IanT

Looks like the phrase “writing does appear to be on the wall for a cold Christmas” was misinterpreted…

I agree. The MetO forecast for this region was accurate and timely, given how the system played out. The warning was given - and was being questioned on this site! - in good time. We seem to have an increasing tendency in this country to blame the authorities for everything that happens. Viruses, energy/food costs, a few inches of snow..! Stuff happens… Sites/communities like this are full of people taking personal responsibility for understanding how weather (at least) might impact them. I think that is laudable.

Perhaps the snow fell somewhere else? That could explain it.

Yes - very hard to see what might shift the whole system southwards no. I’ll be happy to be proved wrong! So you said! Actually - it’s a decent effort, well done.

Not sure I remember that forecast!

Mild chasers on NW… FullSizeRender.MOV

I agree with this. Take a look on the excellent NW radar. The track/pivot-point of this looks a little W of where some of the models have it. Worth watching, as you suggest.

Does model output start at T+144…?

So…. Forecaster Nick is forecasting the forecast, and you are commenting upon his ability to predict what the predictive model is predicting? Just making sure I’m keeping up here!

The “get the cold in” crew have their wish. But the charts are reminding us that the cold - in itself - isn’t enough for lowland snow. It is a necessary pre-condition for a notable wintry spell, but it is no guarantee. That said, small features can arise at short notice with outstanding results. All to play for in this regard, with attention better focussed on the detail in the next 168h rather than on predicting the breakdown somewhere out in FI.

Could parts of the SE see patches of freezing fog early Saturday and Sunday mornings..? On occasion this can be quite a (dangerous) spectacle.

….or, that the range of potential outcomes is still quite broad.

NWP output this morning says “lower for longer”. A stark contrast to the global macro (financial) models that form my day job….. Longevity is being bought this morning, over precipitation. A decent trade imho.

Dog_chases_ball.mov Netweather users chasing the snow “event” at T+168…

The latest on the low from Atlantic 2-Day Graphical Tropical Weather Outlook WWW.NHC.NOAA.GOV Emphasis is mine. A large non-tropical area of low pressure located over the central subtropical Atlantic about 900 miles northeast of the northern Leeward Islands continues to produce a large area of showers and thunderstorms. This activity has become somewhat better organized this morning, though frontal features remain attached to the low. Environmental conditions appear marginally conducive for development and a subtropical or tropical storm could form within the next day or so. By Friday, the low will move northeastward over cooler waters and interact with a mid-latitude trough, limiting the chance for additional subtropical or tropical development of the system. Additional information on this low, including warnings, can be found in High Seas Forecasts issued by the National Weather Service. The next Special Tropical Weather Outlook on this system will be issued by 9 PM EST Wednesday, or earlier, if necessary. * Formation chance through 48 hours...medium...50 percent. * Formation chance through 5 days...medium...50 percent.

Took me a while to work that image out..

The NOAA analysis suggests that the low may be less developed than is modelled, as it is subject to some disturbance during its formation. Perhaps that means it will be weaker?

Which will prove to be the strongest feature on the charts? The block or the incoming low? That is the question…

Yes. V keen to get NOAA’s view on the M4 divide next week…

Atlantic 2-Day Graphical Tropical Weather Outlook WWW.NHC.NOAA.GOV 1. Central Subtropical Atlantic: A large area of low pressure located over the central subtropical Atlantic about 800 miles northeast of the northern Leeward Islands continues to produce a broad area of showers and thunderstorms. Environmental conditions appear marginally conducive for development and a subtropical or tropical storm could form in the next couple of days. By Thursday night or Friday, the low will move northeastward over cooler waters and interact with a mid-latitude trough, limiting subtropical or tropical development of the system. Additional information on this low, including warnings, can be found in High Seas Forecasts issued by the National Weather Service. The next Special Tropical Weather Outlook on this system will be issued by 9 PM EST tonight, or earlier, if necessary. * Formation chance through 48 hours...medium...50 percent. * Formation chance through 5 days...medium...50 percent.

Looking at the output of the last 24h I observe that the greatest uncertainty attaches to perhaps the strongest feature on the Atlantic charts. The development and course of the low may be the determining factor in how everything plays out beyond the next few days. All eyes to the SW…

Because the model output today is so good..!

I’ve spent a long time looking at the output across the various models. Winter is coming.

Sadly we are closing fast on the point where the only way forward in terms of modelled weather is downgrades…

It is always fascinating to see posters queueing up to say that the “…models are struggling…”. I assume this comment is based on the lack of consistency in model output. Whilst there will be only one resolution, at this point multiple evolutions are possible - as reflected by model output..! Don’t be too quick to conclude that models are struggling because their output is inconsistent. It may be better to recognise that there is still significant uncertainty given the set of starting conditions.