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2 hours ago, knocker said:

Monday > Weds with the 600 ecm

PPVG89.thumb.gif.05290c6767b7aa94017ec3d8a610229a.gifecmwf-deterministic-uk-gust_kt-7394800.thumb.png.e4f547c44ee321a3e56abcddc9803914.pngecmwf-deterministic-uk-t2m_c_max6-7405600.thumb.png.3f60669158eccbf20bc8b9b14a1c88f9.pngPPVJ89.thumb.gif.cf78f09f022a38971ea9485087bd859f.gifecmwf-deterministic-uk-gust_kt-7481200.thumb.png.fde53634ce8e23dfdd6b7dd88e2e75a7.pngecmwf-deterministic-uk-t2m_c_max6-7492000.thumb.png.8c6dc3a6fff7a090aaf78a89d0fc48cd.pngPPVL89.thumb.gif.08b8798eefafb99808745938ff6a5ec9.gifecmwf-deterministic-uk-gust_kt-7567600.thumb.png.6c3897537c9019af6933707ff644fc41.pngecmwf-deterministic-uk-t2m_c_max6-7578400.thumb.png.1cceda96fac6007678acd422fe08ef8f.png

Current sat image

met_images_aspx.thumb.png.8bb839e4f68ed8ebcd81ba1bf95313df.png

I live in hope that it is correct re cloud as the wind is not pleasant. My time in the east makes me very suspicious of strong easterly and no low cloud, I hope I am wrong.

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Differences opening up with model forecasts of MJO progression. ECM staying in the neutral zone whilst GEFS and JMA showing progression from Phase 6 into Phase 7. ECM  GEFS  JMA  Phase 7 is

The intense amplification over North America with the Arctic plunge down the eastern half initiates downstream ridging of the subtropical high which simultaneously pumps up the jet.

Quite a good illustration showing absolutely no correlation between the 850mb and surface temps in the relatively 'warm' airmass in an Autumn anticyclone

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13 minutes ago, johnholmes said:

I live in hope that it is correct re cloud as the wind is not pleasant. My time in the east makes me very suspicious of strong easterly and no low cloud, I hope I am wrong.

It will be interesting to see how it pans out. The old Boulmer and Hemsby soundings might have helped ?

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The North Atlantic 500mb and surface analysis for midnight and the current sat image

gfs-deterministic-natl_wide-z500_anom-7340800.thumb.png.8b029c509960c8a82918f12e5f518ac3.pngPPVA89.thumb.gif.ea741a4e41613f820d8b0fb923bc2e9f.gifmet_images_aspx.thumb.png.6eba88ae6b109ffba46818d8dd90a744.png

Another bright and sunny day and quite warm if you are not effected by the stiff easterly wind where the usual caveats apply.To save repetition takes this as read for the next three or four days.The only exception being the far south west where it will be cloudy with possibly the odd shower

PPVE89.thumb.gif.c5c1f4affeae2c7cff63c7b8f17b07c9.gifgfs-deterministic-uk-t2m_c_max6-7405600.thumb.png.73955059b09d3a796a53449653c1b872.png

Clear tonight apart from the south west

PPVG89.thumb.gif.0a7aed7aaa9bdd28b09f36d1778a9bbb.gif

A similar day tomorrow with the gusty easterly still the only drawback

PPVI89.thumb.gif.879c67448fd23c2b3ea0a45c52166500.gifgfs-deterministic-uk-t2m_c_max6-7492000.thumb.png.bbea3320f296e02c0064ad4fa01d3c04.png

Over Tuesday night and through Weds little change but the south west may lose the cloud and the wind will ease and getting warmer

PPVK89.thumb.gif.b3295183ba0c4d0e574039203c4161b2.gifgfs-deterministic-uk-t2m_c_max6-7578400.thumb.png.c70e4cb66b276699f325c9296ac0b9cb.png

By Thursday changes in the NH profile, as mentioned in previous posts, are underway and the high pressure to the NE is migrating west leaving the UK in a slack gradient and another warm and sunny day

gfs-deterministic-nhemi-z500_anom-7643200.thumb.png.da35096efc355a927e1c58b66f0fe90a.pngPPVM89.thumb.gif.419df88bef4fb892af8b5731265fc1f7.gifgfs-deterministic-uk-t2m_c_max6-7664800.thumb.png.d140f9a5ec7fb585c5cba9b7bf30485f.png

The transition continues on Friday with frontal systems creeping east across the Atlantic but the UK remains in a very slack gradient and a another warm day is on the cards with perhaps more chance of a few showers popping up

gfs-deterministic-nhemi-z500_anom-7729600.thumb.png.5fec3581d889098c2d50d13196748993.pngPPVO89.thumb.gif.8e37996f4766de96ec1e4ba06d8a1293.gifgfs-deterministic-uk-t2m_c_max6-7751200.thumb.png.e84e6683991de20186fc9e4f19d72f8f.png

Edited by knocker
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According to the gfs another slack gradient day on Saturday with perhaps more chance of showers in the south

132.thumb.png.c40872f34e2fe7df97d41bcd219536db.pnggfs-deterministic-uk-t2m_c_max6-7837600.thumb.png.375998ff128cdce161afe93a43582567.png

But as can be seen the Atlantic is now open for business south of the high cell and a low pressure area moves east across the UK Sun/Mon and thus more generally unsettled

gfs-deterministic-nhemi-z500_anom-7902400.thumb.png.1447d0eddf0084922854996ccc659926.pnggfs-deterministic-nhemi-z300_speed-7902400.thumb.png.32d37018c4a2dc0f2f4f9e06be405161.png

156.thumb.png.992a168066479d95e318723335c007c3.png180.thumb.png.fa1b471a5433c9313cf97d3504763a86.png

 

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I have absolutely no idea how much credence one can give near time model cloud forecasts but out of interest the spot check at 1500 for the total amount today > Thursday from the ecm. Today and tomorrow it is mainly medium cloud and Wed/Thursday Ci

ecmwf-deterministic-uk-total_cloud-7394800.thumb.png.0f0f49a32610e1c567c8af14763aff88.pngecmwf-deterministic-uk-total_cloud-7481200.thumb.png.37d2b9769429121e0d078c76eb3cfb66.pngecmwf-deterministic-uk-total_cloud-7567600.thumb.png.92113d46b0f871a288773be2f6e7c865.pngecmwf-deterministic-uk-total_cloud-7654000.thumb.png.d4f58550f4fbda06b4ea7eb7cdeb85c1.png

 

 

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And predictable the ecm wants nowt to do with the gfs idea of tracking the trough east over the UK next weekend and has a resurgence of the subtropical high and thus a ridge stretching NE over Sun/Mon

ecmwf-deterministic-nhemi-z500_anom-7816000.thumb.png.a3983ac7a7c3ceaa87a32c6419e6ef70.pngecmwf-deterministic-nhemi-z500_anom-7902400.thumb.png.fbeaed8be62dc0eb67c4558dae1761a7.png

 

Edited by knocker
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As has been mentioned by others it's interesting that no low cloud along the east coast is included in the forecasts. Just an observation as this is way above my pay grade but the SST's of  North Sea are over a degree C above average and looking at the Schleswig sounding the air is very dry so one assumption could be that there  is not sufficient mixing in the boundary layer for St to form 

sst.thumb.JPG.54bdbcc1e053afb213a0d982be0f5c1b.JPGwind.thumb.JPG.a8eb4148ba1e2d32d5b84e1c79ba451e.JPG2020042000.10035.skewt_parc.thumb.gif.9b7ae8e2624df1943163967b95e19caf.gif

This morning's rainfall from the EPS

ecmwf-ensemble-avg-uk-total_precip_mm-8636800.thumb.png.a7bbcd9216686c904fb9343acbacd040.png

Edited by knocker
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There were major differences between the gfs and ecm this morning regarding next weekend.The gfs has changed drastically with the 0600 but still differing so a quick glance at the clusters At t132 the det run is close to the first cluster but as van seen that isn't a slam dunk

ecmwf-deterministic-natl_wide-z500_anom-7816000.thumb.png.68a3aed01a7abf9f0c6ca0b7021e2504.pngec-ens_nat_z500scenarios_2020042000_132.thumb.png.412de86278d0ddd4e7e51d98273afcb6.png

The same can be said at t144 but as can be seen there is virtually an even spread on the different interpretations of the orientation of the upper trough and ridge. Place your bets

ecmwf-deterministic-natl_wide-z500_anom-7859200.thumb.png.9eac508608833ec6975d113e5e4278a3.pngec-ens_nat_z500scenarios_2020042000_144.thumb.png.6a27b772ea388ea1990532d7260de29d.png

 

Edited by knocker
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Tricky business next weekend. This evening the gfs has a shallow trough breaking away from the main trough in the Atlantic and ducking south east a the subtropical high amplifies, which promotes a showery low over the UK on Sunday

gfs-deterministic-natl_wide-z500_anom-7859200.thumb.png.3ecaa8e30380f3fe46742333f28e5460.pnggfs-deterministic-natl_wide-z500_anom-7902400.thumb.png.669678554095fb84a8aef1a70ca83510.png144.thumb.png.20b9318e5490f48e0cda3c3443237f22.png

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The ecm is not having any of this. A possible movement to track a breakaway trough east at t120

ecmwf-deterministic-natl_wide-z500_anom-7816000.thumb.png.aea6ed84b9830c2f3c2d7828b509aa7b.png120.thumb.png.55bb802e6fb148fe3f1cb1b6c736ca99.png

But further amplification of the subtropical high puts paid to that and by Sunday the UK nestles in the eastern flank of the new high cell

ecmwf-deterministic-natl_wide-z500_anom-7902400.thumb.png.9f91edc337b8746c8f4fa32563128c6d.pngecmwf-deterministic-natl_wide-z300_speed-7902400.thumb.png.dc5d7417402a3f43ccfcff1c56ed93fa.pngindex.thumb.png.bfe0dcbed391d7e8422ea86523bb773d.png

 

 

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Apart from being the lower half of the H/L UK squeeze fronts associated with the low pressure to the south are bringing cloud and rain to Devon and Cornwall at the moment

PPVA89.thumb.gif.a19f4fd452d123a164c4ab461ef4946c.gifmet_images_aspx.thumb.png.50bab34a72abfd18094a3620f4dd3938.png

This can be well illustrated by looking at the midnight soundings for Camborne and Nottingham. The former, although reasonable dry in the lower regions, indicates multiple cloud layers above whilst the latter with a touch of surface cooling, is very dry above. Also worth noting the light NE surface wind veering to 085/39ks by 961mb

2020042100.03808.skewt_parc.thumb.gif.f7b2e6c0e0e06c3d03556a1554d75a9c.gif2020042100.03354.skewt_parc.thumb.gif.f81799a3ebe9b4de41302b5e7c3a51ee.gif

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Moving on to the elusive analysis for the weekend

This is the 500mb and surface position on Friday indicating a very slack gradient over the UK  More cloud than earlier in the week but still warm with showers, heavy in the south

gfs-deterministic-natl_wide-z500_anom-7729600.thumb.png.43e7994688fc22e1e32a074506b76ba8.pngPPVM89.thumb.gif.19aa828539ac1d098efb76c4b8d70ac9.gifgfs-deterministic-uk-t2m_c_max6-7751200.thumb.png.f2701314005c325c0cf9ae9ce049f48f.png

A very similar day on  Saturday

PPVO89.thumb.gif.4cfb11a713bf068057b125d4f2a3de56.gifgfs-deterministic-uk-t2m_c_max6-7837600.thumb.png.95c21f2362e0892685e71a58378740b5.png

And again little change on Sunday although the gfs has slipped the weak trough south east from Iceland

gfs-deterministic-natl_wide-z500_anom-7902400.thumb.png.986cfef9d306145038b478716e412966.png132.thumb.png.275990538379ad3a7c4e42fcb1dd40b9.pnggfs-deterministic-uk-t2m_c_max6-7924000.thumb.png.3deb85dae3e7192ed0cfe444e87b416e.png

 

Edited by knocker
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The ecm makes a bit more of the trough to the north on Sunday as it phases with the main trough to the north east. This brings some rain to northern Scotland and does impact on the temps.

ecmwf-deterministic-natl_wide-z500_anom-7924000.thumb.png.7787266f554c1d649dc4b66e2474f211.png138.thumb.png.19bc3bdf279209a20ed602d78a8ead19.pngecmwf-deterministic-uk-t2m_c_max6-7924000.thumb.png.57be4e4d67451cd1690cc9415fa0f5ba.png

This then develops into a separate low over southern Scandinavia but still leaving western Europe, including the UK, in a very slack low pressure area

ecmwf-deterministic-natl_wide-z500_anom-8075200.thumb.png.6e48feb93c6902ce906a6880c3dad2c2.png180.thumb.png.67acab4d02a2a9680b29e7c9a713e8cc.png

Edited by knocker
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By the time we get to the ext period this morning the tpv has realigned and lost the trough to the NE to be replaced by height rises over Scandinavia, At the same time the main trough ii negatively tilted south east from Greenland. The precise intensity and alignment of these features is critical to the detail of the surface analysis but suffice it to say nothing .nasty would appear to be lurking in the woodshed

ecmwf-ensemble-avg-nhemi-z500_anom_5day-8636800.thumb.png.9438e67369fcb2438cc0fd4bf2253c6e.pnggfs-ensemble-all-avg-nhemi-z500_anom_5day-8636800.thumb.png.c37b39615b8f2cb3fac816d5a0a0111a.png814day_03.thumb.gif.0c2dba4a9aadb3344d76624b77865f28.gif

ecmwf-ensemble-avg-eur-t2m_c_anom_5day-8636800.thumb.png.e8073fab984faed29ad04fbf7f6623f9.pnggfs-ensemble-all-avg-eur-t2m_c_anom_5day-8636800.thumb.png.b8720a933490d0f6212c86cbc47e43cc.png

 

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A glance at today's EC weeklies update for the last two weeks of May

15 - 22

A ridge NW North America adjacent to a benign tpv aligned Franz Joseph to N. Canada with associated trough to the NW Atlantic. A weak westerly upper flow to some height rises and positive anomalies in the east with a ridge into south east Greenland and apparently a slack gradient south of the UK over western Europe/ Portends dry and not unpleasant

ecmwf-weeklies-avg-natl_wide-z500_anom_7day-0105600.thumb.png.cbdfa3bf5abccb985997ccdd624a9919.pngecmwf-weeklies-avg-eur-t2m_c_anom_7day-0105600.thumb.png.8d9e75ee461d61a8d91ed0d437a7acd8.pngecmwf-weeklies-avg-eur-precip_168hr_inch-0105600.thumb.png.2f4397138566cc7117cb6b754683051c.png

23 - 30

The Atlantic trough a tad more influential and losing the positive anomalies and ridge in the east but really little overall change for the UK except perhaps a tad more unsettled which will favour the north rather than the south

ecmwf-weeklies-avg-natl_wide-z500_anom_7day-0796800.thumb.png.de1ca23f9d5c2741d35c9defd4f25a09.pngecmwf-weeklies-avg-eur-t2m_c_anom_7day-0796800.thumb.png.81c82fb157d3a826a40164c804e122ec.pngecmwf-weeklies-avg-eur-precip_168hr_inch-0796800.thumb.png.88a5f505f5d292d0995eb20ce828fb5c.png

Edited by knocker
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According to this evening's ecm next weekend looks like finding the UK in a light gradient with perhaps a few showers but more persistent rain arriving in the NW Sunday afternoon

ecmwf-deterministic-natl_wide-vort500_z500-7859200.thumb.png.9c042b5cc2c45a55715070681134335a.pngsat.thumb.png.9d9c7befca24431edb6abfcde6181da3.pngsun.thumb.png.0666579f7f6d550f662c806cf1cba528.pngecmwf-deterministic-uk-t2m_c_max6-7837600.thumb.png.5ddb9eac7801bdcf0b5a2b02609dd1b3.pngecmwf-deterministic-uk-t2m_c_max6-7924000.thumb.png.d16c315780c08c3c1571a020f43cd2a9.pngecmwf-deterministic-uk-precip_6hr_inch-7945600.thumb.png.fd529b6544d2acfc528a096eafbd7016.png

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I think most are aware of the current situation so keeping the waffle to a minimum

Today a dry dry and sunny day with the usual caveat

PPVE89.thumb.gif.c01df455055016c0e11e73fae405ceae.gifgfs-deterministic-uk-t2m_c_max6-7578400.thumb.png.b282db730691065f07a97cd7bfbb277c.png

After a clear night with perhaps some bits and bobs of cloud around in the north another fine day tomorrow but the fresh wind will ease

PPVI89.thumb.gif.389f39b7e096cfb2eb2ef1e49fb56114.gifgfs-deterministic-uk-t2m_c_max6-7664800.thumb.png.2b5ae61194845ee4c2084602b33029e2.png

Another fine day on Friday but note the very slack pressure gradient over western Europe

gfs-deterministic-eur-z500_anom-7729600.thumb.png.f3969b483fd7d843bfdd8529bebb05a1.pngPPVK89.thumb.gif.af6aa7b7d6c6eb0d8079944b1f278c32.gifgfs-deterministic-uk-t2m_c_max6-7751200.thumb.png.f836fb61325a08c0ed1a86bac7a0595a.png

By Saturday the low pressure area to the SSW is developing a tad so a few showers in south western areas and a shallow trough is tracking south east south of Iceland

gfs-deterministic-natl_wide-vort500_z500-7816000.thumb.png.304d6e0b077be9c9b1b1bc4eb8c0c445.pngPPVM89.thumb.gif.323e775908e4ec807e10b5b426609b8e.gifgfs-deterministic-uk-t2m_c_max6-7837600.thumb.png.dd386128129bccbf86c4bffe2030bbb2.png

The trough will bring cloud and some patchy rain to the NW on Sunday and showers may well be more frequent in the south west but dry and sunny again elsewhere

PPVO89.thumb.gif.84afe10a767632b5e56287789f9d623b.gifgfs-deterministic-uk-precip_6hr_inch-7909600.thumb.png.2790597782332fc0ae90a4a3d2158f83.pnggfs-deterministic-uk-t2m_c_max6-7924000.thumb.png.6d54dd9b9c95dbc2b43fa68d14057750.png

Edited by knocker
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Next week is a work in progress so wise not to venture too far so in a nutshell the gfs version for the next three days,

Our trough continues east and develops over southern Scandinavia as it phases with the main trough  This partially opens the door to the Atlantic but the subtropical high and the trough over the western Mediterranean are still players as this pans out and it raises doubts as to how quick any unsettled weather from the west will arrive over the UK

gfs-deterministic-nhemi-z500_anom-8075200.thumb.png.b55c31a908e5b0aa5f8fabe8d25ba955.pnggfs-deterministic-nhemi-z500_anom-8161600.thumb.png.efcf0c5f6da1b18137f4c20bb0a3e781.pnggfs-deterministic-nhemi-z300_speed-8161600.thumb.png.567b533630f9f7d232f1b49a7a65b0ae.png132.thumb.png.97fb705df2fefe37cc1c78c997959454.png156.thumb.png.cb8158ad31fe06578d21ca011bb58fd3.png180.thumb.png.c0996ce313c110ee1d7a4e2d4748ce4b.png

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The ecm is not quite as keen to track the trough east and phase it with the main trough thus the Atlantic door is opened a tad wider and a developing wave tracks east over the UK by Weds

ecmwf-deterministic-natl_wide-vort500_z500-7988800.thumb.png.c3e363d44bf53b72079eb53b04e085fc.pngecmwf-deterministic-natl_wide-vort500_z500-8075200.thumb.png.a412dedc1d92cbe2071cbd70864597ee.png

132.thumb.png.daeb6c41a46dabd49bf78dc0064deec2.png156.thumb.png.11d7e8fe3fa7992c746e096f0104bd2e.png180.thumb.png.97555fcefba60e4c88203cb1beede3c2.png

 

Edited by knocker
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3 hours ago, knocker said:

gfs-deterministic-uk-t2m_c_max6-7664800.thumb.png.2b5ae61194845ee4c2084602b33029e2.png

 

 

Good to see these are as accurate as ever. Going for 19-20c max temperatures tomorrow, when 24-25c is likely to be achieved. Is there a reason these consistently under-do maximum temperatures??

 

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It is rather a tad premature to accuse them in being wrong 36 hours prior to the event but the short answer to your question is that I'm afraid it's  above my pay grade. I assume everyone is aware of the vagaries of model max temps forecasts and don't put implicit faith in them but, short of not posting them at all, I'm not sure what else one can in a model discussion thread. Do you find there are similar problems with min temps, air not grass, as topography might be part of the equation?

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