IanT

18.5c according to my car just now..!

An outstanding idea for those tasked with promoting the climate crisis concept.

I’ve discussed this before - it’s what I call the “mostly harmless” problem. Whilst [low prob x high impact] and [high prob x low impact] are the same in EV terms (so useful for insurers etc) they aren’t the same when preparedness is the key outcome. In simple terms these two axes shouldn’t be reduced to one dimension (colour) because too much valuable information is lost in the final transformation. I like the matrix, but not the colour overlay. Perhaps retain the matrix but go with a “PxI” labelling system where P(Probability) is Low(L), Medium(M), High(H), Very High(V) I(Impact) is Low(1), Medium(2), High(3), Extreme(4) So Isha would have been “upgraded” to an V4 for a limited area late last night. Why? Because most people don’t need to make special preparations for high probability / low impact events, but they should for a low probability / high impact events. At the moment these two scenarios both end up being called Amber. That’s where the loss of valuable information occurs.

Agree 100%. The most impressive aspect of this storm (so far, I am mindful of the red warning just out) is the sheer scale of the wind field. Across southern Britain - based on posts here and my experience driving from Surrey to S Wales between 1900 to 2120 - the intensity has perhaps been unremarkable. Some strong gusts and rainfall but not out of the ordinary.

Living the dream

I’ve driven from Woking to Cardiff this evening. A bit wet & windy across the Severn, but otherwise unremarkable.

GFS saying 102kph gusts for Cardiff, wildly out of line with the other models. Latest METAR says gusting 36kts (67kph).

It’s winter here in the UK. A storm can be a storm without being historic. A cold spell can be a cold spell without being historic - as we have just seen. Would it benefit us to return to a time when forecasts were forecasts without hype?

-6c here this morning. That’s cold for my location.

Alternative viewpoint: if anything is wrong - or anything changes - with the current NWP forecast output there is potential in all directions. Time for some butterflies somewhere to flap their wings

In the investment world we recognise what is called the “pain trade”. It’s the outcome least expected/favoured by the majority of forecasters; the outcome that few forecasters expect or want and that even fewer are positioned for. It’s pretty clear that the pain trade here - for both the NWP models and NW’s forecasting community - would be for the SE (& London in particular) to get buried later this week. The “French low” tracking N to deliver a headline dominating Cobra-level snow event in the most heavily populated portion of the country… Pain trade outcomes occur more frequently than expected, because outcomes in the tails of distribution approximations are - by definition! - unusual and hard to forecast. That’s why experienced/canny forecasters like the MetO take great care to allow some space for tail outcomes in their forecasting language. I think we can see that in action here…

…but 11 days away!

You make the mistake of discussing the actual weather. This thread is only for discussing the weather in the models

Plenty of forecasts made here, but I haven’t seen anyone making promises. Almost without exception posters say “The models show…” or “If this chart verifies…”. Interpreting such statements as promises is such a needy and immature character trait…

Too early for that! Clearly plenty here who are still looking/hoping for a good lynching opportunity