FI CHARTS AUTUMN/WINTER 2014/15 **Mod Note Post #1**

maquiladora

06Z GFS a little bit more interesting, a pair of lows bringing very strong winds to northern Scotland and at times some strong winds to the northwest/north coasts here. Not as southerly or as powerful as the storms that have been cherrypicked from GEFS runs, but one of the more interesting op runs.

First low :




Second low the next day :


The first low would actually meet the criteria for a red warning from Met Eireann for northwest coastal areas here, despite the low not really looking that significant for us, which should give some indication how severe those ensemble storms that do look significant for here would be.

06Z GFSP keeps things much further north with nothing interesting for here really. It's all very FI at the moment.

ninebeanrows

Some corkers on the GFS ensembles.

Just focusing on storm 1. Storm 2 could be worse.

ninebeanrows

Highest sustained for coastal Dublin I can see is around 100kph




But just off shore one heads towards sustained 120kph.





God knows what they are like off the north coast!

maquiladora

Weathercheck wrote: »

Some corkers on the GFS ensembles.

Just focusing on storm 1. Storm 2 could be worse.

I think it helps sometimes to get some kind of perspective when looking at these ensemble storms to compare with these charts from the storm of Feb 12th 2014 which produced :



This GFS chart that morning :



And compare that to Ensemble 1 :

ninebeanrows

12z GFS OP not developing much, the second low just can't phase correctly.

First low brought into Scotland with storm winds, but nothing exceptional.

Does create a mini-cane for the Faroes though

maquiladora

Little change on the 12Z GFS with the first low, about the same intensity as the 06Z, just a tad further north. Second low is different and stays further north.

Gusts :



Sustained winds exceptionally strong as it approaches northwest Scotland. The little black area showing mean winds of 150+ km/h, borderline strength of a low end Cat 2 hurricane in that area. Sustained :



The 12Z GFSP develops a strong low but well north of Scotland so not much interest to anyone. 12Z UKMO doesn't seem too interesting either.

Iancar29

Theres also this bad boy that both GFS and GFS (P)throw up with the GFS P having it a bit stronger...


Red Warning criteria for all counties apart from Ulster on this track.



Then cold air feeding down behind bring a snow risk to the N and NW

maquiladora

Iancar29 wrote: »

Theres also this bad boy that both GFS and GFS throw up with the GFS having it a bit stronger...

It's an Iancar special alright.

Iancar29

maquiladora wrote: »

It's an Iancar special alright.

maquiladora

ECM says "nope", and it's probably right. It was last time.

ninebeanrows

ECMWF not developing anything too interesting on its operational again

... Lots of stormy ensembles on the 0z but interesting nonetheless, possibly we will get away with just a windy day

ninebeanrows

Looking at the progression from 96 to 120hrs on the EC just doesn't look right to me, a deepening of 10mbars? I don't think so.

maquiladora

Weathercheck wrote: »

Looking at the progression from 96 to 120hrs on the EC just doesn't look right to me, a deepening of 10mbars? I don't think so.

I think it's down to the timing and positioning difference between the GFS and ECM by 96 hours. GFS must just have the low in a more favorable position to develop along the jet.

Iancar29

GEFS Perturbation 3 wins the cherry picking 12z sesssion!
Storm 1 for the northern half of the country 12th Jan. :cool:


48hrs later this bombing low eyes up the southern half of the country. Blizzards for England Wales and the Wicklow mountains if this came to fruition! Similar to 22nd Jan 2013.





Probability of it happening? .... about 5% but sure its still exciting!

RED L4 0TH

Iancar29 wrote: »

48hrs later this bombing low eyes up the southern half of the country. Blizzards for England Wales and the Wicklow mountains if this came to fruition! Similar to 22nd Jan 2013.


Probability of it happening? .... about 5% but sure its still exciting!

Wouldn't you need a longer track for the northeasterlies to pull in colder air? The corresponding 850 hpa chart isn't great.

Iancar29

RED L4 0TH wrote: »

Wouldn't you need a longer track for the northeasterlies to pull in colder air? The corresponding 850 hpa chart isn't great.

Not necessarily no. Due to the low central pressure , the 850hp level would be lower down in the atmosphere resulting in less time for any precip to be warmed up while falling. So -4 or so would do it , especially at high ground .

maquiladora

18Z GFS much weaker with that low than previous runs. No surprise really to see it starting to look more like the ECM.

The difference is huge!

AnotherYear

Further south on this run too. GFS P shows nothing. Shame, was hoping for something interesting

Oneiric 3

The speed in which tonight's ECM has a cold front moving through either later Friday on early Saturday is pretty interesting in itself. Although not associated with a particularly tight or steep pressure gradient as it crosses, it may still have the potential to bring some (very?) squally winds for a time - assuming of course, that subsequent outputs keep this feature as it more or less as it is - which it probably won't.

Nabber

yes....

ninebeanrows

Can we lock this thread!?

Anything exciting we post up never happens!

Models moving away from anything severe with the strongest winds likely to be north of Scotland.

Still a little uncertainty with regards to Friday morning's system, which still has potential to cause some disruption.

maquiladora

Yep, downgrades from the 18Z onwards yesterday. But the ECM is seldom wrong within this timeframe with these kind of events, so not too surprising really!

Back to the drawing board in the hunt for interesting FI charts...

Darwin

The Azores high has been our nemesis in the hunt for cold, but at least on this occasion it is doing us a favour in keeping the worst of those storms out of the way. It does look like getting flattened by T+192 on the ECM with some very cold air to follow.

howlinwolf

Weathercheck wrote: »

Can we lock this thread!?

Anything exciting we post up never happens!

Models moving away from anything severe with the strongest winds likely to be north of Scotland.

Still a little uncertainty with regards to Friday morning's system, which still has potential to cause some disruption.

Yeah its seems like every interesting model trend is blown away when the timeframe gets into reliable territory ... The ecm does seem like the only model to put any faith in as it has been on the ball lately , the rest of the models might as well just put up pictures of nice big chocolate cakes :-) time will tell if the ecm is again spot on or even more interesting if the ecm goes the way of the other models and starts getting in on the storm trend ....hopefully a few interesting days ahead

Nabber

Can we not just post charts? Its calld fantasy island for a reason



What a monster. Iceland may be attached to Galway by the end of this.

icesnowfrost

still trying to bring in a nort to north east

Oneiric 3

Nothing exciting in the outlook for sure, but looking ECM 500 hPa pattern out to day 8, there seems to be tentative trend towards lowering heights to our NW, helping to tightening pressure gradient over our latitudes, which in turn may help to increase our chances of seeing some relatively active weather as we move into mid-Jan.

tiegan

Fantasy Island?? More like Fantasy Ireland!!

ninebeanrows

Both lows still quite volatile with their positioning but the Saturday morning Low still has a could deal of error in its track so one to watch, a few 6z ensembles take this further south.

12z is nasty for Scotland

ninebeanrows

UK is severe enough




---- The 108 chart would be interesting as it is likely the severe gradient would have past through some northern areas