Captain Shortwave

All models have an east/north easterly developing early next week; After this looks complicated due to some shallow lows running along the subtropical jet stream as well as cold pooling sinking south from a rapidly sharpening Atlantic trough. Good luck modelling these interactions accurately at this range. I will say that I would put high confidence that any resulting low will probably be weaker and more elongated than the current solutions on offer. This doesn’t mean that the location of said low will be conductive to cold/snow for the uk, though a shallower system would obvious give a higher chance of a positive outcome.

Fair to say the 12z suite is worth some raised eyebrows (all three of the main models with an easterly developing early next week, that could be capable of delivering wintry showers). No guarantee of this actually occurring and of course the longevity of any cold weather, but that looks encouraging to say the least.

We were due a stormy mid-autumn, that said the coming period isn’t really that normal given we are seeing stormy conditions at the same time as seeing heights omnipresent to our north. The storm for Thursday looks like a tough one to model given it will deepen and then dumbbell around the parent low before becoming one discreet system. At the moment it could bring severe winds anywhere from the middle of France to northern England, on the other hand it could become absorbed into the parent low quicker and not be so much of a problem. Rain looks being the more definite problem, even today there is a near endless supply of moisture pushing out of the English Channel and with low pressure tracking further south compared to normal, then England and Wales look like baring the brunt of the rain in the coming days.

I am a little surprised to have got over 60mm of rain over the last day or so. Seems that on the whole the Peterborough area coped fairly well, there was some localised areas with high water level but they were all placed where this is allowed to happen to spare other areas. It has been a strange Autumn. A lot of warm and dry weather, but we have also seen some very wet days and of course a rather early frost for the time of year. Awful conditions over Suffolk though, we certainly don’t want a westerly dominated winter given our starting point in regards to water levels.

Very wet today and the river Nene is looking pretty high. Avoided the worse with people at work commenting of flooding up in Lincolnshire (Which we also cover).

Initially it seemed like windward coasts would get the worst of the conditions, now the easterly seems to have been lessened (especially further south where that chillier airmass never arrives). Now we are face with an area of low pressure becoming slow moving across the UK and much larger amounts of uncertainty regarding rainfall. GFS up to Saturday evening; Southern England looks pretty bad along with an area from the Firth of Forth to Aberdeen. Arpege Aside from Eastern Scotland, this shows a very different story. Eastern areas are badly hit whilst towards the south west things are not too bad. The red warning looks right but aside from Western Scotland (Which looks like escaping without much rain), any other area could be given a proper soaking depending on the behaviour of that low. Original post: https://community.netweather.tv/topic/99428-model-output-discussion-mid-autumn/?do=findComment&comment=4938972

Initially it seemed like windward coasts would get the worst of the conditions, now the easterly seems to have been lessened (especially further south where that chillier airmass never arrives). Now we are face with an area of low pressure becoming slow moving across the UK and much larger amounts of uncertainty regarding rainfall. GFS up to Saturday evening; Southern England looks pretty bad along with an area from the Firth of Forth to Aberdeen. Arpege Aside from Eastern Scotland, this shows a very different story. Eastern areas are badly hit whilst towards the south west things are not too bad. The red warning looks right but aside from Western Scotland (Which looks like escaping without much rain), any other area could be given a proper soaking depending on the behaviour of that low.

A lovely sunny day, it felt chilly in the shade but not too bad in the sun with light winds.

Well this is going to feel pretty darn raw, also that cold pool will certainly allow showers to drive in from the east. Shame we are not in a period where this could realistically deliver snow because that is a fine easterly. An interesting change from the prolonged warm period we have seen. Longer term trends suggest that the pattern may return back to what we have been seeing recently (winds backing towards the south west), but there will be uncertainty regarding how long (if at all) we maintain that undercut through southern Europe.

This coming weekend does look decidedly cooler thanks to a polar maritime airmass. It does look like there is potential for some widespread grass frosts and wintry showers over higher ground. It will be a big change from the current conditions (especially in the south). Next week looks rather uncertain, the surface high looks quite chilly (At least to start with), if we can fully undercut the ridge that will push eastwards then a cut off high and an easterly flow is possible (this could keep conditions pretty chilly and showers could be quite potent given the warm sea temperatures), however it is also possible that winds could back southerly again and see temperatures recover back to near normal with dry conditions in the east (I think this weekend will properly end the summer like conditions that have persevered over Western Europe through most of the Autumn so far).

Over an hour of intermittent lightning during the evening, not a bad effort, the event felt a little patchy with rain coming and going so it wasn’t overly wet.

I just saw a big flash of lightning to the west/south west of here. Hopefully we will get a few more as this rain moves through.

It would be quite a series of events to generate a push of warm air as intense as what could occur in around 6-8 days time. Firstly there seems to be a late heatwave over Iberia followed by this potentially pushing north thanks to a deep Atlantic trough. The key interaction appears to be around day 5 Ex-Tropical system that is likely to interact with that Atlantic trough. In particular at this point the cold pooling is moving southwards whilst the low is ambling directly in this path. Get this interaction and we see the trough dig even further south, which aids to building of the Euro ridge and subsequently northward advection of unseasonably warm air from the south. Only worth noting but of course seeing 850s between 15-20c is something that is very rare or even unheard of, yes you can get TM air masses of around 15c or so but a southerly flow would be quite something. Worth watch but again if it did happen it would also require a strong enough surface flow from the south to gain any real warmth at the surface.

There does seem to be scope for next weekend to be pretty decent with a ridge building across the south of the UK. ECM ensemble mean There are differences between the models in regard to how strongly the ridge influences our weather. For example the GEFs favour a flatter pattern. So it remains to be seen as to how settled conditions will get, though more mixed conditions are expected the following week again. Before then, Wednesdays low still looks likely to bring strong winds, initially through the Irish Sea and potentially transferring through Northern England and Southern Scotland. Though the track and how the low is handled could change, the low is expected to deepen rapidly but will substantially ease off and at the moment this transition seems to happen whilst the low crosses Ireland and the British Isles, if the low continues to deepen as it travels through the UK then the outcome could be worse than currently modelled, on the other hand it could ease earlier and only bring a windy day but nothing too severe.

At the moment the most certain aspect is that temperatures will be close to or a little above average given the prevailing west/south westerly flow. I would also add that the south will probably be drier than average with the north closer to normal or even above if we get a front straddling the north west for a prolonged period. There is the chance of temperatures reaching the mid twenties early next week as the winds back more southerly, there is also the chance of some strong winds at times either from our own systems in the North Atlantic or ex-tropical systems deepening as they interact with the jet stream.

Early cloud has cleared and it is at the moment sunny. Not sure what we will get from the cold front, there does seem to be some scope for something quite active (though it will probably not be thundery). As for last night, I think the storm was losing some of its electrical activity by the time it reached here, still there were a few decent strikes.

Not much thunder and lightning but there have been a few close CGs that have meant that I am certainly not sleeping through this.

If something does end up reaching here, I hope the low cloud and mist will shift to allow a proper viewing. I am a little surprised in regards to how quickly the low cloud filled in the gaps this evening given the wind is technically offshore from the east/south east.

The long wave pattern for week 2 seems to be heading towards Atlantic trough/strong Euro high. We shouldn’t rule out the chance of some very warm conditions occurring at the end of the month. ECM day 7 GFS/GEM Pretty good agreement for that Atlantic low to throw up a ridge ahead of it. Can we get the amplification to veer the winds southerly rather than a broad south west flow.

Not a bad day today, still rather pleasant with a gentle north to north east wind and plenty of sunshine.

A lot of uncertainty regarding the weekend. The first element is on Saturday in regards to where the line will be drawn between a rather chilly north easterly across the north and a very warm and humid east/south easterly across the south. GFS shows how stark this could be The second element that occurs on Sunday is how extensive any rain is and how far east this progresses, if the east stays fine with some sunshine then again the high twenties is possible with winds from the south east. GFS prediction A muggy 25c in the east but even here it is partly cloudy skies and some rain. Any model that shows the high being more resilient could yield higher temperatures than this.

Increasing confidence that low pressure will probably sit to the south/south west by the end of the week with a cyclonic but warm flow draw up around this. Conditions will not be like the past week or so, but the chance of very warm conditions and the potential for thundery downpours to drift northwards at times.

Some low cloud this morning, but this should clear and break up relatively quickly. A decent and warm day today with good sunny spells and just the chance of a shower in western areas. Temperatures could reached 27c in eastern parts of the region, more generally around 25c.

Very little certainly for next weekend, fair to say the pub run is quite different again; A lot of warm and humid air spreading north, the potential for temperatures to hit the high twenties in any sunshine, the potential for a lot of rain and thunderstorms pushing north from France. Very hard to see the trend and obviously this could swing sharply back to something flatter or potentially something further west, which of course could be quite a remarkable change in fortunes again.

Probably the last 30c day this year, the highest temperature was Cambridge today at 32.5c. Quite a spell of heat, especially for September, to get seven days in a row, four of which exceeded 32c (and one day only missed out by 0.1 of a degree). Add in some quite intense thunderstorms in places too to round things off.