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Paul

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Posted
  • Location: Camborne
  • Location: Camborne

The gfs has a wintry day over Scotland on Saturday with snow on the high ground before more general frontal rain and strong winds sweep north east through the country overnight courtesy of a deep trough in mid Atlantic

gfs-deterministic-natl_wide-z300_speed-0601600.thumb.png.bee18ba98ee70959754c9578af538293.png120.thumb.png.597666a09ed80a965d5344f5f074f960.png138.thumb.png.72b1c423c020740f7e6a0d7c9a4dfeae.png

 

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Posted
  • Location: Camborne
  • Location: Camborne

I was going to have a closer look at frid > Sunday with the gfs but it's so much at variance with Exeter by midday saturday I thought best to wait for the ecm

PPVM89.thumb.gif.1bc771ce7f03578d4e39994b27d355a0.gifPPVO89.thumb.gif.71ca0517612ec66e6203f8e1f6adfe64.gif106.thumb.png.e906d40840e27e6c78e9829f9e1464d7.png

And certainly by midday Friday not bad agreement continuing through Saturday, albeit Exeter makes a tad more of the wve west of Ireland, and then on Sunday the ecm brings further fronts north associated with the main low to the west It's all rather complex

84.thumb.png.6048907d90b2833353890258195fe885.png108.thumb.png.4e6eea7effc6b9633dbc230d794a84ab.png132.thumb.png.07826e0dfd08d835a0acc4c30772fe0a.png

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Posted
  • Location: Camborne
  • Location: Camborne

A glance at the EC weeklies update for the last week of Feb and the first week of March

22 > 29

Aleutian ridge adjacent to the main lobe of the tpv over northern Canada with the associated trough orientated into the north west Atlantic.

Quite a strong westerly upper flow exiting the eastern seaboard across the Atlantic but the subtropical high is flexing it's muscles a tad over Europe with some positive anomalies with the UK on the periphery of this.

Thus the flow abating in the east and although still changeable the indications are of much of this being concentrated in the north

Temps above average

ecmwf-weeklies-avg-nhemi-z500_anom_7day-2934400.thumb.png.dbc8f66fd311fd93cd70f4ae9fbeb5b4.pngecmwf-weeklies-avg-eur-t2m_c_anom_7day-2934400.thumb.png.7d729db7f2a6ef9c2025a78cda239b7b.pngecmwf-weeklies-avg-eur-precip_168hr_inch-2934400.thumb.png.abb0b61b0250137d98405c330e66eef9.png

01 > 08

Less amplification of the Aleutian ridge and a subsequent adjustment to the orientation of the main tpv lobe and thus more influence of the subtropical high in the eastern Atlantic. Thus a generally more settled period for the UK would be the percentage play

ecmwf-weeklies-avg-nhemi-z500_anom_7day-3625600.thumb.png.0b5af486a9cd2879e250de9159371637.pngecmwf-weeklies-avg-eur-t2m_c_anom_7day-3712000.thumb.png.92ee2859cee23cd991d0f55af9349a1b.pngecmwf-weeklies-avg-eur-precip_168hr_inch-3712000.thumb.png.eba5bc30a2c6d801f7d04890301656dd.png

 

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Posted
  • Location: Camborne
  • Location: Camborne

Prior to, and during, the ext period the man mean anomalies have a realignment of the tpv with the main lobe over northern Canada which facilitates further amplification of the Atlantic subtropical high  The precise amplitude and orientation of this and the trough to the east are fairly critical but the percentage play is a period of more settled weather with temps around average but that does smooth over diurnal variations

ecmwf-ensemble-avg-nhemi-z500_anom_5day-1379200.thumb.png.67dc946ba3d86940fd92ace6144e2d41.pnggfs-ensemble-all-avg-nhemi-z500_anom_5day-1379200.thumb.png.151e63d4a5d13e5132ef14f10b67e5d2.png814day_03.thumb.gif.c7f961f1e19e7bf52ab4a1cedc8a914a.gif

ecmwf-ensemble-avg-eur-t2m_c_anom_5day-1379200.thumb.png.ab12e1fc923407f5b81d9006448ab249.pngecmwf-ensemble-avg-eur-precip_168hr_inch-1379200.thumb.png.3d73bf04d14ee3b55fd46f21d1c55b9e.png

As an aside some clarification vis the above tpv comment

tpv.thumb.JPG.f6b34efa13be306a64c9d57db1c26eb6.JPG

 

Edited by knocker
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Posted
  • Location: Camborne
  • Location: Camborne

On Saturday the UK continues to be effected by two energy flows with rain and strong winds over Scotland before fronts from another system track up from the south west bringing more general rain and strong winds overnight and through Sunday

gfs-deterministic-nhemi-z300_speed-0558400.thumb.png.ea5ed926de7e62d8da486540337ad3ed.pnggfs-deterministic-nhemi-z300_speed-0623200.thumb.png.5d873cfc0c9888f0a03e02164c2b4b58.png

96.thumb.png.35cd814bc1f75cc1bc882dc7fdb924de.png114.thumb.png.e6ab44f7d9fdf68101bf47d484749f8d.png

And by Tuesday another bout of NH amplification kicks in and a more meridional jet

gfs-deterministic-nhemi-z500_anom-0817600.thumb.png.df4e0ec7e96e3f0f74372dc21d7d729f.png

 

 

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Posted
  • Location: just south of Doncaster, Sth Yorks
  • Location: just south of Doncaster, Sth Yorks

Just a quick post re changes possible in upper air flow 6-14 day period.

Take a look at the 500 mob anomlay charts. They offer a reasonable pattern in that period in my view.

The main trough is shifted west and thus allows a coldish plunge of air into Europe. Not clear yet how much of an effect this may have on the UK just yet.

10 cm of the whit stuff today!

Sorry

 

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Posted
  • Location: Camborne
  • Location: Camborne
1 hour ago, johnholmes said:

Just a quick post re changes possible in upper air flow 6-14 day period.

Take a look at the 500 mob anomlay charts. They offer a reasonable pattern in that period in my view.

The main trough is shifted west and thus allows a coldish plunge of air into Europe. Not clear yet how much of an effect this may have on the UK just yet.

10 cm of the whit stuff today!

Sorry

 

I was looking at the EPS earlier John and it currently is indicating the subtropical high losing amplitude

ecmwf-ensemble-avg-nhemi-z500_anom_5day-1422400.thumb.png.2ecd51c9c4767014a5b15619e807c1f5.pngecmwf-ensemble-avg-nhemi-z500_anom-1508800.thumb.png.c402061fd9dff2f4c83e64be7d442c2b.png

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Posted
  • Location: Solihull, Midlands. (Formerly DRL)
  • Weather Preferences: Sunshine, thunder, hail & heavy snow
  • Location: Solihull, Midlands. (Formerly DRL)

Just seeing the GFS 18Z pub run, got a feeling there will be toys to clear up in the main Model thread. 

DBF4CCA9-84D9-41FC-A2FD-4D0CD6FDD727.thumb.png.b8f298142fc1535bb58aeb8c171a8d22.png95F365BD-B29A-47D0-8A19-2692945B5E39.thumb.png.f161b06fbb801360b62305bf3ed1bb0f.png3365D540-7FC0-4587-8F82-7828AA316BAE.thumb.png.01e58aa2f8f761344c3016c4a61bdcd6.png
Just one run from run model and can imagine there will be further ups and downs. But the Northerly for early to mid next week is replaced with more of a flatter North-Westerly flow. The Southern UK High, though, would offer some drier and brighter weather for a time. A theme the GFS continues deeper into its run at 240 hours and Low Pressure systems brushing over the top.

9C899B3A-EF66-4359-8339-5381EC8F89DE.thumb.png.96d5d45a3941c80a2bbfac40593014ad.png

Much as I would love some Northerlies, feel as though a bit more of a flatter pattern with High Pressure close by/over the UK at times is probably more likely (or at least any Northerlies being temporary affairs). 

Edited by DiagonalRedLine
Removing extra duplicate chart
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Posted
  • Location: Camborne
  • Location: Camborne

The North Atlantic 500mb and surface analysis for midnight

ecmwf-deterministic-natl_wide-z500_anom-0256000.thumb.png.64b949c7eeb6bfce681591919cb4124d.pngPPVA89.thumb.gif.a1ff2704b8b538cf4b7c881482541310.gif

Still some showers around over N. Ireland and western Scotland this morning but they will quickly fizzle out only to be replaced by frontal rain by 0900 that will move east and as far south as the north Midlands though the rest of the day. It will tend to die out this evening but another band will track north east over western Scotland during the latter part of tonight

PPVE89.thumb.gif.73aded778e0bd4b2026ea7be04bb8576.gifprecip_d02_15.thumb.png.834d372c9946e78df3e5b04a2d9787a5.pngprecip_d02_21.thumb.png.aeafaa80133106380048d2b550ac625c.pngprecip_d02_27.thumb.png.1662386a1e82bc23eec0a92191451247.pngprecip_d02_33.thumb.png.935f100e81faf19403a6027a95577c55.png

Midday Thursday has an intense low just north west of Scotland so windy with some heavy rain here whilst further south dry but mainly cloudy

PPVG89.thumb.gif.2832abe408fe535af38fb446f0d00553.gifprecip_d02_40.thumb.png.becd2f52b0d97a7c351c476ff6ad59ce.pngprecip_d02_44.thumb.png.781cc4ce8f501c95289c3309e1d679b6.png

This low quickly tracks north but as can be seen further troughs have tracked into the Atlantic, courtesy of the two upstream energy flows, and by midday Friday there is a deep surface low west of Ireland whilst the associated fronts bring quite strong winds and rain to some areas and at the same time introduce much warmer air

ecmwf-deterministic-natl_wide-vort500_z500-0493600.thumb.png.9bd32fe65dd673befe7e958518451a6f.pngPPVI89.thumb.gif.b9c94ee707ca5cbc7014cc26312bec17.gifPPVJ89.thumb.gif.18eec716e71d9d716764f0087ed28c20.gif

gfs-deterministic-uk-precip_3hr_inch-0461200.thumb.png.22681d42ade475adbbfb0e87b739d9d0.pnggfs-deterministic-uk-precip_3hr_inch-0493600.thumb.png.aff77951380e3acae99b263208eabfd7.pnggfs-deterministic-uk-t2m_c_max6-0493600.thumb.png.4fe2edb4529b12c5cae3c9b969f7fa65.png

Over the next 24 hours the low slowly fills and drifts north east to be over northern Scotland 975mb by midday Saturday thus quite a windy day, particularly in the north, with intermittent rain

PPVK89.thumb.gif.549601d2a7676ff6e498ac3667798009.gifPPVL89.thumb.gif.1055af7139fd436e2cc73bd7b544f4ec.gif

gfs-deterministic-uk-precip_6hr_inch-0580000.thumb.png.0aa6fef5a52b55af7e9ebf3e2770ac8c.pnggfs-deterministic-uk-t2m_c_max6-0580000.thumb.png.a865ae28c382373fbd3a4e33ae07d09d.png

This low also clears quickly but another one sweeps up from the south west to be west of Ireland and the associated frontal system brings more rain and even warmer air on Sunday

PPVO89.thumb.gif.a44ee9b1141cd067d16f3c999930e410.gif

gfs-deterministic-uk-precip_6hr_inch-0634000.thumb.png.c42c4a6be1b0d80c337c196720f261cd.pnggfs-deterministic-uk-precip_6hr_inch-0655600.thumb.png.7f2d1e51379b77b8d9ad30b290fc1fac.pnggfs-deterministic-uk-t2m_c_max6-0666400.thumb.png.567da21d05a6f69c8af34f257271f062.png

 

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Posted
  • Location: Camborne
  • Location: Camborne

In the 5-10 period the expected amplification takes place but there is still a lot of aest bound energy around

ecmwf-deterministic-nhemi-z500_anom_5day-1120000.thumb.png.a856b5daefaa12ecc9e8e715d4914211.pngecmwf-deterministic-nhemi-z300_speed-0774400.thumb.png.a0688870642d88627d2e9a2dc27d0ee1.pngecmwf-deterministic-nhemi-z300_speed-1120000.thumb.png.02b99c110c2c9110a57ef2b7fa81b3b7.png

Some selected ecm surface charts tat should illustrate this this reasonably well as the detail a tad pointless at this range

144.thumb.png.0eb78cf164316ded0c66ffa97aec74b0.png168.thumb.png.6b50475b45d4bc47f674fda50f782408.png192.thumb.png.ec9cb2252f31463f9df33ffbc347c79a.png216.thumb.png.364edd780858878d4510a766845155f3.png

Edited by knocker
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Posted
  • Location: Camborne
  • Location: Camborne

The ext mean EPS mean anomaly this morning continues to suggest that the realignment of the tpv is starting to dominate proceedings. Thus the subtropical high having less influence with a likely N/S split vis the weather

ecmwf-ensemble-avg-nhemi-z500_anom_5day-1465600.thumb.png.212b30ce025783922d2ec1f4a1a8430c.pngecmwf-ensemble-avg-eur-t2m_c_anom_5day-1465600.thumb.png.ea442359ba08f0941347a570ae9215af.png

The strat this morning

ecmwf-deterministic-nhemi-z10_anom-1120000.thumb.png.a8f95c4389870695de2bba153b03f25c.pngecmwf-deterministic-nhemi-z30_anom-1120000.thumb.png.8e88630b924520ee4832c91c5c3c15f1.png

 

Edited by knocker
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Posted
  • Location: Camborne
  • Location: Camborne

The movement of the upper troughs north  east America > North Atlantic that initially amplifies the subtropical high downstream and then flattens it with a very pumped up jet According to the gfs

gfs-deterministic-natl_wide-vort500_z500-0817600.thumb.png.8f041842ff748d34816eca71b9bbfecd.pnggfs-deterministic-natl_wide-vort500_z500-0904000.thumb.png.1e34ea4ef27f57dd09cdef8fda03b6ce.pnggfs-deterministic-natl_wide-vort500_z500-0990400.thumb.png.feaac9aa7fe6f136f46c7f6e9c5621cd.png

gfs-deterministic-natl_wide-z300_speed-0990400.thumb.png.d4dcca5e94254a33ccbaa281dc4dd8d9.png

Edited by knocker
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