Model Output Discussion - early October

[Jordan S]

A very wet day then for southern parts rain not really stopping in some places then later today the rain reinvigorates becoming heavy indeed across similar areas to the last 12 hours or so elsewhere today won't be too bad some cloud for the Midlands and Northern Wales but there should be some sunshine for more northern parts bar the odd shower.

 

Rain then sweeps north across most areas tonight lingering in central and Eastern parts not clearing until tomorrow afternoon perhaps quite warm for a time in the far south east but dependent on whether there's more rain here. 

Then potentially more heavy rain across Central and Eastern parts of England Monday daytime but some uncertainty over how much. Drier elsewhere with showers. 

The accumulated rainfall from the hirlam shows 25mm quite widely for England and this is on top of what's already fallen but perhaps another 40mm somewhere around London by the time this has all done that's not including Mondays rain. 

5 day accumulated rain to Wednesday night from the dwd Icon shows upto 80mm locally for some parts altogether so certainly a very wet few days to come especially in the south and west..

Edited October 12, 2019 by jordan smith

[knocker]

The ecm continues to shunt the Iceland trough south east in the latter stages of the run. Need to check out the EPS before further comment

[Frosty.]

As I mentioned several times yesterday, late october could be shaping up to become more benign / settled / blocked / pleasant and the Gfs 0z operational shows exactly that!

 

[knocker]

Rain currently from the SW > east midlands > East Anglia

[knocker]

Keeping in mind the latter stages of the ecm det run the EPS is certainly weakening the Iceland trough in this period with the subtropical high attempting to ridge north east. Not an earth shattering change at this stage but indicating more of a N/S split

But as we head into the ext period this trend continues ending with the trough to the north west  and a much weaker upper flow in the eastern Atlantic as pressure rises over the UK, So hopefully much drier for everyone, albeit systems are still likely to track across the north, with temps generally around average

 

[Frosty.]

The GEFS 0z mean is trending towards a more benign / pleasant / settled last quarter of october..as per the operational!

 

[Frosty.]

The Ecm 0z ensemble mean is also showing signs of improvement longer term, especially across southern uk with increasingly pleasant surface conditions....so, overall so far today the longer term signal is for a more benign last quarter of october, at least away from the far n / nw.

 

Edited October 12, 2019 by JON SNOW

[Methuselah]

Yes Karl, things are indeed looking up!

                  

Sort of:    

                

[Methuselah]

What a thoroughly splendid GFS 06Z at T+288!

   

Whether or not it (or anything like it) verifies is a different matter entirely, of course; but if it does, maxes of around 21C will certainly be possible!

Edited October 12, 2019 by Ed Stone

[Jordan S]

11 minutes ago, Ed Stone said:

What a thoroughly splendid GFS 06Z at T+288!

   

Whether or not it (or anything like it) verifies is a different matter entirely, of course; but if it does, maxes of around 21C will certainly be possible!

That would certainly feel very pleasant indeed after what has and what will have been so much rain before.

[Zak M]

GFS showing perhaps a warm spell heading towards the UK soon? 

[Methuselah]

1 minute ago, Zak M said:

GFS showing perhaps a warm spell heading towards the UK soon? 

I sure hope so, Zak. But the GEFS 06Z ensembles don't look too hopeful?

   

   

Will it firm-up, or will it disappear altogether?

[knocker]

Another example of different airmasses. Camborne close to the front with solid cloud all the way up and Valencia just a behind a trough and potentially very unstable and thus heavy showers

[summer blizzard]

Both the GFS and Euro this morning did indeed build pressure to our south and east at days 9-10 however caution is as ever advised at such range. 

[Jordan S]

Looks like the 12 o'clock gfs run is going with the dwd icons output that I showed earlier showing potentially some very heavy rain for a time during Monday particularly for central and southern parts of England it's then shown to linger until the end of Tuesday although showery by then still some heavier bursts mixed in..

but as you can see the next frontal system is already catching up with it for Wednesday. The rain Train keeps on coming..

Edited October 12, 2019 by jordan smith

[BlueHedgehog074]

In the Fantasy Island range of the modelling, so caution needed.... but the GFS 12Z tries to send the rain Train off the track as it shows a build of pressure late next week and early into the week after from the South:

 

[Jordan S]

5 minutes ago, DiagonalRedLine said:

In the Fantasy Island range of the modelling, so caution needed.... but the GFS 12Z tries to send the rain Train off the track as it shows a build of pressure late next week and early into the week after from the South:

 

It might just do it and shift some milder air northwards with it too.. 

[Methuselah]

Could be good for the October Fog Index? Better late than never!

   

[Zak M]

On Sunday morning a band of heavy rain from the south will drift northwards, reaching N Wales/N England by the morning. If you are under this band of rain then expect a really soggy start. The temperatures under the band of rain will be quite mild, and will range from 9-12c. Over in Scotland and Northern Ireland, where the drier places will be, it could be a quite cold start to the morning, with temperatures ranging from 4-8c. It could also be quite foggy and misty in Scotland to start the day. As the day progresses into the afternoon, the heavy rain that was progressing north will start to become more widespread, with the possibility of causing a few problems on the roads if it does become heavy. This rain starts to spread into Wales and Scotland. Northern Ireland on the other hand only has the chance of catching the odd shower, with some sunshine in between these showers. In the late afternoon, parts of SW England could also see the sun popping out. In the evening, the heavy rain should start to clear away, and parts of southern England could see some late sunshine to end the day. Parts of the north including Scotland and northern England will still keep the heavy and persistent rain, with some parts having the chance of it raining all day. The peak temperatures on Sunday should range from 10-18c in the south, and 7-12c in the north.

FAX:

Precipitation:

Jetstream:

Sea level pressure:

Temperature (max):

[MATTWOLVES 3]

And at long last according to the GFS 12Z operational, we have a build of high pressure to the South, meaning at least a temporary ending of this persistent rain and yuk... Temps look very reasonable in places also... Hopefully time to dry the ground out in time for the first freeze of the season..... Hopefully this is something that begins to show its hand in the coming weeks! Let's face it though, we could do with a drier spell now. 

[knocker]

The GEFS mean anomalies this evening are pretty much as has been indicated recently. A weakening and then elimination of the Iceland trough with a new tough over Greenland This results in a weakening of the upper flow in the eastern Atlantic and a pressure build in the same area. But although to some extent this looks promising the adjustment of the trough east does negate any significant pressure rise and portends a N/S split, This not drastic as pressure is still relatively high

[I remember Atlantic 252]

1 hour ago, DiagonalRedLine said:

In the Fantasy Island range of the modelling, so caution needed.... but the GFS 12Z tries to send the rain Train off the track as it shows a build of pressure late next week and early into the week after from the South:

 

imagine them in July, even lower chance of coming off then

[Methuselah]

Unfortunately, the GEFS 12Z ensembles do point portend the eventual arrival of some drier weather, though not necessarily toward any specific, lengthy settled spells...So, the most important question remaining is, of course: will it or won't it...snow in January?! 

   

   

[I remember Atlantic 252]

quietly keeping an eye on these last few FI runs of EC and GFS, will of course downgrade as settled weather often does, but EC 12Z decent again

[knocker]

Although the trough that drops into the NW Atlantic later tonight and intensifies as it slowly tracks south east, is filling west of Ireland by Thursday midday, it is still liable to result in three days of quite unsettle weather for the UK