This Week's Storms - FORECAST, MODEL DISCUSSION ONLY

nacho libre

the ukmo could be on to something indeed, that other models haven't picked up on.
i remember they were confidently predicting of the cold conditions we got in late November last year, before most of the other models picked up on it. So maybe this could be another example of that.

M.T. Cranium

The UKMO solution is really the only one that looks "right" as the outcome of what all models show at 48h on Wednesday 12z. That storm looks developed enough to push in against the jet and interact with it, rather than getting sheared off as per the other models.

This storm 2 debate is however having the effect of shifting attention away from what is developing towards a severe windstorm in the northwest tomorrow. I feel that the max gusts will be considerably higher than previous storms and also higher than the official forecast of 130 km/hr (as I've said in my forecast).

I know the folks in the northwest are battle-hardened but this one could be a touch more than expected from what I'm reading on here anyway, so would say be prepared for more than just a normal windy day. All I can say at this point, but a 945 mb low dropping down towards Donegal Bay is about as intense a storm as we see outside of the once-a-century type. And when you factor in how cold the circulation is ... well, it's that sting in the tail business that I mentioned last week.

If I had to stake my life on it, I would say south coast is at risk of strong winds on Thursday night. But by the conventional methods of model consensus, the chances are about one in three. It's like those odds you sometimes see that don't seem right and perhaps this is one where Basel wins and Man U loses (wrong analogy by model names, but anyway, I couldn't find a more appropriate one). :eek:

gbee

Deep Easterly wrote: »

Links to FAX forecast charts (in Tiff format)
(24hr) )

Can one be downloaded without buying an Apple Product?

Deep Easterly

gbee wrote: »

Can one be downloaded without buying an Apple Product?

I don't have an Apple just an ordinary Windows laptop and those charts usually open automatically in Microsoft's Picture Viewer. If you don't have that you could assign them to open in Photoshop or similar program.

This link shows the latest FAX charts as well in a less complicated format:

http://www.zeilen.nl/meteo/bracknel.htm

Harps

Available on meteociel as well..

http://www.meteociel.fr/modeles/ukmo2.php?carte=2000&ech=0

Rougies

Harps wrote: »

Available on meteociel as well..

http://www.meteociel.fr/modeles/ukmo2.php?carte=2000&ech=0

And on Wetterzentrale (Bracknel are the UKMO ONES)
http://www.wetterzentrale.de/topkarten/fsfaxsem.html

maquiladora

Deep Easterly wrote: »

Very much in line with the UKMO model output. Will be interesting to see the ensemble mean run from ECM when it eventually rolls out to see if there is any change in positioning.

http://meteociel.com/modeles/ecmwf.php?ech=72&mode=1&map=0&type=2

ninebeanrows

Only a handful of ECM EPS follow the UKM, i count 7/50

ninebeanrows

What i note from the EPS members at 24hrs, that a number show something worse than the op with the low further south and deeper.

Some very strong winds tomorrow and i will post my full thoughts after the 18z for tomorrow, there could be some extreme winds arriving tomorrow throughout the day. And quite out of the blue for many.

Harps

Link for the ensembles?

Tom Cruises Left Nut

Think this is it

http://www.ecmwf.int/samples/d/inspect/catalog/samplers/banner/mean_sea_level_pressure_and_temperature_at_850hpa!168!pop!od!enfo!enplot!2009112700!!/

JanuarySnowstor

What's your thoughts on the snow potential Matty??
850's look too high yet the beeb and Met Eireann mention snow!

My thinking is quite a bit of falling snow in heavier showers but nought sticking away from mountain tops

Deep Easterly

Weathercheck wrote: »

What i note from the EPS members at 24hrs, that a number show something worse than the op with the low further south and deeper.

Very similar between op and en mean run at 72 but at 96, op still a little further south:


Not that that means anything really but gives an idea to the extent of deviation this evening's deterministic run is showing from the ensemble mean.

nacho libre

the potential temperature still looks too high for sea level snow??

Su Campu

nacho libre wrote: »

the potential temperature still looks too high for sea level snow??

Yes. From those charts, the 500-1000 thickness would need to be at most 522 dam, more like 518, and the 850 theta-e around 10-12 °C or less for snow to sea level. Just too much sea track modification for proper snow, so I reckon wettish snow above 100-150 metres at the lowest.

Dewpoint around 0 but dry-bulb temperature of around 3-4 C will mean wet-bulb temperature around +2 °C, meaning snow can melt. That is why it's more important to watch wet-bulb than dewpoint.

ninebeanrows

You can see the very strong and deepening LP with its wrap around slowly pushing southwest.

Looks ominous and winding up further.

Expected to be nr 940mb by midday tomorrow just 100km off the north coast.

http://www.sat24.com/en/gb

irish1967

Don't know if this has been posted yet
Met office video

http://www.youtube.com/watch?v=KKocsW_uBXY&feature=youtube_gdata_player


On phone maybe someone could fix link.

ninebeanrows

I think the RTE forecast was done very well.

Gave enough warning without going into serious detail on windspeeds.

Stormy tomorrow, but to what extent, is still quite uncertain.

And blunt about the uncertainty for Thursday night!

Deep Easterly

NAE 18z run has winds really picking up tomorrow evening over the northern half of Ireland:



This model has the shortwave feature Su mentioned earlier passing innocuously to our SW Wednesday eve but the 18z HIRLAM (EMHI) has it optimistically a little further north:



Complex complexities.

JJJJNR

Any risk of freezing rain tomorrow morning lads?

Speak Now

JJJJNR wrote: »

Any risk of freezing rain tomorrow morning lads?

Shouldn't think so.

Deep Easterly

JJJJNR wrote: »

Any risk of freezing rain tomorrow morning lads?

Literally speaking, no; but if you mean cold rain, then yes with NW in general getting more in the way of rain than the SE (not sure what part of the country you are in).

Su Campu

JJJJNR wrote: »

Any risk of freezing rain tomorrow morning lads?

No chance except for the highest summits.

Pangea

Deep Easterly wrote: »

NAE 18z run has winds really picking up tomorrow evening over the northern half of Ireland:



.

Im in the brown there, what does 36 stand for?

maquiladora

Pangea wrote: »

Im in the brown there, what does 36 stand for?

About 40mph winds.

Deep Easterly

Pangea wrote: »

Im in the brown there, what does 36 stand for?

I must be colour blind because I see that as red but it indicates mean (sustained) windspeeds of 36kts + which is equal to BF Gale 8 or 67km/h, i.e, windy!

Harps

Says knots in the title, assume that's sustained wind, gusts will obviously be a lot more

ninebeanrows

Can't see GFS 18z going to UKM sol.

The Westerner

18Z GFS for 9.00am tomorrow.

Hooter23

Just saw bbc weather they showed Thursday he said they are "very confident about a deepening low pressure system with vicious winds" and it showed it crossing over ireland :eek: OMG