Penellype's Weather Channel

[Penellype]

If, like me, you don't like the heat, make the most of the next few days. With each run of the models the medium term outlook seems to be getting hotter and hotter, and not just for a day or 2:



Not much rain on the menu either

[Penellype]

I mentioned that the models seem to be getting hotter with every run - here is the latest temperature map for a week on Friday, hot off the press:



And here comes Saturday 28th:



At this point the model starts producing forecasts for midnight and midday - midnight, bizarrely, is hotter.

Midnight Sun 29th:



Midnight Mon 30th



You can usually add a few degrees to these temperatures as the GFS tends to underestimate them

Plenty of time for this to change, but this would be a serious heatwave. I may emigrate to Iceland!

[1Bee]

:-o

Good grief, that's something...

[Lumpy]

Thanks as always Pen.
You did mean midday and not midnight for the 29th and 30th. Please say you did.........pretty please.
X

[Penellype]

Thanks as always Pen.
You did mean midday and not midnight for the 29th and 30th. Please say you did.........pretty please.
X

Sadly not. Because it takes time for things to heat up and cool down, the temperature can be hotter at midnight than midday. The coolest time is usually around or just after dawn.

It is very unlikely that it will be as hot as this, although some of the runs continue to be very hot. The ensemble chart for the screenshots I posted (which wasn't available at the time) shows that the operational run (thick green line) was an outlier, which is hardly surprising:



There is also a good deal of scatter at this point, illustrating a high degree of uncertainty, and some of the runs are quite cool. The latest chart is more sensible, although any of the lines that get near to the 15C level are pretty hot:

[Lumpy]

Oh pig poop!

[Lumpy]

Pen if it could be those temps at night what could it be during the day as a worst case scenario?

[Penellype]

Pen if it could be those temps at night what could it be during the day as a worst case scenario?

Honestly, I don't know. I think that scenario is very unlikely anyway, but temperatures in the low 30s are quite possible next week. As always, everything depends on the exact position of the low pressure in the atlantic, which is sucking the hot air up from Africa in this scenario. The most likely outcome, what usually happens, is that the hottest air ends up in France.

[Penellype]

I think York has a rain repellent coating at the moment:



Although it looks like its raining just to the north of York where I am, I can assure you we have not had a drop of rain all afternoon despite a very threatening looking radar picture earlier.

Please can I have some rain? Pretty please...

[Chippy Minton]

Funny isn't it. SWMBO has just driven from Manchester to Beverley and said it was raining all the way (obviously avoided York). I drove from Manchester home in full rain but at home completely dry.

Need rain. We're in United Utilities, but 3 miles away is Severn Trent. I need a really long hose

[Penellype]

Models have thankfully backed off the extreme heat for next weekend, although it will still be warm or hot. The temperature forecast is much more sensible now...



However, the latest (6am) run of the GFS (above) goes crazy again around the beginning of August, and once again the higher resolution temperatures are off the scale:



Remember you can usually add a degree or 2 to these temperatures, which would put the white area at around 40C. I think that might be a UK record if it happens (unlikely).

There is a huge amount of uncertainty - this is nearly 2 weeks away, but there are quite a number of lines above the 15C level and some touching 20C on that graph for York. That's just nuts.

[FuzzyFeltDeath]

Love reading the updates Penellype, thank you very much.

I've amassed £10+ in goole credit via their survey's and I've nothing to spend it on.

Would you have an advance app for the weather worth buying, or are the like you use above all website with subscription?

[Penellype]

In general weather apps are not worth buying. All weather apps get their data directly from the models and the models are the same as the ones available on free weather sites. You are paying for the programming, layout and possibly alerts, but there is one big problem with all weather apps. They include no human interpretation whatsoever. That may sound like no problem, but in fact it is extremely important. Models are very bad at certain types of weather, particularly the exact location of showers, thunderstorms and snow. They will simply show rain and leave it up to you to decide whether that is a band of rain affecting the whole area or a few showers that are hit and miss.

The other issue with model runs, particularly at a few days distance, is uncertainty. The apps all use the higher resolution operational run, and ignore the other runs (members) of the ensemble. Sometimes the operational run is an "outlier", much the hottest, coldest or wettest of the ensemble. The weather app doesn't care, it uses it anyway. A human weather forecaster would take this into consideration in the forecast.

The websites I use are all free of charge. The main ones are:
https://www.theweatheroutlook.com/tw...datmdlout.aspx - charts from the GFS, ECMWF and GEM models, plus a few from the Met Office and the shorter range high resolution models, including the useful Arpege. Charts I post on here showing maps of pressure, rain etc are from here.
Wetterzentrale.de - Diagramme - the ensemble charts I post with the black background, which are from the GFS model, updated 4 times a day. Type in your nearest big town or city.
https://www.netweather.tv/live-weather/radar - rain radar updated every 5 minutes with about a 10 minute delay. The best of the various radar sites for up to date information about where the rain is and which direction it is moving in.
Real-Time Lightning Map :: LightningMaps.org - real time lightning map (a few seconds delay), showing you if a storm is heading your way. MUCH better than the lightning strikes info on the radar maps, and zoomable to a high degree.
https://www.gavsweathervids.com/ - daily videos, sometimes several a day, covering everything from short term forecasts to long range seasonal outlooks. An absolute goldmine of information from an amateur forecaster who really knows his stuff, presented in a way that is easy to understand and educational. If I want to know what the models are saying about the next month or season I go to https://www.gavsweathervids.com/long...sts-center.php, but I try to make time to watch the videos he posts every day. There is also a page of links to useful websites https://www.gavsweathervids.com/links.html which is a huge resource.

The only pay site I would consider signing up to is Expert weather for those who need to know more which is run by professional weather forecasters including Simon Keeling and Gary Nicholson. This would give more detail and depth than Gavsweathervids, but it is expensive at £13.95/month, and frankly I wouldn't have time to watch all the videos anyway.

I hope this helps.

[FuzzyFeltDeath]

Wow what an amazing post!

I had a quick look at a couple of sites and just assumed the extra details must have been paid.

Will have a good look at all the sites, as I've always had an interest, I know once I started I'll be obsessed for a while.

[Lumpy]

Pen,
I know anything more than a week away is subject to rapid change but do you with your vast weather knowledge think that this type of weather might come to an end in a couple of weeks?
Our thermometer, in the shade is reading 32C at the moment and the local news is saying that the heat is just practicing for Thursday or Friday.

My OH has severe chest problems and the heat is making him virtually immobile.
X