Model output discussion - 20th Feb onwards

[knocker]

 

[knocker]

A brief look at the weather for the next week courtesy of GFs and METO fax.

The weather continues to be dominated by the upper low to the south west so will remain unsettled for the period. The temps generally will be around average although perhaps slightly above in the south as the upper flow remains in the SW but surface detail swinging from there to easterly as systems jockey for position.

From Sunday through to the middle of the week some wet and windy weather, particularly in the SW,  as fronts push NE. The rest of the week probably dominated by instability and heavy showers as the the streamlines become more consistent from the SW but I imagine this open to some change in the next couple of days.

Edited April 9, 2016 by knocker

[knocker]

This will never do. The cognescenti might start twitching

 

 

Edited April 9, 2016 by knocker

[knocker]

Although varying in detail the general picture from the ecm is basically the same as the GFS. Unsettled, periods of more pronged rain and quite windy otherwise heavy showers. perhaps thundery and sunny interludes. (should cover it). Temps varying a great deal but on average cooler in the north and perhaps a little above further south.

 

Edited April 9, 2016 by knocker

[049balt]

Someone expects some dry weather, in a weeks time.

Edited April 9, 2016 by 049balt

[Milhouse]

Following a rather unsettled week it looks like odds in favour of an easterly developing, whether its a warm or cold one is still very much up in the air.

 

The control run sends a lovely plume northwards in FI

 

 

Edited April 9, 2016 by Milhouse

[049balt]

Once again signs of much dryer weather a week or so out.

[Summer Sun]

8 minutes ago, 049balt said:

Once again signs of much dryer weather a week or so out.

High pressure starting to build in the latter stages of GFS hence the drier signal on this run

[049balt]

1 minute ago, Summer Sun said:

High pressure starting to build in the latter stages of GFS hence the drier signal on this run

It seems too good to be true, lets hope other models come on board.

[Milhouse]

Becoming fine and settled at day 10 according to the ECM 12z mean although with an easterly wind blowing it would be rather chilly on eastern coastal areas but becoming warm in the sheltered SW.

 

[stodge]

Evening all

The coming week seems fairly well set with the onus on unsettled conditions with plenty of rain and showers especially around midweek as the trough re-invigorates briefly across the British isles thanks to a feed of cold air from Scandinavia.

Looking a bit further on - GFS from the 12Z OP output at T+216:

ECM at the same time:

Very similar and suggesting HLB with the jet kept well to the south.

GEM perhaps the best for those looking for some drier and settled conditions:

GEM has the core of higher pressure a little closer and the LP further west in the mid Atlantic keeping a more S'ly component in the windflow. 

[knocker]

The likely weather until next weekend courtesy the GFS and METO.

The upper low continues to dictate proceedings which comes as no surprise. So continuing unsettled with rain strong winds particularly in in the south west for today, and later in the week heavy showers as low pressure remains in the proximity of the UK and slowly fills. The worst of the weather in the south and west. Temps quite cool at first but progressing upwards during the week, more particularly in the south.

The first part of the week quite wet as fronts track NE into the Midlands and stall. The best of the weather will be in Scotland and the north of England

Edited April 10, 2016 by knocker

[Singularity]

Some encouragement from the 00z ECM if you're looking for a drier theme starting around a week from now; it has increased the level of influence from high pressure E and NE of the UK, low pressure held back to the SW with a warm, dry SE flow across our land.

Before that, the notion of LP moving across the UK on Friday and tipping the balance of power in favour of a cool airmass for much or all of the UK has been dropped again after appearing last night. So it is that at least the southern half of the UK remains in the warmer air with temps generally hitting the mid to high teens each day, despite showery rain.

[Gibby]

HERE IS MY LATEST ANALYSIS USING DATA SUPPLIED BY THE NWP OUTPUT COVERING 5 OF THE WORLDS MOST POWERFUL WEATHER COMPUTERS ISSUED AT 09:00 ON SUNDAY APR 10TH 2016

THE CURRENT GENERAL SITUATION A deepening depression lies down to the SW of the British isles today with a developing East or SE flow across the UK, very strong in the SW. Troughs of Low pressure will swing up across the South and West of the UK later today and more especially tomorrow while the East flow steadily slackens again.

http://www.wetterzentrale.de/pics/Rtavn001.gif

CURRENT SNOW FORECAST AND FREEZING LEVEL OVER THE UK The cold uppers across the UK with freezing levels under 2000ft will lift today and tomorrow with levels exceeding 5000ft for all and perhaps as high as 6500ft across Eastern Britain removing the risk of snowfall above all summits south of Scotland in the next few days.

http://www.snow-forecast.com/maps/dynamic/uk

http://www.natice.noaa.gov/pub/ims/ims_gif/DATA/cursnow.gif

MODELS-2 WEEK HEADLINE Rather unsettled with some rain or showers at times. Probably turning drier with time especially across the North and East.

THE GFS JET STREAM FORECAST  All indications are that the Jet Stream will remain well South of the UK for some considerable time from this morning's predictions from GFS influenced by persistent Low pressure down to the SW of the UK for much of the period. It may change it's alignment somewhat in Week 2 but maintain a position far from ideal for any major Spring warm outbreak for the UK.

http://www.netweather.tv/index.cgi?action=jetstream

GFS OPERATIONAL The GFS Operational Run today endorses the Jet Stream forecast above with Low pressure down to the SW of the UK dominant throughout the coming week as spores from it evolve NE across the UK. In week 2 more Low pressure over or near the UK maintains showers and longer spells of rain and strong winds too a risk but with as always some drier and brighter exceptions at times.

GFS CONTROL RUN The GFS Control Run is pretty much the same although day to day differences are apparent and in Week 2 a gradual erosion away from the South of the lowest pressure swings winds into a strong West or SW point with some drier and warmer spells developing across the South and East with time and pushing the worst of the wind and rain away to the more traditional pattern of the North and West.

http://www.wetterzentrale.de/pics/Rtavn1441.gif

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

http://www.meteociel.fr/modeles/gefs_cartes.php?code=0&ech=144&mode=0&carte=0

http://www.meteociel.fr/modeles/gefs_cartes.php?code=0&ech=384&mode=0&carte=0

GFS ENSEMBLE DAY 14 DATA  The GFS Clusters today show a very mixed bag of options possible in 14 days ranging from a continuation of unsettled UK based Low pressure pattern whereas there is some more encouraging evidence of higher pressure close by from about 25% of members.

http://www.weatheronline.co.uk/cgi-bin/expertcharts?LANG=en&MENU=0000000000&CONT=euro&MODELL=gefs&MODELLTYP=2&BASE=-&VAR=cpre&HH=372&ZOOM=0&ARCHIV=0&RES=0&WMO=&PERIOD=

UKMO The UKMO model this morning shows a more encouraging picture than of late as Low pressure to the SW weakens through the week and a ridge of High pressure gradually extends some influence down across the UK from the NW so that many places could end the week rather drier though with rather chilly air at times especially over the North and East where frosts at night look possible along with some showers near the East coast.

http://www.wetterzentrale.de/pics/Rukm1441.gif

THE FAX CHARTS The Fax Charts illustrate a very complex week of weather to come with the day to day detail very hard to pin down from place to place but in general it would appear that some rain or showers can be expected for many especially across the South where it could feel rather warmer than of late all due to Low pressure and troughs feeding up from the SW at times.

http://www.weathercharts.org/ukmomslp.htm#t120

GEM GEM today shows another version of the unsettled theme with it showing Low pressure near or over the UK in the coming week with rain at times along with some cool air too at times especially over the North. Then a brief drier spell looks likely across the South and East as pressure builds there before further Low pressure off the Atlantic moves SE into the UK later with more rain and showers for most.

http://www.wetterzentrale.de/pics/Rgem2401.gif

NAVGEM NAVGEM today shows a very slack Low pressure area across the UK for much of the next week fuelling a lot of heavy and slow moving thundery showers for many especially over inland areas through the afternoons with some cool and clear nights empowering the risk of some ground frosts by night especially over the North. Being April though some warm sunshine will also be present for all, warmest in the Sooth in the first half of the week.

http://www.wetterzentrale.de/pics/Rnvg1681.gif

ECM ECM on the other hand follows it's partner UKMO in showing rather better conditions developing later in the week as Low pressure to the SW weakens and a ridge pushes down across the UK from the NW culminating in a High pressure area near the North Sea by next weekend which then gently evolves NE to allow a SE flow to develop across the UK with rain bearing fronts over the Atlantic appearing to hold off towards the far SW by the end of the 10 day period.

http://www.wetterzentrale.de/pics/Recm2401.gif

ECM 10 DAY MEAN (12z) The 240hr mean Chart from this morning is a very complex chart giving few if any clues as to what we can expect in 10 days time. On the face of it the chart is much improved from recent days but this is a day when the chart offers little depiction of what we might expect as there is a fairly even split of members opting for showery Low pressure persisting and those that show High pressure more influential towards the NE of the UK.

http://www.wetterzentrale.de/pics/Reem2401.gif

NOTABLE TRENDS & CHANGES FROM PREVIOUS RUNS Although there is still a fair amount of support for Low pressure based conditions to continue across the UK there are encouraging signs from the most reputable models of UKMO and ECM that the other models may be too progressive in their prediction and that as a result rather drier and more benign conditions could more likely develop towards next weekend and beyond.

31 DAY HISTORICAL VERIFICATION STATS FOR GFS, UKMO & ECM The verification Statistics of GFS, UKMO and ECM show at 24 hours ECM ahead at 99.6 pts with UKMO at 99.5 pts and GFS at 99.4 pts.  At 3 days ECM is leading with 97.5 pts to UKMO's 97.0 pts while GFS lags behind at 95.9 pts. At 5 days ECM leads with 89.6 pts to UKMO at 88.0 pts and GFS at 84.6 pts. Then at 8 Days ECM has the leading spot from GFS with 64.8 pts to 58.9 pts. Finally at Day 10 ECM has the lead from GFS with a score of 44.1 pts to 39.9 pts.

http://www.emc.ncep.noaa.gov/gmb/STATS_vsdb/allmodel/daily/cor/cor_day1_PMSL_MSL_G2NHX.png

http://www.emc.ncep.noaa.gov/gmb/STATS_vsdb/allmodel/daily/cor/cor_day3_PMSL_MSL_G2NHX.png

http://www.emc.ncep.noaa.gov/gmb/STATS_vsdb/allmodel/daily/cor/cor_day5_PMSL_MSL_G2NHX.png

http://www.emc.ncep.noaa.gov/gmb/STATS_vsdb/allmodel/daily/cor/cor_day8_PMSL_MSL_G2NHX.png

http://www.emc.ncep.noaa.gov/gmb/STATS_vsdb/allmodel/daily/cor/cor_day10_PMSL_MSL_G2NHX.png

MY THOUGHTS There are a few more encouraging signs from some of the most respected models this morning as this weeks anticipated Low pressure might not give us the persistent rain and showers that previous model runs indicated. However, the pattern is far from straightforward as Low pressure to the SW in a cut off condition that it is can be notoriously fickle beasts for models to deal with as the general filling and movement of the Low can be instrumental in where we move thereafter and there are plenty of very feasible options on the table this morning ranging from unsettled, wet, windy and cool weather to dry and bright conditions with a benign pressure pattern across the UK hinted at by the Euros. I think a few more days are needed before the end of the week pattern can become more agreed and established between the models and while that time is elapsing it looks like some rain or showers will continue across the UK, especially in the South until the middle of the week at least and in that time it will feel rather warmer at times than of late. So rather than dwell on which models have the best handle on the longer term synoptics I will wait a day or two more before casting any judgement on what lies ahead of us beyond this week. The one thing I can say is that there is nothing nasty likely for anyone and it all shapes up to be a far from untypical pattern for this time in Spring.   

Next Update Monday April 11th 2016 from 09:00

[johnholmes]

Some indications on the 3 anomaly charts I use to suggest that the long wave pattern is about to change, see below. EC is the most definite showing a ridge developing east of the UK, but the trend is there on all 3, after quite a spell showing the pattern we have at the moment, to change over the 5-10 day period.

http://www.cpc.noaa.gov/products/predictions/814day/500mb.php

http://mp1.met.psu.edu/~fxg1/ECMWF_0z/hgtcomp.html

copare the NOAA 6-10 above with the one below, about 8 days ago. This type had been solidly shown for a number of days prior to the one shown and for a couple of days after before changes started to show.

 

 

sunday 10 april chart for post.doc

Edited April 10, 2016 by johnholmes
file added

[knocker]

Yes I was just about to say something similar as this trend appeared last evening

The GEFs and ecm 6-10 this morning

 

Edited April 10, 2016 by knocker

[carinthian]

1 hour ago, johnholmes said:

Some indications on the 3 anomaly charts I use to suggest that the long wave pattern is about to change, see below. EC is the most definite showing a ridge developing east of the UK, but the trend is there on all 3, after quite a spell showing the pattern we have at the moment, to change over the 5-10 day period.

http://www.cpc.noaa.gov/products/predictions/814day/500mb.php

http://mp1.met.psu.edu/~fxg1/ECMWF_0z/hgtcomp.html

 

Hope it comes off John.Want to make a trip back to Blighty to watch a bit of cricket. Far too cold for my liking over there at the moment.

C

[knocker]

The GEFs 06Z 10-15 is quite similar to the EPS 00z 10-15

 

 

 

 

Edited April 10, 2016 by knocker

[049balt]

16 minutes ago, knocker said:

The GEFs 06Z 10-16 is quite similar to the EPS 00z 10-15

 

 

 

 

The Meto now coming on board with some dry and pleasant weather in the forecast.

Edited April 10, 2016 by 049balt

[knocker]

13 minutes ago, 049balt said:

The Meto now coming on board wit some dry and pleasant weather in the forecast.

Yes I've just noticed. Just depends now on the orientation of the HP.The EPS 850mb chart for the 23rd (can't post) has it more to the SW thus keeping to a NE flow but it's bit early to consider these details. Let's get the HP in place first.

Edited April 10, 2016 by knocker

[049balt]

Where is everyone?

[Summer Sun]

Not especially warm but settling down possibly towards next weekend though the south remains at risk of some showers at times

 

Edited April 10, 2016 by Summer Sun

[knocker]

I'm here but we have quite a violent thunderstorm in progress at the moment.!

The GEFS this evening is continuing the theme of ridging through the North Sea at the latter end of the 5-10 with the trough retrogressing. And then in 10-15 period the HP in the eastern Atlantic pushing north into Iceland. Can't be bad.

[damianslaw]

Trend from all models is for something more settled as we move through the week, with low pressure to our SW becoming less of a feature as the week wears on as high pressure nudges in from the NW - its not a warm synoptic though, airstream from between west and north. Jury out on whether we see these heights build into the country pulling in a more warmer SE continental feed, or sitting to our NW maintaining a colder feed from the north with low heights building back in from the SW - back to square one.

When we see the influence of heights to the north at this time of year they can be a very stubborn feature,cold  northerly and easterly airstreams tend to have a far easier time of it at this time of year than at any other - so don't put those woolies away just yet!

[stodge]

Evening all

Certainly a couple of steps forward for those wanting drier and warmer conditions on the evening's output. The midweek re-invigoration of the trough over the UK has been more or less dropped and while the cut off LP to the SW remains the dominant feature for the early part of the week, the signs are now growing for a more settled end to the week.

GFS 12Z OP for next Sunday afternoon:

ECM at the same time:

GEM at the same time:

Quite a difference there so this may not be the done deal some on here seem to think. Basically, GEM brings the trough back over the UK and there is no build of HP to the north.

Let's see what the morning brings...