Convective / Storm Discussion Thread - 31st May 2017 onwards

[Mapantz]

Beast mode on rain totals around Essex..

https://www.wunderground.com/personal-weather-station/dashboard?ID=IESSEXHA9

https://www.wunderground.com/personal-weather-station/dashboard?ID=IESSEXHA5

https://www.wunderground.com/personal-weather-station/dashboard?ID=ICHELMSF35

Dozens of stations with an inch+

[NorthYorksWeather]

14 minutes ago, Mapantz said:

Beast mode on rain totals around Essex..

https://www.wunderground.com/personal-weather-station/dashboard?ID=IESSEXHA9

https://www.wunderground.com/personal-weather-station/dashboard?ID=IESSEXHA5

https://www.wunderground.com/personal-weather-station/dashboard?ID=ICHELMSF35

Dozens of stations with an inch+

Jealous, had 1.6mm today. Hoping we get a good soaking on Monday.

[matt111]

46 minutes ago, vizzy2004 said:

Jealous, had 1.6mm today. Hoping we get a good soaking on Monday.

Jealous with 1.6mm? 0.0mm here. 

[Chris Lea-Alex]

7 hours ago, matt111 said:

Jealous with 1.6mm? 0.0mm here. 

8 hours ago, vizzy2004 said:

Jealous, had 1.6mm today. Hoping we get a good soaking on Monday.

Now now gentleman. Size isn't everything ; )

[Stuart]

will today be the day to see my 1st storms of the year been let down a few time this year so far 

[Summer Sun]

Storm Forecast
Valid: Sat 03 Jun 2017 06:00 to Sun 04 Jun 2017 06:00 UTC
Issued: Sat 03 Jun 2017 06:47
Forecaster: TASZAREK

A level 2 was issued for CNTRL Germany mainly for mainly for large hail, severe wind gusts and excessive precipitation.

A level 1 was issued for Germany, E France and Switzerland mainly for large hail, severe wind gusts and excessive precipitation.

A level 1 was issued for NE Spain and S France mainly for large hail, severe wind gusts and excessive precipitation.

A level 1 was issued for Balkans mainly for large hail, severe wind gusts and excessive precipitation.

SYNOPSIS

Two large troughs are placed over N Europe. One is slowly and eastwardly approaching British Isles while the second is located over NW Russia and moves westward. Jet streaks extends from Finland up to Ukraine and over British Isles, but mostly outside instability areas. A weakening ridge covers CNTRL and S Europe. A shallow mid-level cut-off is located over SW part of Balkan Peninsula. Widespread thunderstorm activity with severe weather potential is expected in the belt stretching from NE Spain trough E France up to Germany on the bordering area between ridge and trough over NW Europe. Shallow surface lows are expected to develop over Spain and N Germany and will be divided by a small ridge over SW France. Another cluster of weakly sheared thunderstorm activity with some potential of producing severe weather will be placed on the E flank of the cut-off over Balkan Peninsula.

DISCUSSION

...W Europe...

A broad area of rich boundary layer's moisture (mixing ratios ~ 10-11 g/kg) overspreads Germany, Benelux, France, N Italy, N Spain and W parts of Mediterranean. Along with diurnal heating and evapotranspiration, a solid ML CAPE up to 1000-1500 J/kg develops over Germany. Weaker instability (ML CAPE ~ 600-800 J/kg) is expected over France while a partially strongly capped ML CAPE up to 1000-1500 J/kg over Spain. Although CI over Spain is a bit uncertain, isolated cells which will get trough the cap may be capable of producing large hail (steep lapse rates 15 m/s DLS), microburst type severe wind gusts (enhanced delta theta-e values) and excessive precipitation (mainly in the NE Spain with enhanced PW values).

Better confidence for severe thunderstorm development is over Germany, mainly due to better lift (low developing in the afternoon hours lobes of PVA), and the coverage of unstable airmass. Due to weak CIN, a widespread convective development is expected around noon hours, mainly over S, CNTRL and W Germany. Thanks to around 15 m/s DLS, cells will be merging into multicell clusters, and a few local supercells (due to local wind field interactions with mountains) cannot be ruled out as well. Due to rather weak airflow (~ 8-10 m/s at 700 hPa) and high PW values (> 30mm) one of the main threat will cover excessive precipitation, especially within training multicell clusters. Large hail up to 3-4 cm is also possible if the supercell thunderstorms will be present. Although both mid-level airflow and delta theta-e values are not impressive, a few local severe wind gusts events are possible. Convective activity should drop in the late evening hours, except E Germany (passage of the shortwave trough) and NE Spain, where thunderstorms will be active until late nighttime hours. Superimposing stratiform and convective precipitation over W Alps (Switzerland, E France) may also cause excessive precipitation and a local flash flooding event.

...SE Europe...

A surface advection of a moist air from the Black Sea and moisture pooling due to evapotranspiration and strong diurnal heating develops rich moist boundary layer with mixing ratios ranging from 10 to 12 g/kg. Along with steep lapse rates (associated with an eastwardly moving cut-off placed over Albania) ML CAPE up to 2000-2500 J/kg is possible according to GFS, mainly over E Greece and Bulgaria. Rest of the 50% area covers ML CAPE up to 800-1000 J/kg. Majority of Balkans remain under very weak vertical wind shear (< 10 m/s DLS) which indicate isolated pulse thunderstorms locally clustering into multicells. Main risk covering these storms concerns excessive precipitation (rich in moisture vertical profile weak storm motion), and microburt type severe wind gusts (enhanced delta theta-e values). Given locally strong CAPE with steep lapse rates, a 2-4cm large hail event cannot be ruled out, mainly over Bulgaria, E Greece and partially W Turkey. Convection should weaken in the late evening hours, but it will be ongoing during nighttime over Aegean Sea and W Turkey.

http://www.estofex.org/

Edited June 3, 2017 by Summer Sun

[Summer Sun]

Good effort in the SLGT zone

 

[Mokidugway]

Lots of bubbleupacus in Manchester this morning ,quite crisp too 

[Martin Auld]

some great convection this morning

[Frosty hollows]

2 hours ago, Summer Sun said:

Storm Forecast
Valid: Sat 03 Jun 2017 06:00 to Sun 04 Jun 2017 06:00 UTC
Issued: Sat 03 Jun 2017 06:47
Forecaster: TASZAREK

A level 2 was issued for CNTRL Germany mainly for mainly for large hail, severe wind gusts and excessive precipitation.

A level 1 was issued for Germany, E France and Switzerland mainly for large hail, severe wind gusts and excessive precipitation.

A level 1 was issued for NE Spain and S France mainly for large hail, severe wind gusts and excessive precipitation.

A level 1 was issued for Balkans mainly for large hail, severe wind gusts and excessive precipitation.

SYNOPSIS

Two large troughs are placed over N Europe. One is slowly and eastwardly approaching British Isles while the second is located over NW Russia and moves westward. Jet streaks extends from Finland up to Ukraine and over British Isles, but mostly outside instability areas. A weakening ridge covers CNTRL and S Europe. A shallow mid-level cut-off is located over SW part of Balkan Peninsula. Widespread thunderstorm activity with severe weather potential is expected in the belt stretching from NE Spain trough E France up to Germany on the bordering area between ridge and trough over NW Europe. Shallow surface lows are expected to develop over Spain and N Germany and will be divided by a small ridge over SW France. Another cluster of weakly sheared thunderstorm activity with some potential of producing severe weather will be placed on the E flank of the cut-off over Balkan Peninsula.

DISCUSSION

...W Europe...

A broad area of rich boundary layer's moisture (mixing ratios ~ 10-11 g/kg) overspreads Germany, Benelux, France, N Italy, N Spain and W parts of Mediterranean. Along with diurnal heating and evapotranspiration, a solid ML CAPE up to 1000-1500 J/kg develops over Germany. Weaker instability (ML CAPE ~ 600-800 J/kg) is expected over France while a partially strongly capped ML CAPE up to 1000-1500 J/kg over Spain. Although CI over Spain is a bit uncertain, isolated cells which will get trough the cap may be capable of producing large hail (steep lapse rates 15 m/s DLS), microburst type severe wind gusts (enhanced delta theta-e values) and excessive precipitation (mainly in the NE Spain with enhanced PW values).

Better confidence for severe thunderstorm development is over Germany, mainly due to better lift (low developing in the afternoon hours lobes of PVA), and the coverage of unstable airmass. Due to weak CIN, a widespread convective development is expected around noon hours, mainly over S, CNTRL and W Germany. Thanks to around 15 m/s DLS, cells will be merging into multicell clusters, and a few local supercells (due to local wind field interactions with mountains) cannot be ruled out as well. Due to rather weak airflow (~ 8-10 m/s at 700 hPa) and high PW values (> 30mm) one of the main threat will cover excessive precipitation, especially within training multicell clusters. Large hail up to 3-4 cm is also possible if the supercell thunderstorms will be present. Although both mid-level airflow and delta theta-e values are not impressive, a few local severe wind gusts events are possible. Convective activity should drop in the late evening hours, except E Germany (passage of the shortwave trough) and NE Spain, where thunderstorms will be active until late nighttime hours. Superimposing stratiform and convective precipitation over W Alps (Switzerland, E France) may also cause excessive precipitation and a local flash flooding event.

...SE Europe...

A surface advection of a moist air from the Black Sea and moisture pooling due to evapotranspiration and strong diurnal heating develops rich moist boundary layer with mixing ratios ranging from 10 to 12 g/kg. Along with steep lapse rates (associated with an eastwardly moving cut-off placed over Albania) ML CAPE up to 2000-2500 J/kg is possible according to GFS, mainly over E Greece and Bulgaria. Rest of the 50% area covers ML CAPE up to 800-1000 J/kg. Majority of Balkans remain under very weak vertical wind shear (< 10 m/s DLS) which indicate isolated pulse thunderstorms locally clustering into multicells. Main risk covering these storms concerns excessive precipitation (rich in moisture vertical profile weak storm motion), and microburt type severe wind gusts (enhanced delta theta-e values). Given locally strong CAPE with steep lapse rates, a 2-4cm large hail event cannot be ruled out, mainly over Bulgaria, E Greece and partially W Turkey. Convection should weaken in the late evening hours, but it will be ongoing during nighttime over Aegean Sea and W Turkey.

http://www.estofex.org/

Wish I was in Barcelona THIS weekend!

[NUT]

Got a few showers here that have broke out almost from nothing. Hopefully a lively afternoon (although won't top last saturday)

[NUT]

And just had a flash and a grumble

[Flash bang flash bang etc]

Waiting patiently for next week when we might see something good

[GrangemouthBairn]

Thunderstorm in Glasgow at the moment

[Ross B]

5 minutes ago, GrangemouthBairn said:

Thunderstorm in Glasgow at the moment

A decent one here in the south side with hail and frequent thunder and lightning.  Radar looks good to the south west with more showers developing. 

Edited June 3, 2017 by Ross B

[Ross B]

More thunder from the next cell, in a good spot today for once 

[NUT]

Stonking afternoon here! Second thunderstorm went through more maybe on the horizon

[Robbie Garrett]

Quote

 

Forecast Summary

Outlook for the UK over the next 6-30 days

UK Outlook for Thursday 8 Jun 2017 to Saturday 17 Jun 2017:

Thursday and Friday will be mostly cloudy, with showers or longer spells of rain spreading in from the southwest. The rain could be occasionally heavy, particularly in the south, with an increased risk of thundery downpours here, but it will become brighter in the west later. Temperatures will widely be above average, with hot, humid weather possible in the south and southeast where it may feel humid. Unsettled weather is likely to continue as we head into the weekend and beyond, with further spells of rain or scattered showers. These will tend to be most frequent in the west and it may be very windy here too, with the risk of gales in places. Temperatures will continue to be above average, perhaps becoming very warm at times.

UK Outlook for Sunday 18 Jun 2017 to Sunday 2 Jul 2017:

For mid June, confidence is very low, however the most likely scenario is for more spells of wet and windy weather in the northwest, with somewhat more settled and warmer conditions further south and east. There is the possibility of some heavy and thundery showers at times though, particularly in the southeast. Temperatures are most likely to be above average, and perhaps very warm or hot at times in the south, but there is the possibility that the temperatures may begin to trend down later in the period.

Updated: 01:20 on Sat 3 Jun 2017 BST

 

Sounds good

[Windblade]

19 hours ago, Frosty hollows said:

Amazing photos!Thanks for sharing

My pleasure. I count myself extremely lucky to have been in the right place at the right time. Been trying to capture a uk funnel cloud or tornado for over a decade. Who would've thought I'd get that shot right near home?

I went out yesterday evening and managed to get some lovely shots of a decaying inactive mcs set against the setting sun just to the west of Eltham. I'll upload them when I get a chance. I thought this year wasn't going to be great for storms for me (and I must admit I can get a bit grumpy sometimes without my storm fix, apologies) but so far I've witnessed four smallish ones now, a big one and a funnel cloud, and we're only in June! I'm really pleased how things have gone so far now and releaved it hasn't been a repeat of a dismal 2016. I really do wish everyone else here in other spots the best of luck.

Yesterday it was the south east's turn. Today it's the only place not to have a storm risk (but feels lovely and fresh with a cool breeze so after the recent humid/sticky heat we've had all week I'll happily take that) so good luck everyone and happy hunting. 

Edited June 3, 2017 by Windblade

[NUT]

Think the showers have finally cleared through here but a lot of thunder pretty much from before 12 onwards

[Martin Auld]

Even with the increased activity in Scotland today I'm still in the no storms club.... sigh, when will I escape

[Dangerous55019]

Just looked up from the barbecue, and it looks like we've got some exceptionally weak convectivity going on around here this evening. 

[Chris.R]

 Lots of insolation going on today so as a result a few heavy showers late afternoon. Reached 19.7°C, quite respectable with an on-shore wind. 

[Weather-history]

 

[Mokidugway]

3 hours ago, Chris.R said:

 Lots of insolation going on today so as a result a few heavy showers late afternoon. Reached 19.7°C, quite respectable with an on-shore wind. 

Rather pleasant in Manchester City centre 21.5c a grand day ..