Severe Storm January 2nd/3rd 2012 (Malin records gust to 169km/hr)

whataboutnow

Met office have significantly upgraded the storm in their forecast for n.Ireland warning of severe gales to storm force winds.exceptionally rare for them to mention storm force http://www.metoffice.gov.uk/weather/uk/ni/ni_forecast_weather.html

maquiladora

whataboutnow wrote: »

Met office have significantly upgraded the storm in their forecast for n.Ireland warning of severe gales to storm force winds.exceptionally rare for them to mention storm force http://www.metoffice.gov.uk/weather/uk/ni/ni_forecast_weather.html

The latest output from their NAE model that I posted above is probably the reason behind that. Look at the 960mb and tight isobars just above NI.

whataboutnow

maquiladora wrote: »

The latest output from their NAE model that I posted above is probably the reason behind that. Look at the 960mb and tight isobars just above NI.

True,could turn out to be quite severe indeed.given the current set up i wouldn't rule out 85mph where i'm at.Donegal 20miles from the coast

mickger844posts

Maq, Its looking like us in the South East might get something of interest for a change. The last half decent storm we got was in Nov 2010.

mountainy man

I think that if this plays out as you guys think ,I recon a lot of people will be caught out as we have got a bit complacent about recent storms. met eireann better pull the finger out in the morning and give a proper warning.

maquiladora

mickger844posts wrote: »

Maq, Its looking like us in the South East might get something of interest for a change. The last half decent storm we got was in Nov 2010.

All depends on the exact track and intensity. Bit of a nowcast. 70-80mph gusts possible on southeast coasts I'd say, but could be less.

M.T. Cranium

The GFS looked a bit slow to develop the storm, although they still get it to hurricane force off Norway and Denmark. All guidance so far takes the centre into Donegal Bay but around 100 miles south of that "route one" track we have grown accustomed to seeing. Realizing that Donegal has been on the edge of some extremely strong winds recorded out to sea in those storms, the track shift alone is of concern, then I have to underscore the high forward speed which is close to the maximum wind gust intensity being predicted in my alert. I have to comment at this stage (but will leave it out of the forecast) that such a set-up could explode into something very dramatic because normally you expect maximum sustained winds to be close to forward speed and gusts to be 1.4 times sustained winds.

Now sometimes when you get weaker features moving along at tremendous speeds, they lift off the surface and generate much weaker surface winds, but this case has such a classic looking low already that I really doubt that's the outcome here (possibly this was how it looked in the 5-6 day outlooks).

The storm has to move 40 deg of longitude in 24 hours as well as rising 5-6 deg of latitude. That's a forward speed between 80 and 100 knots. :eek:

Harps

UKMO almost identical to the GFS, just a touch further east but also going for a 965mb centre

whataboutnow

Harps wrote: »

UKMO almost identical to the GFS, just a touch further east but also going for a 965mb centre

what gusts do u reckon will be had in the twin towns harps?

maquiladora

Tryin to stay awake for the hi-res HIRLAM then hittin da sack! :pac:

whataboutnow

maquiladora wrote: »

Tryin to stay awake for the hi-res HIRLAM then hittin da sack! :pac:

we're mad ha

Harps

I'm still on my holidays for another 3 days so can afford the luxury of getting up at noon tomorrow Time for bed now anyway I think

whataboutnow wrote: »

what gusts do u reckon will be had in the twin towns harps?

Still a surprising amount of uncertainty about it and it depends on the exact track, I'm no expert but if it tracks right over Donegal then we'll escape without anything too severe but if its further north then we're right in the firing line.

0z HIRLAM going for something a lot more severe than the GFS or UKMO, a full 10mb deeper

amacachi

maquiladora wrote: »

That image is causing a login popup.

Edit your post, our quoting of the now-deleted post is causing the login popup :pac:

maquiladora

amacachi wrote: »

Edit your post, our quoting of the now-deleted post is causing the login popup :pac:

Haha, brain fail at 5:20am. Thanks.

mickger844posts

maquiladora wrote: »

Tryin to stay awake for the hi-res HIRLAM then hittin da sack! :pac:

Whats your source for the Hi res hirlam. Cant seem to find that in the usual places.

Redsunset

Sorry bout that,

Here it is


credited to "NERC Satellite Receiving Station, Dundee University, Scotland"

maquiladora

mickger844posts wrote: »

Whats your source for the Hi res hirlam. Cant seem to find that in the usual places.

http://www.lightningwizard.com/maps/

Very tightly packed isobars north of Donegal there.

mickger844posts

maquiladora wrote: »

http://www.lightningwizard.com/maps/

Thanks Maq for the link, Bit of a downgrade for the South on Hirlam?

M.T. Cranium

That would be the case (downgrade for south), but the Hirlam seems to be trading intensity for latitude compared to other guidance (more intense, further north). All options appear open at this point. It is very revealing to check the pressures on historical maps, none of the big storms that did wind damage since the 1903 storm have central pressures much below 970 mbs when approaching nor below 955 mbs in Scotland. The Dec 1886 storm of course had much lower pressures, as did the "Big Wind" of 1839.

Going back into the lab to check the ECM. However, I tend to trust the GEM regional on this sort of fast-moving event, the grid and initialization are probably better in this case. Have also noted a sharp increase in wind speeds in the southwest quadrant of the current low, first reports of gusts above 50kt now and well away from the centre near 1000 mbs.

Redsunset

02 January 2012 05:10 Met Eireann
A spell of more persistent rain will spread from the Atlantic this evening and early tonight, turning heavy for a time. It will become extremely windy or stormy, with very strong southerly winds early tonight, increasing strong to gale force southwesterly overnight, with gusts of 100 to 130 km/h or more, especially in western and northwestern coastal areas. Rain will give way to scattered showers later. Temperatures will rise overnight, but it will turn cold again as the rain clears. Minimum temperatures 2 to 4 Celsius,

M.T. Cranium

ECM looks more intense than either GFS or UKMO, and is very similar to GEM and NAE (is this also known as NMM or are they different?) ... I'm going to stick with my rather aggressive forecast in the interests of providing a warning, 5-10 knots will not matter much in the range of 70-90 anyway ... this is almost locked into being a major event now.

Redsunset

Issued at 02 January 2012 - 07:00
Weather Warning - Stormy Conditions
Stormy conditions developing Monday night into Tuesday, with gale force southwesterly winds and damaging gusts of between 100 and 140 km/h, strongest in Connacht and Ulster.

valid from 00:00hrs Tuesday 3 Jan
valid to 12:00hrs Tuesday 3 Jan

snaps

whats the time frame for this storm? Is it a gradual step up wind event from say mon afternoon until tuesday late morning, or is it bang straight into strong winds in the middle of monday night, then gone again by tuesday morning?

Deep Easterly

Surface Analysis for north Atlantic at 06z this morning:



The low center is approximately 4.0 mb higher, and a little further south by about 30 miles, going solely by a rough guess, than was forecast by Exeter yesterday (00z run, 24hr forecast fax chart attached at the bottom of this post), but overall, well called so far.

maquiladora

06Z GFS and NMM dont make this out to be severe. Max gusts of about 75mph on exposed coasts on those models.

On the other hand, we are under an Estofex Level 1 for "severe wind gusts".

... Ireland ...

A rather marginal situation in terms of deep convection will exist along the cold front of the compact Atlantic system reaching the western British Isles late in the period. Although no deep instability is advertised by either GFS or HIRLAM, strong mesoscale forcing for ascent along the cold front may support a narrow/shallow line of forced convection. Given wind velocities of 35 m/s at 850 hPa, the outflow of this convection may be accompanied by severe wind gusts.
The updrafts of this convection may be too weak and shallow to produce an appreciable amount of lightning.

Deep Easterly

snaps wrote: »

whats the time frame for this storm? Is it a gradual step up wind event from say mon afternoon until tuesday late morning, or is it bang straight into strong winds in the middle of monday night, then gone again by tuesday morning?

Winds should start increasing by around 9pm this evening in the SW and in most places by midnight or shortly after. Peak of the wind speeds are forecast to occur between 3am through to around 7am west to east. Tomorrow will be a windy day with the small chance of stronger winds during the afternoon.

Stay updated http://www.boards.ie/vbulletin/showthread.php?p=76270153#post76270153

maquiladora

gbee

Su Campu wrote: »

They are wind barbs. Each full barb is worth 10 knots

Just to advise new readers, these barbs follow the same criteria when the measuring scale is in miles or kilometres. For simplicity a triangle wind barbs is 50 in the measuring scale.

I mention this because some tombs on weather insist that the barbs are Knots only ~ if you have weather software on your smart phone one can change the measuring and watch the barbs change too.

maquiladora

Issued at 0600 Monday 02 January 2012


Gale warning: in operation

Small craft warning: In operation

Meteorological situation at 0500: A strong and unstable southwesterly airflow will persist over Ireland today. A storm depression will approach from the southwest early tonight, tracking close to northwest coasts overnight, generating an extremely strong southwesterly airflow over the country.

Forecast for Irish coastal waters from Fair Head to Howth Head to Carnsore Point and for the Irish Sea
Wind: Southwesterly, force 6 or 7 and gusty, increasing southerly, force 7 to strong gale force 9 by midnight, further increasing southwesterly, gale force 8 to storm force 10 overnight.

Forecast for Irish coastal waters from Carnsore Point to Mizen Head to Slyne Head
Wind: Southwest to west, force 6 or 7 and gusty, increasing southwest to south, force 7 to gale force 8 this evening, further increasing southwesterly, gale force 8 to storm force 10 tonight, later decreasing west to northwest fore 7 to strong gale force 9.

Forecast for Irish coastal waters from Slyne Head to Rossan Point to Fair Head
Wind: Southwesterly, force 6 or 7 and gusty, occasionally gale force 8 today, increasing southerly, force 7 to strong gale force 9 later this evening and early tonight, further increasing southwesterly, strong gale force 9 to storm force 10 tonight and possibly reaching violent storm force 11 in the northwest and north.

http://www.met.ie/forecasts/sea-area.asp

gbee

My weather barbs in this app are set to km/h