South West/Central Southern Regional Discussion Discussion 23rd July 2013 onwards

[MrNooo]

I don't know if anyone else has spotted this yet, but here I can see some unstable looking mid level clouds to my south. I think they are known as Altocumulus Castellenous or something.

 

I wasn't expecting to see these types of clouds around today so I wonder if this maybe a good sign for something thundery later somewhere.

 

Yes, just had a band pass over here, quite what type of cloud they were I know not but did look like AC

[AWD]

More floccus type clouds here. Possibly a precursor for some overnight activity, well at least the Beeb forecasts suggested the chance of something happening. If anybody has some CAPE or LI charts out to tomorrow morning, maybe that is where the likelihood of Thundery showers exists.

The Cap gets eroded during the overnight period and more especially into the early hours so some showers are possible during the early hours into tomorrow morning.There is a small risk that these showers could be thundery in parts of the region tomorrow morning too.I'll await the 12z output to elaborate on this though. Edited August 1, 2013 by AWD

[gottolovethisweather]

Well I'll be damned, I thought 28c or so was the highest Maximum that I would achieve today but the rise in Air Temperature, as others have stated is very rapid indeed.

 

The skies cleared around 8am or thereabouts and the AT was only 17c at that stage. By mid morning I had reached 20.4c, hence my pessimism. Since 10:30am however, I have rocketed up to 29.2c as I type. In fact, the AT has risen 5c in the last two hours. Obviously this scale of progress should peter out somewhat but I can see me reaching 32c/90f again, at this rate. All this, in spite of only 17c uppers, whereas its 20c uppers or thereabouts over parts of the Southeast.

 

A very warm and hopefully potentially thundery night ahead of us.

[Polar Bear]

The Cap gets eroded during the overnight period and more especially into the early hours so some showers are possible during the early hours into tomorrow morning.There is a small risk that these showers could be thundery in parts of the region tomorrow morning too.I'll await the 12z output to elaborate on this though.

Please not more showers...not until my roof is fixed! BTW on the temps front I see some parts of Surrey I think have hit 34...I am sure that is what I saw. A warm 30.9 in reading ATM, and a breeze too which is interesting.

[ARTDEMOLE]

Reading 31.4c Here on top of the hill.. Humidity 495. Pressure 1008.6  hpa. Only a light  1.1 km/h  breeze

[AWD]

Please not more showers...not until my roof is fixed! BTW on the temps front I see some parts of Surrey I think have hit 34...I am sure that is what I saw. A warm 30.9 in reading ATM, and a breeze too which is interesting.

A one and only snapshot at 11am tomorrow morning from the in house NMM model;

[SunnySouthCoast]

Lovely sunny day & currently 28C here on the Costa Del Solent

[wimblettben]

Well I'll be damned, I thought 28c or so was the highest Maximum that I would achieve today but the rise in Air Temperature, as others have stated is very rapid indeed.

 

The skies cleared around 8am or thereabouts and the AT was only 17c at that stage. By mid morning I had reached 20.4c, hence my pessimism. Since 10:30am however, I have rocketed up to 29.2c as I type. In fact, the AT has risen 5c in the last two hours. Obviously this scale of progress should peter out somewhat but I can see me reaching 32c/90f again, at this rate. All this, in spite of only 17c uppers, whereas its 20c uppers or thereabouts over parts of the Southeast.

 

A very warm and hopefully potentially thundery night ahead of us.

These are some pictures of more unstable looking clouds to my South and Southwest which have just showed up around 4:00PM.

 

https://forum.netweather.tv/gallery/image/18810-unstable-mid-level-cloud-2/

https://forum.netweather.tv/gallery/image/18809-unstable-mid-level-cloud-1/

 

There is a whole group of these coming over my way right now.

 

I would say going by these clouds that as long as the instability carries on later tonight when the Cap breaks then we could quite easily have some thundery outbreaks of rain around overnight and into tomorrow.

[AWD]

From Ian;

"Still a warm story tomorrow but temps slide down from today's highs with potential for some scattered storms PM in parts of W Country"

[MP-R]

Simply stunning day today - so nice to have the heat back yet such a shame it'll be gone as quickly as it arrived. 

[Bristawl Si]

Simply stunning day today - so nice to have the heat back yet such a shame it'll be gone as quickly as it arrived.

Agree with these sentiments.i'd love a 3-week heatwave in August

[Andy Pepler]

you can keep this heat ..makes me feel yukk ...but i would like more storms please

[AWD]

I'm going to split this forecast into 2. One for tonight and one for tomorrow as developments tonight could be key to developments tomorrow.

Tonight's forecast map;

The area in red, which includes Cornwall, South Devon and along the South Dorset coast will see some light, sporadic rainfall through the late evening and into the early hours. I'm not expecting this to be anything more than light, sporadic rainfall though. Cloudcover will increase over Cornwall in the next few hours ahead of this rainfall. The rainfall probably not reaching the South Dorset coast until the early hours.

Elsewhere dry and starting clear, with cloudcover increasing from the west as we progress through the night. It will be a warm, muggy night everywhere.

Tomorrow's forecast map;

This has been a challenging forecast to produce to say the least. Unlike today, where I had high confidence in my forecast, I have low confidence in this forecast, but it's the best I can come up with I think.

The area in red is at risk of developing thundery showers from late morning onwards, perhaps merging into some potent thunderstorm cells in the afternoon, although by the time this happens it may well have moved out of our region. This includes Oxfordshire, North Hampshire and parts of Berkshire. FWIW, the East Midlands into Lincolnshire may well see a late afternoon MCS tomorrow.

The area in green might see some sort of squall line developing. This includes the Forest of Green, Gloucestershire and maybe north Bristol. During the afternoon there could be some weak CAPE developing along with surface heating this could help to produce some isolated thundery showers along a convergence line from SE Wales into the Cotswolds and Midlands. There could be some isolated heavy falls of rain, gusty winds and isolated thundery activity mixed in here.

The area in blue, which includes Cornwall and parts of Devon will see some moderate rainfall enter the region late afternoon into the evening. This again could have some isolated thundery activity mixed in with it, although as sunlight fades, I expect any thundery activity to also fade.

Elsewhere, it's going to be a mix of sunny spells, cloudcover and the odd scattered shower. Not all places will see the showers, many will stay dry. The east of the region should see temperatures into the mid 20c's with the west of the region into the low 20c's.

A challenging forecast to which I may update if necessary at 23:00.

[Rammie]

Right now in North Somerset, it is nothing but blue sky from horizon to horizon.

[gloucesterlad]

Thanks AWD - not too far off the mark methinks.

I have a beer festival to go to in the Forest of Dean tomorrow evening and an isolated thundery shower should cool things down nicely

As long as the beer isnt warm !

Cheers !

John

[Andy Bown]

I'm going to predict sharp/heavy showers inWiltshire/Dorset from high based AltCas developing into discrete CBs tomorrow morning as the initial front moves in.

[AWD]

Right, 23:00 update and the forecast is generally going to stay the same. See original post for this. All I will do though is widen all 3 areas to include a larger landmass. I've done this due to uncertainty as to where showers and potential storms will form;

The red area now include most of Hampshire, Berkshire, Oxfordshire and easternmost Wiltshire. The green area now includes all of Gloucestershire, northernmost Wiltshire and north Bristol. The blue area now include all of Devon, Cornwall and Southwestern most Somerset.

[Andy Bown]

Lightning near Wells and Crewkerne in the last hour from fast moving thundery showers. Unfortunately a lot of low cloud so structure isn't visible here. Much more active storms near the IOW moving NNE so possibilities for Hants/Berks.

[Zephyr]

Morning everyone just been woken by the Blitztung App with lightening around the area, heard a few distant rumbles also.. Raining pretty heavy at the moment.

[Freddie123]

Thunder here as well about 15 mins ago.

[Polar Bear]

Morning everyone just been woken by the Blitztung App with lightening around the area, heard a few distant rumbles also.. Raining pretty heavy at the moment.

Which blitzortung app you got? Mine doesn't have alarm settings?.... Radar tells me though a band is creeping up to Newbury.. Haven't heard any rumbles so it may just be a shower. Don't forget those raincoats peeps when you go to work. My friend has been caught out doing her horses in Wokingham this morn... Shorts n tee shirts n caught in a hefty shower ... Oh dear I did warn!

[lettice]

Some thunder here at 5:30am

A drizzle of rain at that time too

[Frosty1]

Morning all from a cloudy Arborfield. 17c here with light breeze. Rain just starting from grey overcast skies.

[Zephyr]

Which blitzortung app you got? Mine doesn't have alarm settings?.... Radar tells me though a band is creeping up to Newbury.. Haven't heard any rumbles so it may just be a shower. Don't forget those raincoats peeps when you go to work. My friend has been caught out doing her horses in Wokingham this morn... Shorts n tee shirts n caught in a hefty shower ... Oh dear I did warn!

 

I have version 1.1.1 (95) 

 

I messed around with the alarm settings in preferences and now it warns me I have heard a few others on here say it doesn't warn them also but not to sure how I did it.

 

All I did was change settings in preferences - (Alarm settings)

(Ticked alarm enabled)

(Background query period is set to 5min)

(Notification distance limit is set to 50 km/mi)

(signaling distance limit set to 25km/mi.)

 

Then alarm signal settings

(Alarm audio signal: set this to what you what your alarm to sound)

(Alarm vibration duration: mine is set to max but doesn't seem to work for me?) 

 

Sorry if this isn't much help. 

[smoggyjester]

Well nothing here in hampshire just grey skies all the action must be just to the east of us reading se thread