219 on Tue 6 Apr 2010

Rather strange UKMO update here saying a good deal of dry and settled weather but then saying turning more unsettled towards mid week so not much settled weather then and if its going to be cloudy with a cool easterly to begin with not actually that good either.

Not that great of an update with slightly below in the east and southeast with a strong easterly wind then turning below normal generally, looks like a brief settled warm ish by day(cold at night) snap end of this week unfortunately nothing more.

[cold snap]

Nice to see Warmer weather being shown on the models however i do beleive we will have a coldish spell later is the period.

GFS and ECM at several stages have decided not to completly throw in the towel wth regards to something coldish again.but it is in F1.

So the outlook seams to be very mild if not warm possibly cold later as things stand

[johnholmes]

Well, those of you on the eastern side of the country, IF GFS is correct, and like myself and Bottesford, detest winds off the North Sea-make the most of the latter part of this week before the dreaded winds come in off the North Sea!

GFS even has a suggestion on one day at least of the 'green' values creeping all the way along the Forth-Clyde valley. That is not bad, assuming its correct, for a model programmed x thousand miles away. It does show that modelling is pretty clever at times in spite of the stick models get from most of us at times.

[Frosty.]

Whilst the GFS continues to flip flop in FI despite generally high pressure, northern britain could be most favoured during next week with the lightest winds and most sunshine whereas central and southern britain look like pulling in a cooler and cloudier E'ly which will feel quite roar and unpleasant should it transpire, the 12z thinks about an Arctic plunge in FI but then gets cold feet, unlike the 6z which was rather bullish about the idea, overall, an increasingly settled outlook with pleasant spells of sunshine initially but then the best weather transferring to NW Britain later.

[Thundery wintry showers]

A pretty dull cold outlook from the GFS from T+144 onwards for eastern and central areas of England, but again it's upwards of 6 days out so it may not necessarily come off as shown. UKMO at T+144 has the high pressure further south which results in the easterly shooting off into the continent.

As is often the case we'll need to see which way ECMWF goes.

In the meantime highs of 17-18C are feasible in the W and S on Friday.

[johnholmes]

both EC and Met at T+144 have a lighter flow from an easterly point so I'd prefer their version to that from GFS please.

[The PIT]

both EC and Met at T+144 have a lighter flow from an easterly point so I'd prefer their version to that from GFS please.

Even better if they changed the winds to SE. Still looks like a cloudy outlook although UKMO and ECM have more chance of the sun coming through as the cloud burns back.

[BLAST FROM THE PAST]

lol whats scirocco easterlies got to do with model discussion and the UK for that matter, thought i entered the wrong thread here, anyways some model discussion from me,

Haven't read the whole thread then? Temps to max out at 16/17c then drop for the south by weekend to 12c as the easterlies set in.

BFTP

pardon my spelling, but to my knowlege we have no word to discribe a warm easterly, hence 'scirocco type' of wind....

Read your later entry afterwards.....I know where you are coming from.

BFTP

[ANYWEATHER]

Not sure any model is accurate as regards cloud cover and precip from an Easterly direction at this time of year. Yes, given the synoptics it could be warm it could be cold, looks as though the gfs wants to bring on a late cold spell for the southern half of the uk??

[Thundery wintry showers]

ECM has the high further south at T+144 as per UKMO but then shows the high migrating north thereafter- the implication is a reasonably sunny warm weekend for almost everywhere but then turning cool and dull in eastern areas into next week. I'm still reserving judgement on this potential easterly as this easterly does seem to be being pushed back with successive runs.

[mushymanrob]

oh dear, this mornings gfs is much worse for cloud cover then the last run i viewed (yesterdays 06z). much breezier in the southern half of the uk pretty much throughout. the only saving grace is that it should be dry, assuming drizzle doesnt occur.

add my name to the list of north sea grey skies 'hater'.

[phil nw.]

oh dear, this mornings gfs is much worse for cloud cover then the last run i viewed (yesterdays 06z). much breezier in the southern half of the uk pretty much throughout. the only saving grace is that it should be dry, assuming drizzle doesnt occur.

add my name to the list of north sea grey skies 'hater'.

Looks fine up to the end of the week though,after todays front dies away,with the High placed pretty much over us.

Disagreement between the models starts after day 4 with GFS indeed showing a brisk Easterly for much of England and Wales later which would bring in the cold and cloudy North Sea cloud for many Central and Eastern areas.

UKMO and ECM have the High a little further South with much lighter winds for most and any cloud should have a better chance of burning back to the coast during the day.

[johnholmes]

oh dear, this mornings gfs is much worse for cloud cover then the last run i viewed (yesterdays 06z). much breezier in the southern half of the uk pretty much throughout. the only saving grace is that it should be dry, assuming drizzle doesnt occur.

add my name to the list of north sea grey skies 'hater'.

welcome aboard mushy

And yes its not a very nice outlook on the 00z after the end of this week-mostly 'green' for temperatures for much of the UK, thanks to the surface high with its upper air block to the NW.

We can only hope its wrong!

[Nick F]

00z GFS shows almost uninterrupted easterlies from Monday to t+384 ... I hope we are not in for a protracted spell of dull, damp and raw easterlies! Looks like west will be best once the easterly gets going and the low stratus starts to roll in from the east, usually the sun is strong enough now to burn it back across western areas.

Some notable mid-latitude blocking on the 00z 8-10 day mean HGT comparisons and -ve anomalies over the pole:

http://www.meteo.psu.edu/~gadomski/ECMWF_0z/hgtcomp.html

[MP-R]

A very depressing run right up until around the 22nd when I see a potential change to something more interesting:

http://www.wetterzentrale.de/pics/Rtavn3841.png

Very much at the end of FI but the first interesting chart in the whole lot at present. If that low can move northwards then westerly winds will return and we may finally see an end to the easterly. Alternatively, I'm still considering the easterly either being watered down considerably or not even happening at all.

[johnholmes]

Some notable mid-latitude blocking on the 00z 8-10 day mean HGT comparisons and -ve anomalies over the pole:

http://www.meteo.psu...0z/hgtcomp.html

yes there is little in that sort of time frame from any model that suggests much activity across the Atlantic in the UK latitude. Not promising to me for this time of the year but then others seem to like raw, coldish flows off the N Sea?

[Frosty.]

Not much change from the models compared to yesterday, the gfs still toying with the idea of a cold unsettled spell later in FI but the ecm is having none of it. In general, there is agreement for a settled spell lasting at least a week and possibly much longer and that northern britain with particular emphasis on scotland, ultimately being the sunniest and warmest part of the uk as hp settles across the north with southern britain picking up a cooler flow off the cold north sea with more cloud as well.

[Thundery wintry showers]

The models seem to be coming into agreement now- a warm, sunny weekend looks likely for almost all parts of the country, but then the easterly is set to pick up next week. The easterly doesn't look set to be as pronounced as was suggested by GFS in earlier runs, so I think much of Scotland and western England/Wales/Ireland should stay "in the clear", but it looks like low cloud will indeed become prominent over eastern and possibly central England.

With just a modest easterly flow it probably won't be wall-to-wall cloud, with some breaks probably coming through at times mainly during afternoons, but an overall cool, cloudy week is looking likely in the east- East Anglia in particular looks likely to be largely sunless for a while. As some other posts have suggested, strong northern blocking could lock this pattern in for some time.

[Big Innes Madori]

Not much change from the models compared to yesterday, the gfs still toying with the idea of a cold unsettled spell later in FI but the ecm is having none of it. In general, there is agreement for a settled spell lasting at least a week and possibly much longer and that northern britain with particular emphasis on scotland, ultimately being the sunniest and warmest part of the uk as hp settles across the north with southern britain picking up a cooler flow off the cold north sea with more cloud as well.

Ah Frosty mate,

You are saying all the right things (IMBY)

However, in these parts I will always need to keep an eye on any Easterly flow, as we can be badly affected by the dreaded North Sea Haar

I have seen many a potential beautiful summers day ruined by that dammed stuff , while a few miles further inland to the west and it's Summer Time while the living is easy

Nice day here at the mo

Big Innes

[mushymanrob]

thankfully the 06z doesnt confirm the brisk easterlies of the 00z, although kent could be raw at times. mid fi has a hint of spring 1975 about it but hopefully any northerlies/northeasterlies wont last, i dread a repeat of spring 75.

[Nick F]

thankfully the 06z doesnt confirm the brisk easterlies of the 00z, although kent could be raw at times. mid fi has a hint of spring 1975 about it but hopefully any northerlies/northeasterlies wont last, i dread a repeat of spring 75.

I'd be happy of a repeat if it meant we would get a long hot summer like 1975!

Seems to be a hint of deja-vu from GFS this morning with the synoptics we had during the past winter ... albeit the airmasses have warmed up somewhat now.

[mushymanrob]

I'd be happy of a repeat if it meant we would get a long hot summer like 1975!

yeah but knowing my luck the summer would be like 1985!

[conor123]

The 12z is a cracker from start to finish with high pressure over or near the UK right to the end of the run with a heatwave far out in FI.

As for the next few days, looks a bit questionable how much sunshine were see, if it can be this sunny without todays chilly howling wind it would be nice.

[The PIT]

Mmm depends on how much cloud is sucked in. Western areas should be fine but I feel the GFS is over cooking the eastern temps a little.

[Derp Patrol]

Yes a great end to the GFS 12z run which would definately bring the first proper warmth of the year in a southerly/south easterly wind flow with uppers around 8C. 22-24C would be realistic from that set up in the south east if there is sun, but at the moment it's too far out. Still much improved charts though!