Storm Barra: December 7/8th 2021 **Technical Discussion Only**

octsol

It doesn't seem as bad as was expected here in North kerry. Its windy but nothing out of the usual.

Has it changed direction slightly

Gaoth Laidir

Met Éireann aviation chart for 12Z has the low at 959 hPa and centred right over the Aran Islands,

Waterford Airport TAF has just been amended. Max gusts 55 kt in the next couple of hours.

TAF AMD EIWF 070640Z 0706/0715 18028G42KT 9999 -RA BKN019 TEMPO 0706/0709 18035G55KT 4000 RA BKN009 TEMPO 0706/0708 1400 +RA PROB30 TEMPO 0712/0715 -SHRA SCT018CB=

Kerry max gusts 52 kt from 11 am.

KERRY TAF EIKY 070500Z 0706/0715 19025G42KT 9999 BKN020 TEMPO 0706/0707 7000 RA BECMG 0708/0710 23025G42KT TEMPO 0708/0715 SHRA SCT018CB BECMG 0711/0713 26034G52KT=

Gaoth Laidir

06Z analysis. 961 hPa.

These are the 6-hourly central pressures from 00Z Monday to 06Z today. A drop of 55 hPa in the past 24 hours.

1019 - 1016 - 1009 - 992 - 975 - 961

Gaoth Laidir

07Z. Sherkin Island gust 62 kts.

PsMETAR SHER 070700Z AUTO 21044G62KT 4100NDV -SHRA BKN025/// 09/05 0977 MSL=

Mace Head has the lowest pressure, 969 hPa.

DOCARCH

Sherkin reporting 44kts, gusting 62kts, at 0700.

That 44kts is a Red level sustained/mean wind speed.

Meteorite58

No great deviation in the overnight charts.

ICON , EURO4 at the upper end of the scale, ARPEGE and American models probably a good guidance at this stage.

pad199207

145kmh gust at Fastnet

Meteorite58

Activity off the W Coast this morning.

Meteorite58

Taking shape

Oneiric 3

WV image. Ireland now entering black hole territory.

Pressure 970.0hPa here and falling more slowly.

pad199207

Sustained 131kmh and gust 156kmh at Fastnet

Supercell

Dont recall such sustained winds in Dublin before, quite impressive :

TAF EIDW 070500Z 0706/0806 14020G35KT 9999 FEW012 BKN020

  TEMPO 0706/0709 15028G45KT

  BECMG 0709/0711 18025G40KT

  PROB40

  TEMPO 0709/0711 17035G50KT 6000 RA

  PROB40

  TEMPO 0713/0718 4500 SHRA BKN012 SCT018CB

  BECMG 0714/0716 20025G40KT -SHRA

  BECMG 0716/0718 24018G30KT

  BECMG 0721/0723 27025G45KT

  PROB40

  TEMPO 0800/0806 4000 SHRA BKN008 SCT018CB

DOCARCH

Recent gust of 67.2kts (F12) at DunLaoghaire Harbour. Can't remember seeing a gust that strong there before!

Donegal Ken

Donegal, Sligo and Leitrim are looking even more likely to be added to a orange warning on Wednesday morning now wirh strong winds and coastal flooding there possible as storm barra clears to the east/northeast. Snowfall also been reported to myself this morning across many parts of Donegal with very poor conditions and low visibility due to blizzard condition. Image attached is between Letterkenny to Barnesmore.

Laurali

What do you use to track arpege model? I am only used to looking on Ventusky and Windy and never see Arpege?

sorry for novice question

SouthWesterly

156 kmh recorded at fastnet

944 hPa here in North kerry

Supercell

Recorded a gust of 87 km/ph a short time ago, highest since January 2nd 2018. My anemometer is not official height and likely under recording, a fairly decent storm for around here.

For some context, Ophelia's maximum gust here was 83km/ph in 2017.

M.T. Cranium

Strongest winds likely to develop over Kerry by about 1030h lasting several hours, the southwest quadrant of the low has stronger winds than the southeast at present, so when those rotate around and hit the southwest you are likely to see locally damaging gusts to around 130-150 km/hr.

Have done a review of the current forecasts as part of my own preparations and would generally agree with most of what I read, although I would probably extend orange level alert to Tipps and Kilkenny (our readers in any case would know that exposed locations there would match conditions further west). Could be borderline red alert along Waterford and Wexford coasts too.

Will just underscore the "lull" feature one more time, for those likely to be close to the track of the low especially in Connacht and Ulster, expect an interval of reduced wind speeds, the duration depending on your distance from the storm track, and when the lull ends, a rapid increase with northwest to north becoming the prevailing direction then. A little further south of the track, for example in coastal Clare or east Galway, the lull will be more of a slight reduction in wind speeds that might appear to be a premature end of the storm, but will in fact not be that but just a temporary easing of the storm force gusts. There won't be any such phenomenon for most parts of Munster or Leinster except for those parts very close to Connacht.

pad199207

Remarkable pressure falls in 3 hours

Akrasia

https://www.boards.ie/discussion/comment/118282347#Comment_118282347

Wow, is this from a decent weather station? Thats deeper than modelled and this is 100km from the projected center of the storm?

SleetAndSnow

https://www.boards.ie/discussion/comment/118282419#Comment_118282419

Fastnet is a lighthouse on a rock off the coast of cork and Is up high. It's generally nothing of what the mainland will experience but tis always fun to see what numbers it reaches!

Track the speeds here https://twitter.com/FastnetLHouse?t=A68XxYQg5BU9rFgC6PSn0g&s=09

pad199207

Cold front clearing now

SouthWesterly

https://www.boards.ie/discussion/comment/118282419#Comment_118282419

It's a bresser

I'm at 160m asl

Meteorite58

https://twitter.com/BantryFire/status/1468111885685993472?s=20

https://twitter.com/countykerry/status/1468145374724513793?s=20

https://twitter.com/countykerry/status/1468145374724513793?s=20

https://twitter.com/RBurneika/status/1468142646778601472?s=20

https://twitter.com/RBurneika/status/1468142646778601472?s=20

https://twitter.com/Buailtin/status/1468149600766808067?s=20

Danno

Top gust of 45mph (72kmph) at standard 10m height here in southern Laois. Also 12.2mm. Rough for a time here around daybreak but a bit of a drop off in wind speeds once the cold front blew through. Temperatures peaked at 9.1c earlier, down to around 7c presently - so the cold air is marching back in. It was a short-lived mild sector! Pressure: 973hPa.

Winds...

Meteorite58

From Donegal earlier

https://twitter.com/GregHughes2/status/1468132775802949632?s=20

https://twitter.com/HarryWalsh65/status/1468144848893005826?s=20

Meteorite58

Will see how the thunderstorm threat pans out today, certainly will be very squally later .

Day 1 Convective Outlook

VALID 06:00 UTC Tue 07 Dec 2021 - 05:59 UTC Wed 08 Dec 2021

ISSUED 07:05 UTC Tue 07 Dec 2021

ISSUED BY: Dan

Around the southern flank of a deep cyclone, a significant cold pool will overspread relatively warm SSTs to generate several hundred J/kg CAPE in the post-frontal environment. Numerous showers will develop and move inland into Wales and SW England (and SW Ireland), and increasingly through the English Channel during the evening/night and into adjacent coasts. Sporadic lightning and hail will be possible, perhaps also extending further north up through the Irish Sea. Squally winds will accompany many of the showers, at least for a time given mixing down of higher momentum air within the low-level jet - and a SVR has been issued to highlight the area at greatest risk of convective gusts exceeding 60mph (on top of an already strong background wind field). Meanwhile, strong shear with wind veer and shallow convection along the rear of the occlusion could lead to some line convection/squally conditions during Tuesday daytime. 

mickger844posts

106km/h recorded at Waterford Airport in the last half hour. I'm expecting peak gusts here between now and 4pm with no major drop off until tomorrow morning.

https://waterfordcityweather.com/index.php

squarecircles

Dead silent and Flat calm in west Mayo.

SouthWesterly

Blue skies in North kerry