Eagle Eye

He's retired from forecasting.

Here's my discussion for tomorrow. Working from 9 till 5 so best to put it here now even though Jay hasn't done the actual map yet. There are a couple different modes and timings with these potential storms. I'll start with the most likely but also has the smallest ceiling of potential. Ahead of a cold front, with fairly good DLS, showers and storms should form in Ireland and up into parts of western Scotland. These happen mainly throughout the afternoon in a stream along an area of 500-1,000 J/KG of MLCAPE along a tight PV lobe. With weak MLCIN and a fairly good trigger with PV lobe induced low-level convergence. This occurs with fairly high moisture and fairly weak saturation. So, all showers and some weak to moderate storms may well form. High LLLR's and strong 3CAPE (100+ J/KG) allows for some small severe hail to form, potentially around 1-1.25 inches. There is potential for locally 2,000+ J/KG of MUCAPE and combine that with the large inflow layer and you could suggest, strong updraft speed for strong downdraft speed, however, weak downwards momentum within storm soundings will mean that downwards momentum won't be a particularly high percentage of the updraft speed and with restricted inflow strength, so hail is still going to be restricted compared to updraft strength. Strong buoyancy will help the hail, however, there are a lot of anti-severe hail factors mentioned before that keep it from being a significant factor in anything other than increasing updraft width+speed but not necessarily much of the downwdraft speed for the hail size. Moving onto the Wales and the midlands-northern England part of the risk. There is quite strong capping in place and no real trigger. However, 2400+ J/KG of MUCAPE in places with widespread 1,000 J/KG of MUCAPE in an area of tropical moisture rates means that with fairly strong DLS, any low-level convergence available via localised orographic features or something like that, could spark a few severe isolated thunderstorms with a small chance of becoming a Supercell. Again, this happens in the afternoon and if storms can get going then it would be mid-afternoon initiation and into the late evening for storms. Good buoyancy with a large inflow layer and good sub zero CAPE suggests some 1.5 inch hail is possible. The hodograph isn't really your typical C shape with the inflow which is fairly strong but still leaning towards the moderate side and so the hail is still being restricted to about 1.5 inches. The inflow layer is large compared to recently but still relatively small compared to events larger than 1.5 inches. Storms could potentially reach past 12km cloud tops which is quite high compared to your everyday thunderstorms, hence why they could be quite severe. Finally, in the evening and overnight in the SW, some elevated thunderstorms could form. Not particularly large CAPE but good moisture and good modelling guidance suggests, these should happen. Previous events suggest some good lightning frequency potential as well. Here's the current idea that Jay has but he's waiting till tomorrow which is fair enough but I can't do; (black outline is area of interest for lightning and also in my opinion, the severe outline I would think of as well.).

Any difference in environmental temperature or pressure enough for it to become a front or a trough. A shortwave trough or any front. To be more specific, there are other ways for or to occur though, anything that works to make low-level convergence and upper-level divergence can work as a forcing. Something like a jet streak (just research, it's pretty simple) or PV lobes that I often over talk about. Along with moisture advection near the surface forcing moisture convergence. Then there's the most complicated gravity wave, which is rare here. Those are ones other to fronts and troughs that work.

Sorry about no forecast for today earlier. Absolutely shattered and Jay wasn't available to do the map. Proper professionals.

Lifted condensation levels. Entrainment CAPE is calculated using the LCL and equilibrium level. LCL is cloud height. For larger hail events you want cold 850's meaning good low-level lapse-rates. Don't know any specific numbers but it's a reason why spring tends to have the best hail events. Though high CAPE can counteract that 850's being warm scenario.

Could do. High LCL's weakens entrainment CAPE and with it being so warm sub cloud level, hail won't be as strong as analogs and they might not be accounting for the height. Those 850's aren't really typical for larger hail events. Given the 2 inch analogs, some people might say that my 1.5 inch forecast was very conservative but I think it was actually pretty high end.

Sorry for the late forecast. Made this earlier today but was waiting for Jay to do the map. Was playing cricket so couldn't help him when making it either. Convective Outlook ️ A large Theta-E airmass advection will allow for near tropical moisture rates along the Irish Sea and the coasts of Eastern Ireland and western England up to western Scotland. 1000+ J/KG of MLCAPE looks to advect and create showers and storms Wednesday night/Thursday morning, with potentially frequent lightning in some of them. They will move roughly north as it goes into Thursday morning. This kind of saturation and moisture levels tends to allow for very frequent lightning once the cap is broken. If the capping isn't broken then it's a bust but it looks fairly likely to break and so some storms around the previously mentioned coasts could have quite frequent lightning rates. Further into Ireland may see some scattered storms at random points throughout the night. These may have fairly frequent lightning, having good lapse-rates along with near tropical like moisture amounts and fairly good MLCAPE. 850's Theta-W at 16°C+ is enough for the elevated storms to form. Lots of elevated CAPE and good hydrolapse rates continue to suggest frequent lightning rates at times possible. The inflow layer is fairly large with good below zero CAPE. Along with good hydrolapse rates and a supportive hodograph, severe hail is quite possible. Hail could potentially be up to 2 inches but it's probably unlikely to reach it's potential but I suspect some 1.5 inch hail is possible. Some surface flooding is also possible. Timing wise and it's on Wednesday night, storms should form in the southern part of the Irish Sea and into the SW of England, moving north towards SW Scotland potentially by around mid morning. These storms will be mostly longer-lasting pulse-type reaching 9-10 km before new storms should form after one falls. They might form into a weak but wide MCS with some near severe wind gusts depending on DCAPE strength.

Iso settings can be quite awkward on camera, I think I used 80 or something like that for this and use that for most so that close strikes are in detail. Though it depends on there being lots of CG's and detailed strikes. I also use my phone and sometimes my other camera to gets as many iso settings as possible.

We're feeding on scraps from the models. Meanwhile, the models aren't showing scraps in the Mediterranean. Imagine if that sort of thing came here.

Im going to be riding on the "possible Supercellular characteristics" forecast for a while.

Mentioned the possibility of Supercellular characteristics yesterday or potentially a Supercell. Not a Supercell but definetely had the characteristics of one to be fair to me.

Well, as we get closer to Winter (I can dream). The tropical forcings become very interesting. The blocking signals will be increasingly important. Just thought I'd talk a bit about some of them. The Uralian omega block is typically forced by MJO signals we don't like here if I remember correctly, it's been a while. It's a Rossby wave which can tilt the Stratosphere in our favour however. It's a large driver of upwards coupling with increasing Eddy vector strength. Almost everything in the atmosphere is transferred through heat signals driven by waves. The Siberian high and Aleutian low is a very good signal you want to drive significant Stratospheric change with wavebreaking. That wavebreaking could well then force it's way down to the surface depending on the zonal winds. Then there's also the Scandinavian high. The Alaskan high can work but I seem to remember being told that doesn't typically end up too well for us. Greenland doesn't seem to be as big of a forcing factor recently but it can be (2010 I think?). Most of us then know to look out for the Greenland high and Scandinavian blocking. For that we know that we want +VE AAM and favourable MJO conditions. Then a bit of luck as well. So that's the basics getting ready for Winter. They'll be a lot more to talk about closer to time though. In Autumn, there is the added complication of Hurricanes to forecast intraglobally. I'm better at long-term forecasting unless it's thunderstorm forecasting pretty much. So, I'll just talk about what I know. Using CCKW's to forecast, you can help visualise the redistribution of the 'energy' from MJO wave production for Kelvin-Rossby wave phasing forecasting. Late Autumn is when we start getting interested mostly on how any Hurricanes will affect us. Hurricanes are most likely to form in the Atlantic with an easterly African wave and strengthen properly when it meets a CCKW. These can be identified with VP anomalies. Typical formation is post westerly VP anomalies and the start of easterly VP anomalies. So, these will become more interesting towards the end of Autumn when the Kelvin-Rossby interactions increase. There's lots of possibilities in how they interact and you'll probably have to use the tropical-extratropical interactions map and your imagination to give you the best guidelines for future forecasting at that point. A big positive right now is that, the QBO appears to be descending properly into easterly at the right time. Which is a good sign at the moment for cold lovers though we'll have to take into account a lot more teleconnections closer to time and I don't think the QBO is as big of a forcing as some people seem to think.

What I should've said is Supercellular characteristics. Fairly good and well rooted lift increasing updraft, though weak SRH values due to limited inflow layer space and strength. That will weaken Supercell prospects. However, the 3CAPE is decent and with hydrolapse rates post PBL that strong, that's a Dixie Alley esque saturation setup. CAPE is not particularly limited to post PBL despite the dry surface layer setup and post PBL, the slight warm nose does decrease CAPE availability, I suspect a less warm nose here would put it more in the noticeable category. A near surface LCL also suggest large amounts of available ECAPE which increases Supercellular potential and also Supercellular characteristics potential. Hail wise and there's good ECAPE with the near surface LCL's and fairly good EL's if the AROME is correct here. That mid-level dry nose does weaken storm potential as it's a bit too much. However, with more CAPE that is a Supercell potential. More energy into the storm can actually be used as a Supercellular indicator, especially given that the DLS isn't that far away from being a straight hodograph, it's in-between that and multi-cellular esque. Large DCAPE suggests a fairly good downward transfer of energy however, so a lot of the storms energy will be outflow dominated with the weak and shallow inflow layer meaning Supercellular potential sort of stops there. However, as you can see, it wouldn't take too much of a difference in moisture advection and where the energy is distributed to form a Supercell. Then there's this one, very similar with better inflow but a similar layer strength. Along with increased DCAPE. It's really only where the energy is distributed that's making this a multi-cellular or longer lived pulse-type event. Some slight variations and it's Supercellular.

Convective Outlook In southern Ireland, 400+ J/KG of SBCAPE will allow for storms to form. This will occur on the southern tip of the Theta-E loop. That's a typical area from these showers and storms to form with rapid surface based-PBL parcel-temperature difference advection from the south into moist air. That creates a localised area of lift forming showers through forced points with the best mid-level cold pool advection. These showers will form across southern Ireland late morning-early afternoon and moving SE. In the SE of England, throughout the day there should be a pool of 800+ J/KG of SBCAPE. With large DLS, there's a small chance of a Supercell but it's unlikely. There's also a chance of a funnel cloud. Small hail is possible in both areas. Along with some weak surface flooding. However, both should keep with non-severe strength in both areas.

Convective Outlook ️ A front will track East bringing heavy rain & the odd risk of an isolated lightning strike. Intense showers will develop in Ireland with a risk of sporadic lightning. A warm front will allow elevated showers to develop in the channel tracking E/NE. (Jay wrote the discussion. I didn't even realise there was a chance)

At what point does it become a Derecho.

From earlier today. YouCut_20230827_153202450.mp4

Really did look like a proper tornado ha ha. Wasn't though. The scud above really completes it.

Smoke tornadooooo

Convective Outlook ️ Intense showers will develop across Eastern England bringing the risk of sporadic lightning possibly the odd thunderstorm.

Hotel in Linz. Český Krumlov

What it was like 10 minutes later.

Storm nearing Rosenheim.

Some bits off of my camera today so far. P1250069.mp4 P1250419.mp4

And me lol