Jump to content
Snow?
Local
Radar
Cold?
IGNORED

Models, teleconnections and nowcasting


Paul

Recommended Posts

Posted
  • Location: Camborne
  • Location: Camborne

The ext GEFS mean anomaly continuing the trend that has been indicated recently with the strong ridge over NW North America weakening the Canadian vortex lobe in favour of the main lobe in the the vicinity of Franz Joseph Island.Effectively, although still a fairly strong westerly flow across the Atlantic, it does away with the negative anomalies and with the subtropical high still retaining some influence a drier and less unsettled period maybe beckons, albeit with a N/S bias

gfs-ensemble-all-avg-nhemi-z500_anom_5day-9953600.thumb.png.5deba764b6a814af189b05e3e9f1581f.pnggfs-ensemble-all-avg-eur-t2m_c_anom_5day-9953600.thumb.png.3c7dc40e247d3cfc1996cf418480e46a.pnggfs-ensemble-all-avg-eur-precip_168hr_inch-9953600.thumb.png.66dff93f7250b62d23e6ef28f22f21a3.png

And the GEFS strat data

gfs-ensemble-all-avg-nhemi-z10_anom-0040000.thumb.png.0c8ae0c72c0a9ee8b9a36f91ab120ab2.pnggfs-ensemble-all-avg-nhemi-z50_anom-0040000.thumb.png.fbaf4851ec14d8f5e13bda14d2db862f.png

Edited by knocker
  • Like 4
Link to comment
Share on other sites

Posted
  • Location: South Oxfordshire
  • Location: South Oxfordshire
6 minutes ago, knocker said:

The ecm det 5-10 not dissimilar in some ways to the ext GEFS

ecmwf-deterministic-nhemi-z500_anom_5day-9608000.thumb.png.59770432e68b73d515b61cc1ddb6ca31.pngecmwf-deterministic-nhemi-t850_anom_5day-9608000.thumb.png.b49cb2e5e6962050d560d5c708416960.png

Forgive my lack of knowledge, but rather than any ssw event there's a squeeze on the polar vortex by height rises mid latitude, which in the shortterm give us the warmer temp anomalies, does it cause a split? Thanks, Griff. 

(there's a chance I'm talking out of my rear end and making all this all up) 

Edited by Griff
Link to comment
Share on other sites

Posted
  • Location: Camborne
  • Location: Camborne
26 minutes ago, Griff said:

Forgive my lack of knowledge, but rather than any ssw event there's a squeeze on the polar vortex by height rises mid latitude, which in the shortterm give us the warmer temp anomalies, does it cause a split? Thanks, Griff. 

It rather depends which strat output you look at but the spv looks in pretty reasonable shape.with no split. Out warm anomalies have been down to the  trop pattern

EDIT

Just to add @Griffif you talking about the tpv then yes the Alaskan ridge does come into play

Edited by knocker
  • Like 3
Link to comment
Share on other sites

Posted
  • Location: ipswich <east near the a14> east weather watch
  • Location: ipswich <east near the a14> east weather watch
On 05/12/2019 at 16:15, jordan smith said:

A closer look at ecmwf earlier output for Sunday. 

Qpo3nij5sy.thumb.gif.a206860f85b77988772f4fd51a6dd16d.gif

Very windy especially for the West with very strong gusts. Subject to changes ofcourse.

EzrkoVfR5G.thumb.gif.2c1b00552bc12e6b76dd73780f25b957.gif

Tuesday  looking wild to say the least

  • Like 1
Link to comment
Share on other sites

Posted
  • Location: Camborne
  • Location: Camborne

No surprises with the ext EPS. Ridge NW North America; more intensive vortex lobe northern Russia as the Canadian one weakens, Thus a much more benign Atlantic as the trough withdraws with the subtropical high being quite influential in the east. This would indicate a more settled and drier period for most. Still downstream differences with the GEFs which maybe a timing issue

ecmwf-ensemble-avg-nhemi-z500_anom_5day-9953600.thumb.png.0ef3f4a69ff29b0340b382c7a48c7c32.pngecmwf-ensemble-avg-eur-t2m_c_anom_5day-9953600.thumb.png.b692a3499bd4de1704735d729175b04e.pngecmwf-ensemble-avg-eur-precip_168hr_inch-9932000.thumb.png.ae51c585b88120d59570de9884fadaa9.png

 

 

  • Like 1
Link to comment
Share on other sites

Posted
  • Location: Camborne
  • Location: Camborne

The North Atlantic 500mb and surface analysis for midnight

gfs-deterministic-natl_wide-z500_anom-8787200.thumb.png.cc89a0f937182381a1c4e82b2d7d7d23.pngPPVA89.thumb.gif.41cf15501927c831746b00762d96d3c6.gif

Still some showery rain lingering in some areas at the moment but this should clear quite quickly leaving sunny intervals and the odd shower for most but more frequent showers in western Scotland and perhaps N. Ireland.These could of snow and sleet to relatively low levels as there is quite a N/S temp spread

PPVE89.thumb.gif.41d9864bcc653f78fcd3a159dec76dc5.gif2mtemp_d02_21.thumb.png.ad098cf878c019b5f6bdf68dfed1c9c3.pngmeanreflec_d02_24.thumb.png.e514387585969d95e16dd80beb2eb9ae.png

Clear in most places tonight but the showers continuing over Scotland where it will also be quite windy and later another band will track east across the south courtesy of a stray occlusion. But note some rapid cyclogenisis is taking place out in the Atlantic and by midnight the low is 954mb west of Ireland.

gfs-deterministic-natl_wide-z300_speed-8895200.thumb.png.636dede4e351084a09d6bc16425664e0.pngPPVG89.thumb.gif.716ce834903e0571b82c223b67104655.gifprecip_d02_32.thumb.png.fdf48f73544894d963f5e1593edd0392.png

By midday Monday the low is down to 941mb west of Ireland and it is still deepening as it tracks slowly NNE and the associated occlusion will bring heavy rain as it sweeps east across the country but more to the point, there will be some very strong winds along the front and later across N. Ireland as the low slips past to the NW. I wont waffle on about this as there is a dedicated thread

PPVI89.thumb.gif.de3b081bd2c1a7b3b4b684f3fe61de17.gif2mtemp_d02_45.thumb.png.2f6201ed349f9a2c16d9381f2b589a10.pngprecip_d02_48.thumb.png.04042738dafe8427a6a0707437b7dba4.png

sfcgust_d02_42.thumb.png.9486371b9e3443829997545155becae4.pngsfcgust_d02_45.thumb.png.aca9ce4408876f82937383eccdb5caf2.pngsfcgust_d02_48.thumb.png.d61319809e005dc2b2e1995e5de748ca.png

The front will clear to the east Monday evening but another low is developing at the base of the upper trough to the south west and this develops and tracks  north east through Tuesday bringing more heavy rain and strong winds to the south and perhaps some snow to quite low levels in the north

gfs-deterministic-natl_wide-vort500_z500-9003200.thumb.png.8a7d6240585b2fa50bd392cabb49a934.pngPPVJ89.thumb.gif.5d661e380ef5b7e6bc5b47db3e4688a0.gifPPVK89.thumb.gif.acf33f80994fda8ac829c7d16f3ccd57.gif

gfs-deterministic-uk-precip_6hr_inch-9024800.thumb.png.56869e480539087c3d860b7024e5cf66.pnggfs-deterministic-uk-t2m_c_max6-9024800.thumb.png.8c86c723ad110fa01e99219f9be35687.png

Again the system clears quickly to the east resulting in Wednesday being a day of sunny intervals and showers. But these will be mainly concentrated over western regions with longer spells of rain over Scotland where it will also be very windy

PPVM89.thumb.gif.283be8cd6310483169679fd4b2eaefa9.gifgfs-deterministic-uk-precip_6hr_inch-9111200.thumb.png.058e897b100809457844df2ead840165.pnggfs-deterministic-uk-t2m_c_max6-9111200.thumb.png.4392cd6aab0918e7936d945fab995e14.png

But by Thursday yet another wave has developed to the south west and has tracked NNE to be over Ireland by midday and the associated fronts will bring further heavy rain and strong winds to most areas during the day

PPVO89.thumb.gif.788d092d3d5d290db9c08485114e8235.gifgfs-deterministic-uk-precip_6hr_inch-9176000.thumb.png.bde6820697449ceff507f7a1bb8d8032.pnggfs-deterministic-uk-t2m_c_max6-9111200.thumb.png.20c5df3150677bc30932cdc7f06c9f76.png

 

  • Like 7
Link to comment
Share on other sites

Posted
  • Location: Camborne
  • Location: Camborne

According to the gfs it continues changeable into next weekend

144.thumb.png.4e2dac679c05c14485a4e8b626058418.png168.thumb.png.5b88cbe4771cc167ab01c6dbc45b7b42.png

But the much indicated pattern change is now approaching and there are no surprises with the ext GEFs mean anomaly

Upstream pretty much as previously discussed with a fairly strong upper flow across a now relatively benign Atlantic, where the subtropical high has gained some traction, but abating in the east where it diverges a tad to low pressure over the Mediterranean. Certainly a more settled period than of late but still tending towards a N/S bias

gfs-ensemble-all-avg-nhemi-z500_anom_5day-9996800.thumb.png.ba417543d9832f6230f4c3fda09d1379.pnggfs-ensemble-all-avg-eur-t2m_c_anom_5day-9996800.thumb.png.e80254f153cba9ef4235333cdc575035.pnggfs-ensemble-all-avg-eur-precip_168hr_inch-9996800.thumb.png.31a15bb070fbadd4c192f01fdc657fca.png

 

  • Like 3
Link to comment
Share on other sites

Posted
  • Location: Camborne
  • Location: Camborne

The ecm changeable next weekend but tending towards more influence from the subtropical high before some intense amplification right at the end that needs to be put on hold until checked with the EPS

ecmwf-deterministic-nhemi-z500_anom_5day-9651200.thumb.png.7e7c9a6065efa0f5dd90e08fdca325a5.pngindex.thumb.png.b2cdd8b193ee5bd6139924972d9e2973.png168.thumb.png.40990e07c99209b65203e61cd2388d15.png192.thumb.png.4aa659d7c96e5ef1e0a9028be15d1714.png

  • Like 3
Link to comment
Share on other sites

Posted
  • Location: Camborne
  • Location: Camborne

The EPS has the pattern change getting underway quite early between t144- 168 with the ejection south of the Canadian vortex lobe which initiates subtropical high amplification in mid Atlantic But this then subsides and the ext mean anomaly has a familiar look to it.

Ridge NW North America adjacent to the now weak Canadian lobe with the main tpv in the vicinity of Franz Joseph. A strong westerly upper flow exiting the eastern seaboard but abating around the now subsiding subtropical high and diverging to some extent to the Mediterranean low pressure Portending a drier and more settled period, particularly in the south but maybe heading for a flatter zonal flow? We shall see

ecmwf-ensemble-avg-nhemi-z500_anom_5day-9996800.thumb.png.ae1162ed4dcadb58faabec3e75551de5.pngecmwf-ensemble-avg-eur-t2m_c_anom_5day-9996800.thumb.png.38307b5c49f672da9a46e2ed2f39061f.pngecmwf-ensemble-avg-eur-precip_168hr_inch-9996800.thumb.png.069a08198a3e6370d5131fbe2425e7ed.png

 

 

  • Like 4
Link to comment
Share on other sites

Posted
  • Location: Camborne
  • Location: Camborne

The start of this much heralded pattern change now appears to get underway with a lobe of the vortex dropping south into the western Atlantic initiating downstream amplification and the deconstruction of the UK trough creating a cut off upper low over the Mediterranean

gfs-deterministic-nhemi-z500_anom-9327200.thumb.png.9f2f0edc2e5a0d8f50e08beb3eea94ca.png

And from here we move into the next phase the detail of which awaits confirmation

144.thumb.png.1d4f1efca3f719e705f36c57ec92ec59.png168.thumb.png.6bcbf3fb406fd11f0d0c3ddf3f150019.png192.thumb.png.8515aff4bcef7adc5ea9c29373a7545d.png

 

 

  • Like 2
Link to comment
Share on other sites

Posted
  • Location: Camborne
  • Location: Camborne

An overview of the possible transition with the GEFS anomalies.this evening. These illustrate the ridge over NW North America doing some nasty things the Canadian Vortex lobe which results in some downstream amplification which subsides in the ext period, although it does established low pressure in the Mediterranean area, This could indicate a more settled period before a tad changeable again

gfs-ensemble-all-avg-nhemi-z500_anom_5day-9694400.thumb.png.c8b0b85736eae99091da91575ba7400b.pnggfs-ensemble-all-avg-nhemi-z500_anom_5day-0040000.thumb.png.9e917e34369c01d7c400936681e059f2.png

gfs-ensemble-all-avg-eur-t2m_c_anom_5day-0040000.thumb.png.0277971f376dd26739796b8212dc9fb0.pnggfs-ensemble-all-avg-eur-precip_168hr_inch-0040000.thumb.png.f0ebd67a7984b9b268bee8e0b9fed873.png

Edited by knocker
  • Like 1
Link to comment
Share on other sites

Posted
  • Location: Camborne
  • Location: Camborne

After the initial amplification the ext mean EPS settles into a pattern in the same ball park as above albeit retaining a tad more influence from the subtropical high in the vicinity of the UK  If anything like this pans out it would indicate a more settled period but the concern would still the continuing flattening of the amplification

ecmwf-ensemble-avg-nhemi-z500_anom_5day-0040000.thumb.png.6835f3a89b4b504a183cd65778b60627.pngecmwf-ensemble-avg-eur-t2m_c_anom_5day-0040000.thumb.png.9c1cd9b9cdd1c6af9df8ccc7f25519aa.pngecmwf-ensemble-avg-eur-precip_168hr_inch-0040000.thumb.png.8b66ffbc211a7572370c6f66d3947f09.png

Edited by knocker
Link to comment
Share on other sites

Posted
  • Location: Camborne
  • Location: Camborne

The North Atlantic 300mb wind field and surface analysis for midnight and current satellite image

gfs-deterministic-natl_wide-z300_speed-8873600.thumb.png.1437138ba4ea82cc287c835d97fd5401.pngPPVA89.thumb.gif.e951e2569494c94369455a67ae2684df.gifmeteosat-msg_ir108_overlay-ne_10m_coastline_overlay-ne_10m_admin_0_boundary_lines_land.thumb.jpg.26fb694d9cbbabe69bdae9ef9f6cd9f4.jpg

Everyone is obviously aware of Brendan tracking NNE west of Ireland and the strong winds and band of heavy rain, followed by heavy showers, expected today as the associated front(s) move east across the country so without further ado:

PPVE89.thumb.gif.1a911a91a7882adec592c5e4e421cf2f.gifsfcgust_d02_17.thumb.png.3823997f447239a7212b82497e889d14.pngsfcgust_d02_20.thumb.png.da26644f87e10e1e48f659505effe31c.pngsfcgust_d02_24.thumb.png.42fccae36a56aa048ffa2ee6c55e3310.pngsfcgust_d02_27.thumb.png.eca08993bbd312c658ae82b1168091e3.pngmeanreflec_d02_18.thumb.png.30fb399664644f50b4c451aa4bafabe2.pngmeanreflec_d02_21.thumb.png.e096b320b155db3b5138430701bf422a.pngmeanreflec_d02_24.thumb.png.4ce6baa90a139ff75b7b51dd97f14ae5.pngprecip_d02_28.thumb.png.2ec86d0ae57a364406e0fe820141fddf.png

The rain and gales clearing tonight, but the showers and strong winds, with snow to fairly low levels,,will continue in the NW

PPVG89.thumb.gif.660ab45b782adffc1b7cd9102eccd9dc.gif

Quite a bright start for most on Tuesday but a frontal wave has developed to the south west and this deepens and tracks north east bringing more rain and strong winds to much of England and Wales from late morning and there could well be some snow down to fairly low levels in the north preceding the front

PPVI89.thumb.gif.681c229c3a716716fef787d6bf8caa43.gif2mtemp_d02_45.thumb.png.bedcd606b0121a95aed24f962d63101e.pngprecip_d02_45.thumb.png.f4958f8473cc436ecbe2a0933dd341c0.png

The rain clears most places overnight but not N. Ireland and western Scotland which are still effected by the remnants of Brendan so still some rain and quite strong winds here. But yet another low is developing away to the south west

PPVJ89.thumb.gif.d87ab6dc63f6e37b7ad46f63b6ba072f.gifPPVK89.thumb.gif.57f5e3c8f72c4c7e44b29eb08aa7c78b.gif

gfs-deterministic-uk-precip_6hr_inch-9089600.thumb.png.d02c7c66ebbc250951df5109f76db3e6.pnggfs-deterministic-uk-precip_6hr_inch-9111200.thumb.png.c07f316f62eb953a1c3e868df0e19d47.pnggfs-deterministic-uk-t2m_c_max6-9111200.thumb.png.65c106c86dca4694397ed97109be0905.png

This low then tracks NNE along the west coast of Ireland and initiates some quite strong winds and, temporarily, some quite warm air, and more heavy rain as the associated cold front tracks east across the country

PPVM89.thumb.gif.db56128d17e3786389e1849bd6bd086f.gifgfs-deterministic-uk-precip_6hr_inch-9197600.thumb.png.8d5012bf898b215e3fbcc6dd00421f6d.pnggfs-deterministic-uk-t2m_c_max6-9197600.thumb.png.4e1bc5f2efdfb98fc34851d7425cdc1a.png

Most of the rain clears overnight resulting in Friday being a showery and cooler day

PPVO89.thumb.gif.80ddcae01d7eb82f602f8bbb87a5f0b3.gifgfs-deterministic-uk-precip_6hr_inch-9284000.thumb.png.47f8ee861c7d61ca104abf75e1a72fd2.pnggfs-deterministic-uk-t2m_c_max6-9284000.thumb.png.219bdb62a0a39fe03156a2325343d0fe.png

 

  • Like 7
Link to comment
Share on other sites

Posted
  • Location: Camborne
  • Location: Camborne

We have now reached the transition previously discussed where a lobe of the tpv drops south in the western atlantic initiating downstream amplification and the disruption of the UK trough which creates a cut off low in the Mediterranean area. Hopefully this is also the start of a more settled period of weather as the subtropical high becomes more influential

gfs-deterministic-nhemi-z500_anom-9348800.thumb.png.91303259562047e9f7268b2b06b05776.pnggfs-deterministic-nhemi-z500_anom-9435200.thumb.png.fde995fe24f2a628f75dd8eece282dd1.png

132.thumb.png.38c81d88b9984a0529d8db37d8ff4588.png156.thumb.png.20c647af7317798f0409e52785e15376.png180.thumb.png.a1d641f6d20713c23e990df52dc89107.png

  • Like 2
Link to comment
Share on other sites

Posted
  • Location: Camborne
  • Location: Camborne

The NH profile pretty much as expected with the GEFS ext mean anomaly this morning so just a closer look at the North Atlantic. And as can be seen the subtropical high quite influential over the UK which would certainly portend a more settled period

gfs-ensemble-all-avg-natl_wide-z500_anom_5day-0083200.thumb.png.43019a5ee51987c340e6e2f8899fdcb3.pnggfs-ensemble-all-avg-eur-t2m_c_anom_5day-0083200.thumb.png.f4ef08e15874329192965459aebf1ce5.pnggfs-ensemble-all-avg-eur-precip_168hr_inch-0083200.thumb.png.26e6f4b61a4491c4dab4a521871a0dee.png

  • Like 3
Link to comment
Share on other sites

Posted
  • Location: Camborne
  • Location: Camborne

The ecm also has the transition over the weekend, the only difference being it  makes much more of the developing low away to the sooth west that eventually becomes the cut off low

ecmwf-deterministic-nhemi-z500_anom-9348800.thumb.png.dea1bb4c6eb634edcec62f604a98dfad.pngecmwf-deterministic-nhemi-z500_anom-9435200.thumb.png.754d412f7524318b850f25809f78999a.png

Capture.thumb.JPG.33d7fd86d455b127f028792f62c3a919.JPG84.thumb.png.c9188bfc97b606a6bcd670f9ef14d840.png156.thumb.png.3a6d02eb23674a96a184776d40003066.png

And the overview of the last half of the run

ecmwf-deterministic-nhemi-z500_anom_5day-9737600.thumb.png.81dfe474c17852cf7c2518792e1d5307.png

 

  • Like 3
Link to comment
Share on other sites

Guest
This topic is now closed to further replies.
×
×
  • Create New...