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

icesnowfrost

GFS - P seems to be last to get on board with proper cold flow but I think it will over the next few runs

Iancar29

maquiladora

Some interesting FI charts on the 06Z runs this morning.

gfs :



gfs p :

Villain

The difference in just one run shows you how uncertain FI currently is

oneGFsrun

maquiladora

More interesting stuff from the 12Z GFS and GFS P from the 27th onwards...

ninebeanrows

Yes, definitely a storm focus around 26-28th December, then a potential for a cold spell thereafter.

Could be an interesting post-Christmas

A pretty delightful 12z GFS OP for us coldies

Iancar29

Nice to see the initiating Low has been kept alive on recent runs.

516 dam line anyone? :cool:

maquiladora

12Z GFS and 12Z ECM mean at 192 are fairly similar.




The ECM operational at 192 looks questionable in comparison...



It's all FI though of course.

maquiladora

Another variation on the same theme on the 18Z GFS. A complex mix of heavy rain, snow and severe gales as a low deep crosses the UK on the 27th, further south than the 12Z. Strictly FI as this is a long way from being resolved.

GFS P is sadly out of action this weekend.

elecktras weather bomb

can someone tell me what time frame is F1 at the moment? thanks in advance .

maquiladora

elecktras weather bomb wrote: »

can someone tell me what time frame is F1 at the moment? thanks in advance .

It's not F1, it's FI : Fantasy Island.

Reasonably good confidence now up until around the 25th. The scatter sets in then quickly after that.

Harps

Definitely a much bigger cluster towards a colder setup after Christmas on that graph than the past few days, if you ignore those 3 runs keeping it mild then the mean is probably down to about -4 or -5C, very different to the ECMWF op. Naturally the mild runs can't be ignored though as long as the ECM is going that way.

Still looks about 50/50 whether we'll see any sort of significant storm around the 27th as well

elecktras weather bomb

oops @ maq all this festive cheer and headache from this model watching has gone to my head. extreme fatigue already and the next few days it will be impossible not to have a peek. cheers

maquiladora

Most of the 18Z GFES are a bit messy and not great though.

maquiladora

A potential major snowstorm for Scotland on the 06Z GFS.





Snow showers here too after it passes.



Still massive uncertainty with this of course.

Iancar29

I was looking at the normal GFS thinking the Parallel was still unavailable , it has the low going south instead and not pulling in enough cold air. This though keeps things interesting indeed .

Even though Scotland gets the blizzard potential , Ireland still gets its fair share for snow risk .



ECM still very messy this morning , it seems to want to initiate the low but just doesn't really get it going ..

maquiladora

Couple of interesting GEFS members...

Oneiric 3

On the BBC Weather Weekly Outlook around 5.30 this morn, the presenter hinted that a deep low could bring copious amounts of rain to southern UK after Christmas with snow potential in the north. She gave a high degree of uncertainty to this forecast though given wide range of possibilities on offer.

Looking as some of the solutions on the models, the east of both England & Scotland could potentially do well if that storm depression does develop as vigorously as the GFS had it yesterday (I haven't seen today's runs yet)

Personally, I'll take a good dump of snow if it is on offer, but I'll equally (if not more so ) take a good, ferocious storm or two in the weeks ahead, because the weather this December has offered so far has been nothing less than stupendously, soul-slaughteringly boring.

maquiladora

Oneiric 3 wrote: »

On the BBC Weather Weekly Outlook around 5.30 this morn, the presenter hinted that a deep low could bring copious amounts of rain to southern UK after Christmas with snow potential in the north. She gave a high degree of uncertainty to this forecast though given wide range of possibilities on offer.

Looking as some of the solutions on the models, the east of both England & Scotland could potentially do well if that storm depression does develop as vigorously as the GFS had it yesterday (I haven't seen today's runs yet)

Personally, I'll take a good dump of snow if it is on offer, but I'll equally (if not more so ) take a good, ferocious storm or two in the weeks ahead, because the weather this December has offered so far has been nothing less than stupendously, soul-slaughteringly boring.

A ferocious low with inland gales and torrential rain transitioning to heavy snow, building huge drifts....it's about as exciting as it gets. Chance of it actually happening here are slim knowing our luck, but at least the models are hinting at a possibility....

Scubadevils

On that note, Old Met Man's post on NW a short while ago is along those lines... any mention of '82 is always nice! I've no idea how to include the chart he posted in the below quote however...

The models' ambivalence as to what happens on or after Christmas Day continues. The spectacular looking LP for 27th would indeed be interesting, but I guess the chances of anything like it happening at this distance are pretty remote, although having said that, it is a possibility.

What I find odd still is that there have been no real signs within the models of a pressure build from the NW after Christmas. Pressure rises to the S or SW yes, but that is all. Several days of cold air coming S across the Norwegian Sea, LP much weaker over Scandinavia, a situation which has in the past given rise to some noteworthy frontal battle grounds between cold and mild.

Here's a nice example from 1982.

archivesnh-1982-1-6-0-0.png

That one produced significant snow across the S as an advancing frontal zone stalled as it pushed into the cold air to the N.

As always, I am aware that no 2 situations are ever the same, and I wouldn't mention it but for the indecisiveness of model output at that time, but it's an intriguing possibility and, dare I say it, no less unlikely than the GFS major storm!

It will be interesting to see later model output and whether we have any sort of consensus developing.

https://forum.netweather.tv/topic/82046-model-output-discussion-the-run-in-to-christmas/?p=3092754

Harps

I'll take a good northerly a la the GFS P, while the winds on offer don't look too noteworthy I always find northerlies have more bite to them than our usual westerly storms, add in the prospect of heavy blowing snow and thunder and it'd make for an interesting couple of days

Still any number of outcomes from the 26th onwards, unfortunately a lot more agreement this morning of the inevitable continuation of boring weather but still some interesting possibilities so all we can do is hope

rickdangerouss

Now the direction for any SSW is getting pushed back again, An +AO\NAO may be on the way for mid January onward, Matt has been updating chances of an SSW, Most of the following comments agree with this.

Is its this end of -OPI? Find out next week.....

Doesn't make for good reading if you ask me to be honest. Given the overal initial conditions that we started off with this winter, it would seem as though there have been and continue to be some major counter-balancing influences that, overall, are scuppering the developments really. The suggestion of a SSW in late January is definitely far later than most were thinking this winter and clearly a late January SSW may well lead to an interesting month in February but clearly we are then progressing towards late winter. Without question the majority, if not all of the forecasts issued (excluding the UKMO) were indicating a particularly -ve AO pattern through the mid and latter half of the winter and that includes Netweathers.

Clearly, like anything in meteorology nothing is set in stone and what surprises me about the latest discussion is the lack of emphasis on the warming and wave 1 activity that is developing now and the potential for a split, as per some models, by early January. The suggest that the AO and NAO may return to more neutral or perhaps even +ve states by mid-January is not a good thing to read to be honest.

As ever time will tell, but a poor update and an update that would signal a trend away from a potentially 'interesting' January in terms of cold synoptics.

Matt.

https://forum.netweather.tv/topic/81567-stratosphere-temperature-watch-20142015/page-41

maquiladora

Scubadevils wrote: »

On that note, Old Met Man's post on NW a short while ago is along those lines... any mention of '82 is always nice! I've no idea how to include the chart he posted in the below quote however...

This was the day of heavy snow here in 1982. Low pressure off the south coast, raw easterly winds, severe cold air to our east.

Its Only Ray Parlour

Scubadevils wrote: »

On that note, Old Met Man's post on NW a short while ago is along those lines... any mention of '82 is always nice! I've no idea how to include the chart he posted in the below quote however...

numilus cimbus

The 82 storm started late of a Wednesday night and carried on to Saturday morning
Drifts in parts of the East to the top of Esb poles and it was a thunder snow event too
Food parcels had to be dropped in the Dublin and wicklow mountains because the roads were buried
It only lasted a week though (although the drifts took a month to finally thaw),the rest of that winter was benign
There are threads here dedicated to it,I can't link

That was a true blizzard.
2010 had hardly any wind

Tom Cruises Left Nut

Heh

maquiladora

Liam Neesons Ballbag wrote: »

Heh

Yep...




Still very uncertain though. Old GFS handles things differently.

Kermit.de.frog

Boom

Oneiric 3

maquiladora wrote: »

A ferocious low with inland gales and torrential rain transitioning to heavy snow, building huge drifts....it's about as exciting as it gets.

Add in just a little bit of this...

https://www.youtube.com/watch?v=qJt4nV6hM1Y

And we have perfection!

Iancar29

I am happy with this evenings charts , both GFS ( P ) and ECM have the low active. The difference currently now is where it deepens rapidly .

The ECM deepens it to the the NW of the country , delaying the colder air tucked in behind it a bit . It still brings cold air down eventually as it moves east but not giving widespread cold enough air bar the top half of the country .


The GFS however , deepens the low to our NE and slightly deeper than the ECM bringing down cold air quite rapidly giving widespread snow risk .


Atm i think the solution for the development of the LOW in the GFS looks more realistic in terms of the way the low looks at maturity , compared to how ECM splits it up , quite messy looking. Any inbedded troughs will not be picked up too until at least Monday evening , were we should start taking it more seriously if charts continue on this pattern.

Until tomorrow , from me ...