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Paul

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Posted
  • Location: Camborne
  • Location: Camborne

As the tpv lobe gets itself into gear some very windy and wet weather likely over the weekend with severe gales, as a front sweeps through Sat/Sunday

gfs-deterministic-natl_wide-z500_anom-1195600.thumb.png.53f3127fefd65ac4fd30ab1e7972b8e3.png132.thumb.png.b1b6be0ccfb9bcae097cfa70ddd00b9b.png114.thumb.png.44d4e19282b9e73505d73f5f90c81f8e.png

gfs-deterministic-uk-gust_kt-1206400.thumb.png.c5f8983459c94638467fa627680f28fd.pnggfs-deterministic-uk-gust_kt-1260400.thumb.png.2de900d6fb99d02267ea5600ab2bdbe0.pnggfs-deterministic-uk-gust_kt-1271200.thumb.png.91387841c389f42164ccc68e77898d93.png

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

The problem here, merely as I see it of course, is that the Atlantic is one big baroclinic zone and the ecm has the rapid cyclogenisis further south over the weekend but still resulting in some very windy and wet weather, particularly in the north. Obviously the detail still to be resolved

ecmwf-deterministic-natl_wide-vort500_z500-1163200.thumb.png.e95c7b9804e59666bedc3751d23ac4e6.pngecmwf-deterministic-natl_wide-vort500_z500-1206400.thumb.png.bbbca8a074092a389b02c2843839c975.pngecmwf-deterministic-natl_wide-z300_speed-1206400.thumb.png.7f93f12ca91cb27a08d34f09c01d9695.png108.thumb.png.7986793ed07f11750e74a7bfa223e390.png120.thumb.png.55cae0d55c614cb4556f14b86f5d54bf.png

ecmwf-deterministic-uk-gust_kt-1184800.thumb.png.0873dd23ffe253fc5d79cdbb6e4b9470.pngecmwf-deterministic-uk-gust_kt-1260400.thumb.png.621db731c8659ef794bfbf64b1abe84d.pngecmwf-deterministic-uk-gust_kt-1271200.thumb.png.91777161992137ddaf3263f20fe3cf21.png

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

High pressure will be in charge over the next couple of days so apart from early morning fog a couple of quiet days with sunny intervals. The exception being the far north where it will be cloudy with some patchy rain today and tonight But make the most of these two days

The forecast North Atlantic 300mb wind field and surface analysis for midnight Friday indicating rapid cyclogenisis is underway in mid Atlantic

gfs-deterministic-natl_wide-z300_speed-1033600.thumb.png.3bafdaf2977289c83b70b70a241ca95a.pngPPVJ89.thumb.gif.c1ece784329f7368ac24aba05f6c4fed.gif

Fronts associated with this track east through Friday and Saturday bringing rain and strengthening winds, clearing east by the afternoon And as can be seen the low is now a remarkable 928mb just east of the tip of Greenland

gfs-deterministic-natl_wide-z300_speed-1163200.thumb.png.f4e9c4fed0a3ae9322632712a218e283.pngPPVK89.thumb.gif.981202a59f5c1bfa7bad522b1f98f1fe.gifPPVM89.thumb.gif.9126644f7f1699571902c0996a4f0cca.gif

gfs-deterministic-uk-precip_6hr_inch-1109200.thumb.png.95c891c22723cbcdc210198b6373a85c.pnggfs-deterministic-uk-precip_6hr_inch-1130800.thumb.png.d6c17bad5d6e09cc21014a38e21f09fb.pnggfs-deterministic-uk-precip_6hr_inch-1152400.thumb.png.94e770e0b1a441a0e565d3cb9192c46d.png

gfs-deterministic-uk-t2m_c_max6-1098400.thumb.png.e549ba3b67ac113756741dc76dee82b5.pnggfs-deterministic-uk-t2m_c_max6-1184800.thumb.png.ea5859f77262675929c219968bd82211.png

But note other frontal systems are readily developing in the baroclinic zone south of the main trough and one of these tracks rapidly north east over Saturday night and through Sunday and this will bring heavy rain, squally heavy showers and gales, plus a marked temp contrast

gfs-deterministic-natl_wide-z300_speed-1249600.thumb.png.3c1e190ecb64f419b62a534a99679aaf.pnggfs-deterministic-natl_wide-t850_anom_stream-1249600.thumb.png.7a22ba81933c62961c58e2b7f1f1d9a9.pngPPVO89.thumb.gif.cf482116dc40c3b579e063c682ab38fc.gif

gfs-deterministic-uk-gust_kt-1238800.thumb.png.91b851a8a8df34f4e3be029caf3d1931.pnggfs-deterministic-uk-gust_kt-1249600.thumb.png.b20ea6c9931c462265451617285d7114.pnggfs-deterministic-uk-gust_kt-1260400.thumb.png.70664e9c3d75bbcff9d5ecb5be443507.pnggfs-deterministic-uk-gust_kt-1282000.thumb.png.ca2219ae7a6be60ecc410d7888db239b.pnggfs-deterministic-uk-t2m_c_max6-1271200.thumb.png.3477128da53e813a1ed086cec51ff285.png

 

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

There are always going to be differences between the models and Exeter regarding rapid developments within the intense pattern likely at the beginning of next week so I will just leave this with the gfs take on Monday/Tuesday. Very strong unstable north westerly portending squally heavy showers with just about everything in the mix on a much cooler couple of days. In fact feeling cold taking the wind into account

132.thumb.png.4495ecb71a451555c62f9136a597dc91.pnggfs-deterministic-uk-t2m_c_max6-1357600.thumb.png.6709043f68dd0fc9073aca1501bc01bd.png

156.thumb.png.4341dd252967c7cf0cd965219ca66b3d.pnggfs-deterministic-uk-t2m_c_max6-1444000.thumb.png.b7dd73e493150208022e61fabc64ff79.png

 

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Posted
  • Location: Camborne
  • Location: Camborne

To illustrate the point made above this is the ecm for 1800 Saturday

90.thumb.png.28b57353750a3f4d2549332ca0f94435.pngecmwf-deterministic-uk-gust_kt-1184800.thumb.png.24bd3f63aee6c072b5be7cbc01d2b932.png

And Sunday. The center of the low is nearly 10mb lower than Exeter

102.thumb.png.31db0d75f5cefc2f222a72133e49d2ee.png114.thumb.png.9a14848cea0a8b3317ec1c83cac3b55a.png120.thumb.png.75c1e1919b2d5c4d169ce9af60791ba2.png

ecmwf-deterministic-uk-gust_kt-1238800.thumb.png.bd92c3e683e48e87e73d96076683bf7a.pngecmwf-deterministic-uk-gust_kt-1249600.thumb.png.16c813d6cd53c8c5cc44f1c15433a102.pngecmwf-deterministic-uk-gust_kt-1260400.thumb.png.1d5b0afa66e9138fec4608a43441919e.pngecmwf-deterministic-uk-gust_kt-1271200.thumb.png.66482021d66297bb9a53eeaae5958954.png

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

Indications with this morning's ext mean anomalies of a resurgence of the NH subtropical zones along with a realignment of the tpv to be centred northern Canada extending south east into the NW Atlantic. By no means complete agreement on the detail with the GEFs tending to be the odd one out. Thus the percentage play is a continuation of unsettled weather but perhaps indications of a more benign outlook

ecmwf-ensemble-avg-nhemi-z500_anom_5day-2070400.thumb.png.ec71c8a1e4c11c06fc91b1574bcc3ae7.pnggfs-ensemble-all-avg-nhemi-z500_anom_5day-2070400.thumb.png.c5bc81dec5304a6613c45057ffde5ed9.png814day_03.thumb.gif.61dc063820869bbef60fd7a9b1cc06bd.gifecmwf-ensemble-avg-eur-t2m_c_anom_5day-2070400.thumb.png.ba4971cd573e189cf145c5f81d52fa98.pngecmwf-ensemble-avg-eur-precip_168hr_inch-2070400.thumb.png.da0cbb0db3bdd22fdd209e3df505831b.png

 

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Posted
  • Location: Camborne
  • Location: Camborne

This the is gfs take this evening. I'm not concerned on looking at specific wind speeds at the moment because forecasting accurately the intensity and track of this rapid cyclogenisis is tricky even at this range so adjustments are likely in the next day or two. Suffice it to say at the moment it's going to be very windy

gfs-deterministic-natl_wide-z300_speed-1228000.thumb.png.6764df283fde359a577a0d9dba91bacc.png78.thumb.png.7c77882ecd1e900bbd7ae6a2c63acb89.png84.thumb.png.d6f6638b644b15fa64dc958a55a0530c.png96.thumb.png.9cf3cf62a8df5ba81a5b0fe4bddeac85.png102.thumb.png.1f8fd4d4142b47b24910b6702c47c573.png

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

Outlook - very windy over the weekend

The North Atlantic 500mb and surface analysis for midnight

gfs-deterministic-natl_wide-z500_anom-0947200.thumb.png.7b0c1cae9476c8ef0451591b25af13b3.pngPPVA89.thumb.gif.59df7a52cea3865d7299e180119c391b.gif

After some early morning frost and fog today will be cloudy with sunny intervals

Quite a clear night to follow but winds starting to increase as pressure is exerted from the west

gfs-deterministic-natl_wide-z300_speed-1033600.thumb.png.833a17a563a5cd45c81c41aa1fe028a3.pngPPVG89.thumb.gif.dc20792b97c87abdd8d68b1b6326e04a.gif

Friday will start with patchy frost and fog and once cleared many areas will stay relatively sunny but cloud will encroach from the west, courtesy of the frontal system, during the day and patchy rain will arrive around 1500 in western areas. And by now the wind is really starting to pick up

PPVI89.thumb.gif.4e525b411bcc0080a45c9b1c00a72cb9.gif2mtemp_d02_45.thumb.png.437e485a7f917f1b35c1efd9eb7b0a8b.pngprecip_d02_48.thumb.png.17139ff7afe79b004eb0e07dc8e98349.png

Over Friday night and through Saturday the first frontal system sweeps through and the next quickly arrives on the scene and away to west around Newfoundland Ciara has appeared on the radar. So initially a band of rain then showers then more persistent rain, all accompanied by very strong winds

gfs-deterministic-natl_wide-z300_speed-1174000.thumb.png.1d109848cb78d9d318134341757af6b9.pngPPVJ89.thumb.gif.765e679cd2bcdb76bb8f451988c48177.gifPPVK89.thumb.gif.7031c0ffa6a982b298155181deafd9fa.gif

gfs-deterministic-uk-precip_6hr_inch-1141600.thumb.png.7db5add4d22776ffb220ddd2234525fa.pnggfs-deterministic-uk-precip_6hr_inch-1206400.thumb.png.2becbd5e356279e56ee6027a98fe9aca.pnggfs-deterministic-uk-t2m_c_max6-1184800.thumb.png.f6b11c3033e86368e135f69e7a438308.png

By midday Sunday Ciara has arrived and is 951mb over the Hebrides so a wet and very windy day with severe gales and much colder air behind the cold front

gfs-deterministic-natl_wide-z300_speed-1249600.thumb.png.fc040c498c0420ef44a27b62ecad106b.pngPPVM89.thumb.gif.2040e3b6f6a89201aad66816006ec5dd.gif

gfs-deterministic-uk-precip_6hr_inch-1271200.thumb.png.566b03edd4ae01a36728b14afcd16676.pnggfs-deterministic-uk-t2m_c_max6-1271200.thumb.png.30b6f12102a20074f11a35a951898368.png

By Monday Ciara is away over Norway leaving the UK in a very strong, unstable, and cold W/NW airstream with frequent squally heavy showers/ particularly in north western areas which could well be of snow and hail And the showers could well coalesce courtesy of troughs embedded in the flow

PPVO89.thumb.gif.5af34f5f0b8868279d66ec2945ca7b34.gifgfs-deterministic-uk-snow_6hr-1357600.thumb.png.99ff31b9825311dfa919a26e1b719663.pnggfs-deterministic-uk-t2m_c_max6-1357600.thumb.png.f8e5dae46ea7260d7387b833f479ddf0.png

 

 

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Posted
  • Location: Camborne
  • Location: Camborne

Little change on Tuesday and needless to say feeling very cold in the strong wind

132.thumb.png.7f09317d146d8eac10782933653de404.pnggfs-deterministic-uk-t2m_c_max6-1444000.thumb.png.17e351b21df78701c4b6c42cba5df5c1.png

And then remaining unsettled as the next frontal system arrives by Thursday, according to the gfs

168.thumb.png.c666f152c0201dd765af172df066fcf9.pnggfs-deterministic-natl_wide-z300_speed-1552000.thumb.png.89c1347794183bd71891e25283e24634.pnggfs-deterministic-uk-t2m_c_max6-1444000.thumb.png.76646e26b2ea10fbb44ba4b51ddbab45.png

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

According to the ecm unsettled for the first half of next week with some wintry weather and strong winds

ecmwf-deterministic-natl_wide-z300_speed-1465600.thumb.png.81c41f63f6309963c1d7a3db110a9447.png144.thumb.png.c13d156e9cee763c3ffed85d1e8650de.png168.thumb.png.1f44b8176b6e07c0699261dc613a2600.png

before further tpv developments in the west result in further amplification. Best left here

ecmwf-deterministic-nhemi-z500_anom-1638400.thumb.png.8c713234c94f8a3731a0782628f701ab.png

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Posted
  • Location: Camborne
  • Location: Camborne

The ext mean anomalies this morning are all on the same page without complete agreement. The main difference concerns the orientation of the tpv,, now centred over northern Canada, and associated trough into the Atlantic.and thus the amount of influence from the subtropical high in the east

ecmwf-ensemble-avg-nhemi-z500_anom_5day-2156800.thumb.png.2bb18870f71764926f8c17920946027e.pnggfs-ensemble-all-avg-nhemi-z500_anom_5day-2156800.thumb.png.e03bd4c76f570702139099c337b16ef6.png814day_03.thumb.gif.e8a94d00bed1fb763dea70e0b13561a5.gifecmwf-ensemble-avg-eur-t2m_c_anom_5day-2156800.thumb.png.4b5c92512f69d94869d8e33cfd402754.png

 

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Posted
  • Location: Camborne
  • Location: Camborne

The North Atlantic 500mb and surface analysis for midnight

gfs-deterministic-natl_wide-z500_anom-1033600.thumb.png.518c47d8eee44ffc9eebf0345af98121.pngPPVA89.thumb.gif.07e95a9fda6d4a30dd85537954753da9.gif

After early morning fog clears eastern regions will have another dry and partially sunny day but fronts are slowly tracking in from the west and cloud and patchy rain will encroach western areas from around through this morning and spread east during the afternoon accompanied by freshening winds

PPVE89.thumb.gif.337af1f03c0b61d136edfb2e5f28ef71.gifprecip_d02_24.thumb.png.ff0f175090410e42a4d946b9a7a054c1.png2mtemp_d02_21.thumb.png.6514625876f8acc730bd17677b8a9d61.png

The rain will continue east through this evening and overnight and become heavier, particularly in the north, courtesy of the second cold front, before clearing in the early hours of Saturday

PPVG89.thumb.gif.7ebf64a2f541a1e30a6687d0e77e48fa.gifprecip_d02_29.thumb.png.6d77223fae343aba643fde2377ca145f.pngprecip_d02_34.thumb.png.b400d1dcaf4357b40a7a4ad81b3bb750.png

Saturday will be windy with frequent heavy showers in western regions before a developing frontal system will bring heavy rain to the north west by late afternoon with winds increasing to gale, perhaps severe, force  And now storm Ciara has entered the scene stage left

PPVI89.thumb.gif.c9e4d6930caf233422db08d43900281c.gifprecip_d02_46.thumb.png.6687398adf693e1f0169b0c9855b1e9c.png2mtemp_d02_45.thumb.png.88406bddd60dea4ca294d1cfd4e5c83a.png

Over Saturday night and Sunday morning Ciara tacks rapidy east and deepens to be in the vicinity of northern Scotland 950mb by midday, Thus a day of heavy rain as the associated fronts track south east down the country with country wide strong winds reaching severe gale force in many areas

gfs-deterministic-natl_wide-z300_speed-1249600.thumb.png.f3f97d25245eb2892fa5d4660989baa1.pngPPVJ89.thumb.gif.992432831dc171133d4991ca062f6f4b.gifPPVK89.thumb.gif.312d08b132d13810a2c85cac8160f03e.gif

gfs-deterministic-uk-precip_6hr_inch-1271200.thumb.png.97f7458232459cf60d3da91611b58caf.pnggfs-deterministic-uk-t2m_c_max6-1271200.thumb.png.1e57b9c7e57c3e1bedcab02fd41a6479.png

By Monday Ciara is well clear to the north east leaving the UK in a much cooler and unstable airstream with gales persisting, particularly in the north. Thus the potential for frequent heavy and squally showers, particularly in the NW and these could well have hail and snow in the mix A glance at a forecast sounding indicates Cbs possibly  up to around 20, 000 ft. There is also a chance of more persistent rain as a frontal system nips through

PPVM89.thumb.gif.e31ad3aa881c93b167a2a8109b50b9c6.gifgfs-deterministic-uk-t2m_c_max6-1357600.thumb.png.3ed03ef0c553d0268d7cd482655ec1a6.pngsounding.thumb.png.fd74c771b38cfb7b4b4b7760b5baef1d.png

A not dissimilar day on Tuesday

PPVO89.thumb.gif.eb95e15dec4ebb0ca96389a871d47e9d.gifgfs-deterministic-uk-t2m_c_max6-1444000.thumb.png.a73b399e21e26b9d7043705d1144fc73.png

 

Edited by knocker
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5 hours ago, knocker said:

By Monday Ciara is well clear to the north east leaving the UK in a much cooler and unstable airstream with gales persisting, particularly in the north. Thus the potential for frequent heavy and squally showers, particularly in the NW and these could well have hail and snow in the mix A glance at a forecast sounding indicates Cbs possibly  up to around 20, 000 ft. There is also a chance of more persistent rain as a frontal system nips through

PPVM89.thumb.gif.e31ad3aa881c93b167a2a8109b50b9c6.gifgfs-deterministic-uk-t2m_c_max6-1357600.thumb.png.3ed03ef0c553d0268d7cd482655ec1a6.pngsounding.thumb.png.fd74c771b38cfb7b4b4b7760b5baef1d.png

A not dissimilar day on Tuesday

PPVO89.thumb.gif.eb95e15dec4ebb0ca96389a871d47e9d.gifgfs-deterministic-uk-t2m_c_max6-1444000.thumb.png.a73b399e21e26b9d7043705d1144fc73.png

 

Areas of low pressure form in the lee of the southern Greenland topography with a Greenland tip jet focusing winds and associated baroclinc zone. A low level feature, here are the winds at 850 mb at midday Monday -

850.thumb.png.55ad66bb735be5185f54fbed2c8dd437.png

The tip jet missing at 500 mb with the wind reflecting the broader upper level jet structure -

500.thumb.png.6d81e1bc36699e88196c6abfcfc605ee.png

The 500 - 850 mb wind shear showing stronger winds closer to surface in tip jet -

500-850.thumb.png.4fb998e50b99dbdea2339eb617cebe0d.png

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