Ben Sainsbury

GEM and UKMO very very similar at T144, similar in a good way too.

Watching the model output today, I'm getting the impression that the low approaching from the south-west will almost definitely head across France and actually more of us may benefit from a series of shortwaves that develop NW of the UK, then moving SE across the country. I imagine these shortwaves will primarily consist of snow given they're embedded within the colder airmass. Interestingly however, for Bristol the GEFS 18z has a max snow risk of 28% vs the 12z at 25% and for London 34% rather than 31%. So there's still much to be decided with regards to that low approaching from the south-west. An exciting time for model watching regardless!

Couldn't have put it any better. As far as I'm aware only intervention that can be made before the model is ran is if any of the observational data appears erroneous.

Relatively speaking, a pretty good set of runs so far this morning. GFS and GEM producing a fair amount of snow mid-run, UKMO likely to do the same. Closer to the present, not particularly cold but remaining settled which is nice (imo). As mentioned before, still pretty large differences even at T120.

I second what everyone else is saying in that your posts are very insightful Scott and always greatly appreciated! Who cares about those who can't appreciate posts, they're irrelevant. We're all here for the same reason and that's to discuss our beloved weather. As you can imagine work is quite busy at the moment, but looking at the models it seems like around T120 is a key point at the moment. It's whether that initial push of heights towards Greenland is sufficient to set-up that northerly which then precedes the frontal rain/sleet/snow at Day 7. GFS consistently fails with that initial push and the resultant boundary of rain/snow is further north. The majority of the other OP models have a stronger initial push of heights towards Greenland which manage to hold, allowing colder air to get in place before the slider low moves across Southern UK. I feel we are on the right side of the boundary at the moment, but that may well change so will be interesting to watch.

I am no expert in modelling, but I don't really see why the EPS having the same resolution as the OP should result in more wrong solutions early on. One of the main reasons to have the EPS the same resolution as the OP is so they have the same ability to resolve smaller features. On a localised scale I guess this could lead to wider range of solutions regarding winds etc, but for the broader pattern I don't see why a higher resolution to previous would result in more "wrong" solutions early on. Sorry, not particularly helpful!

I don't disagree with you mate, it's not there isn't a chance that a random shortwave can prevent ridging into Greenland, I'm just not entirely sure that particular evolution on the GFS 12z is physically possible imo. But I definitely understand your scepticism, it's never easy to get a solid pattern for cold when you live in the UK!

To be quite honest, I'm not really that bothered which way the model output goes, it just seems a bit of a peculiar evolution to me. Of course, it is possible that we get a shortwave as the GFS shows, but with this particular run, the lack of baroclinic instability and an ever-weakening jet, I just don't see it preventing the high retrogressing towards Greenland.

Just a bizarre run from the GFS up to T216, not sure it knows what it's doing.

More of the fact as a professional meteorologist, we cannot jump to conclusions when looking at model output at T240. Our job is to consider all the possibilities and communicate this in a way to the general public that is easily understood. I think Liam Dutton does this perfectly in the tweet posted above.

At Day 5, it's behind ECM, UKMO and GEM. At Day 10, ECM is far superior, GEM and GFS close but GEM is marginally better. The IMD model is actually 2nd best at 10 days, but I am unfamiliar with this model. Maybe India Meteorological Department model? For those that would like a play around with the verification statistics themselves, they can be found here: GFS Verification: G2G All Models (ACC) WWW.EMC.NCEP.NOAA.GOV Original post: https://community.netweather.tv/topic/99706-model-output-discussion-into-2024/?do=findComment&comment=4996119

At Day 5, it's behind ECM, UKMO and GEM. At Day 10, ECM is far superior, GEM and GFS close but GEM is marginally better. The IMD model is actually 2nd best at 10 days, but I am unfamiliar with this model. Maybe India Meteorological Department model? For those that would like a play around with the verification statistics themselves, they can be found here: GFS Verification: G2G All Models (ACC) WWW.EMC.NCEP.NOAA.GOV

Looking at the bigger picture we have a Scandi high inside T72 with what is still a cold easterly with -8, maybe even -10 at 850hPa. We'd be shouting for this just a month ago! When we look forward at the possibility of the high retrogressing towards Greenland. It's a much more believable transition since we've already got the Scandi high in place. If we were under a zonal set-up with the same level of agreement for a Greenland high, I'd have less confidence than the set-up we have at the moment if that makes sense. I'm not saying the high will retrogress towards Greenland, but from experience this is realistic solution and with all global models generally on-board, it's difficult not to be quietly optimistic.

I think it's quite a good warning that the Met Office have issued. I'm not sure many people expect much from it, but there's definitely a chance that the models don't even have a good grasp even at this short range and that we could see a little snow more widely across SW England (given recent slight northerly adjustments).

Nothing but scare-mongering and is exactly why the Met Office get blame thrown at when there is this mis-information.

Looks like storm near Bath has undergone a right-split, with an uptick in lightning temporarily.

Seeing a few CBs flashing away as they're clearing NE'wards. Much better visibility now than earlier.

Tonight just shows why elevated thunderstorms are one of the most challenging types of weather to forecast. Mine and @Met4Cast forecast has been pretty poor to be quite honest and that's despite doing a full university dissertation on UK elevated thunderstorms

Some further developments on the far western fring of this large MCS. Maybe something even closer to home for us in Bristol/Bath/Gloucester next hour or so if it becomes electrified.

A lot of cloud and muck obscuring the occasional flashes here!

Both that and cloud bases being elevated too.

Thought the lightning didn't want to stray into international waters

Can see occasional flashes from cell N of Southampton from here!

With large thunderstorms being present earlier, there may be a bit of cold pooling about potentially? Unfortunately, I don't expect to see much/any more lightning from this mass of rain.

A number of elevated thunderstorms developing on the S coast... Not sure models were particularly keen in recent runs for this to happen. The amount of lightning in the channel right now is pretty nuts! Just shows never to write any event off too early.