Model Outlook Thread: January 2010

Gonzo

im not sure what to expect anymore, even if we get another cold beast from the east, doesnt mean people in Louth and Meath will see much snow, I did not realise till this time around that the Isle of Man could be such a snowkiller for Meath. We need easterly winds that form showers for us in line from below Isle of Man to North Wales.

ninebeanrows

Gonzo wrote: »

im not sure what to expect anymore, even if we get another cold beast from the east, doesnt mean people in Louth and Meath will see much snow, I did not realise till this time around that the Isle of Man could be such a snowkiller for Meath. We need easterly winds that form showers for us in line from below Isle of Man to North Wales.

It all depends on the exact flow!

you would win on a straight Easterly or ESE.

You just got unlucky.

Deep Easterly

ECMWF showing something a bit more interesting tonight:



Almost 1947 esque! :eek:

Weathercheck

Weathercheck wrote: »

It all depends on the exact flow!

you would win on a straight Easterly or ESE.

You just got unlucky.

Whereas I'd want a ENE or NE :pac:

I'm not liking the look of those charts general direction as I've to fly into and out of gatwick at the end of the month ...an airport that almost closes with frost these days

francosp

Mmmm, is this starting to look like a return to Easterly winds come the end of the month ?

Baby steps...
But yes.

maquiladora

06Z GFS 180hrs :

200motels

maquiladora wrote: »

06Z GFS 180hrs :

A long way off as you know, I don't want the cold to return.

nilhg

Even in the GFS there's not much ensemble support for another proper cold spell



Going to jump all over the place in the next few runs I'd imagine before any clear trend emerges.

Kippure

Model performance is expected to be poor over the next week or so.

Rougies

Kippure wrote: »

Model performance is expected to be poor over the next week or so.

Can I ask why?

The weather set up is peculiar.It doesn't fit the usual parameters so all models when they get to a picture more than 3 or 4 days out are struggling and painting unreliable pictures.
So making a statement based on scatter in a gfs ensemble means nothing.

Thats probably what kippure meant.

pauldry

The UKMO is promising colder conditions for the end of January in their forecast with outbreaks of Rain Sleet and Snow. So it certainly wont be mild but the beast from the East may not return to such an extent it was here before either.

Duiske

Deleted User wrote: »

The weather set up is peculiar.It doesn't fit the usual parameters

That was seen many times during the recent cold spell. Its as if the models have a bias towards atlantic dominated weather patterns for Ireland, and when something out of the norm shows up, such as a cold Easterly flow, it adds a bit of confusion to the picture.

Its just takes a few days to get a handle on things.

Kippure

Rougies wrote: »

Can I ask why?

Each model atm is pridicting a some what differant outcome. It always happens when theres a change on the horizion. Ive been following a winter forecast on netweather with great interest, BFTP and rogers. (I,m sort of using there forecast as the control run for this winter).

At the moment the models should be picking up on a peak energy period from the 25th to 31st, stormy weather, But we,re not there just yet.

The gfs is showing a easterly with cold cold weather returning. What we want to see is at least 3 of the main models agreeing on what happens next roughly.

Also see BLack Briar and duiske posts.

Redsunset

There could be a hugh scandi high developing in the near future but the angle is not great then it sinks.

Bit too far out but could be a good trend forming.

Kippure

Kippure wrote: »

Each model atm is pridicting a some what differant outcome. It always happens when theres a change on the horizion. Ive been following a winter forecast on netweather with great interest, BFTP and rogers. (I,m sort of using there forecast as the control run for this winter).

At the moment the models should be picking up on a peak energy period from the 25th to 31st, stormy weather, But we,re not there just yet.

The gfs is showing a easterly with cold cold weather returning. What we want to see is at least 3 of the main models agreeing on what happens next roughly.

Also see BLack Briar and duiske posts.

Gem and ukmo are trending towards very cold easterlies.
The high is not far north enough though.
You'd have very low dewpoints but pressure too high at 1030mb for much precipitation.
Cue the ecm later.

All a tad too far out to prick more than a passing interest so far.
Theres no doubt there'll be many minor or major changes all of which might maintain cold but change the detail of a forecast greatly.

As I said Baby steps.

Would someone be so kind as to post up the ECM for me when it's out [DE maybe?].

Post up a few of them from say +96 right out to +144 and beyond if you can as I'll be on mobile internet and it will be handy not to have to look them up-cheers

As it stands we are looking potentially at a slack flow which means sub -10c night time minima will be back next week to finish the job on our roads...

typhooner

another Easterly progged for next week, almost certain to happen but with a slightly different wind Direction from our last North Easterly, talk of it being dry though are premature, we saw what happened during the last cold spell with pressure remaining high over the country but with showers coming in off the Irish Sea. I'd say Dew points could be even colder this time with the air coming from a very cold continent from Wednesday onwards

darkman2

I will put up the ECM charts as they come out from 96hrs in a about a half hour or so.

Deep Easterly

Deleted User wrote: »

Would someone be so kind as to post up the ECM for me when it's out [DE maybe?].

DM2 has offered to do a running analysis on the ECM. Something to wet your appetite in the meantime from the UKMO:



Does not look particularly cold though, average to slightly below at best with the chance of a lot of st cu cloud. But personally I like it!

ninebeanrows

Deep Easterly wrote: »

DM2 has offered to do a running analysis on the ECM. Something to wet your appetite in the meantime from the UKMO:



Does not look particularly cold though, average to slightly below at best with the chance of a lot of st cu cloud. But personally I like it!

You'd be wrong there about the coldness, some serious cold banked to the east of England ready to move in.

Ahead of it the cold lower dewpoints would have arrived and it would feel bitter, already subzero maxima in britain.

However this is all fictional.

Snowaddict

Yes indeed it certainly is looking very interesting once again..

Notably, there are several developments at the 30mb level at the moment. The 30mb temperature has warmed in recent days, the latest update of the graph showing more significant warming with a vertically rising temperature trend in evidence. The warming may not be categorised as a Major Midwinter Warming, but it may just be enough to maintain a general displacement of the Polar Vortex & not allow it to become too organised. The overriding medium term NAO signal at the moment is neutral to very slightly positive.

30mb Temperature Graph



The Arctic Oscillation in particular is about to return to negative territory again & could well reach a steady value of -3 in the coming medium term.

At the moment the very interesting developments are at Day 6 & Beyond. There is certainly the potential and risk for renewed frosts developing during the weekend & into Early next week. Regarding the threat of more sustained wintry conditions, we will need to see a gradual dilution & removal of the somewhat milder 850mb temperatures that are currently being suggested on available Medium Term Guidance.

We are some distance yet from any certainty regarding a renewed Easterly outbreak, but the overall trend is there in the medium term for a return of colder, potentially even increasingly colder conditions as we enter the final third of January.

It is also likely that any evolution towards an Easterly outbreak will involve renewed Warm Air Advection from the Azores region into higher latitudes as a response to the NAO signal, combined with a Westward movement of the area of High Pressure that has been stationed over Siberia for the past 5 - 7 Days, to form a largescale blocking High North or Northeast of the UK & Ireland.

SA

darkman2

ECM 120hrs



Exceptionally cold to the East but the cold air remains in the North Sea at that stage.

Deep Easterly

Weathercheck wrote: »

You'd be wrong there about the coldness, some serious cold banked to the east of England ready to move in.

Ahead of it the cold lower dewpoints would have arrived and it would feel bitter, already subzero maxima in britain.

However this is all fictional.

That is true WC, but my concern was not about the temps in the UK, but here. That chart posted would suggest very near or slightly cooler than average at best due to cloud amounts.

darkman2

ECM gives some frosty nights but not a whole lot else.




FWIW I think it is overdoing the height increases from the South way too much.

Deep Easterly

As noted above, not a very interesting ECM run tonight. Average temps, with little sign of anything interesting weatherwise:



I would gladly sacrifice any hope of cold weather at this stage for something much more active. This winter has been very calm and very dry so far. Bring on the screaming Atlantic fronts I say, I have had enough of these doldrums.

nacho libre

don't be ridiculous paddy1;) if there is no sign of a storm on the horizion what's the point of atlantic activity again?;) anyway it looks like what patneve said several days ago about the azore high merging with the high to the east maybe about to happen.

Bishop_Donal

7 day wind outlook attached.

http://magicseaweed.com/msw-surf-charts2.php?chart=1&res=750&type=wind&starttime=

Getting interesting again.

Deep Easterly

A chart from back in the days when we used to get something called weather:


January 1990 started out something similar as to what is being experienced right now. Colish type weather with occasional weak fronts skirting up along a big East Europe block. Later in the month, a more vigorous pattern began to become established and by Feb, gales and storms became frequent, intense and often very destructive. I vaguely recall one particularly stormy night from this period when we with no electricity as as violent gale, with hail and thunder roared outside.

Those were the days....:)