Thunderstorm/Convective Watch: Summer 2010

Hal1

Even if it does, heat is still needed for lift so the energy (cape) can be tapped into.

Su Campu

Several hundred J of CAPE and -2°C LI progged for 18Z Monday as a potent little upper low moves southeastwards from Iceland. Let's wait and see if she delivers...:rolleyes:

maquiladora

0Z is a bit of an upgrade. But a lot can change in a few days :

maquiladora

Shock horror, looks like this isn't going to come off as shown a couple of days ago.

Ah well..... :rolleyes:

BoardsRanger

Its a shame we dont get storms like this one over here....

http://www.boards.ie/vbulletin/showpost.php?p=67339896&postcount=2

BEASTERLY

By the looks of the GFS Owen Quigg has the best chance out of anybody of seeing any storms on Monday night.

Has naybody seen him post here lately , I miss is antics!!!!

delw

BEASTERLY wrote: »

By the looks of the GFS Owen Quigg has the best chance out of anybody of seeing any storms on Monday night.

Has naybody seen him post here lately , I miss is antics!!!!

think he still banned,but didnt he throw the soother out of pram&said he'll never post here again

Deep Easterly

maquiladora wrote: »

Shock horror, looks like this isn't going to come off as shown a couple of days ago.

Ah well..... :rolleyes:

The EMHI 12z HIRLAM run has some convection developing tomorrow over the northern half of the country esp during the afternoon into the evening.

cloud forecast for tomoorrow 5pm:




but given the set up I think it could bubble up anywhere to be honest, so maybe some hope of a rumble or two somewhere, sometime tomorrow.

Deep Easterly

This brief video of a storm in Hong Kong a couple of days ago was posted up on TWO by one of their resident storm chasers. Some great lightning shots!

Ok, it is not as good as the storms here at home but still worth a watch...:pac:

WolfeIRE

tornado in us (Saturday)

http://www.youtube.com/watch?v=Kx0BE_cv3zA

M.T. Cranium

I am currently thinking that the convective potential on Monday is slight but not zero, the good factors in play are rapid height and thickness reductions (meaning cold air aloft coming closer to the surface through the day), strong winds developing at 700-500 mbs, breaks in cloud cover upstream signalling potential for sunny intervals to enhance lift, and from my research, statistical enhancement of precip at new moon event (timed for 03z Tuesday) as well as a good "J-field" event signature.

The negative factors would be under-performance of Friday system despite recent geomagnetic storm, long-term ridge-building, small overall size of incoming disturbance, and some concerns about lack of thermal profile support.

All things considered, it will probably be an active if not outstanding day, and some people may see a thunderstorm. The most likely area would seem to be east Galway across to about Meath, and north of that zone most of the way to the north coast. With any luck, DE will be rewarded for his months of patience and see some active weather (but I seem to recall many reports of big storms in Galway in 2009?). My risk zone above does not imply a lack of activity further south, there's just more instability indicated in the north where the stronger winds aloft will set in.

Su Campu

A few sferics showing up along the Derry and Antrim coasts in the last few hours. Where's Owen when you need him!!



There is some enhanced convection at the tip of the backbent occlusion, underneath the upper cold low. Hopefully the occlusion will give a bit more action to more areas further south tomorrow as it makes its way southeastwards. Got nothing today, turned out to be a lovely evening with a sharp inversion visible in the few banks of StCu

Deep Easterly

UK met office total recorded strikes for the months June/July 2009/2010:

June: 2009/2010


July: 2009/2010



Without a doubt the year 2010 has been nothing short of despicable for the nation's weather watchers. Firstly a fridged yet stupendously boring winter, a severely inactive spring which was then followed by a sunless bollix of a summer.

How long more is this sludge to continue to be spewed upon us?

DOCARCH

Those maps are shocking!

Su Campu

Deep Easterly wrote: »

UK met office total recorded strikes for the months June/July 2009/2010:




Without a doubt the year 2010 has been nothing short of despicable for the nation's weather watchers. Firstly a fridged yet stupendously boring winter, a severely inactive spring which was then followed by a sunless bollix of a summer.

How long more is this sludge to continue to be spewed upon us?

Well if you can just last another week then things look like getting interesting. ECMWF and GFS are agreeing on a large upper trough near Greenland and Iceland becoming cut off and taking up residence near or over us, just like the current one in the North Sea. That would be sure to bring some of us at least something to show for this month.

ECMWF


GFS

Deep Easterly

Su Campu wrote: »

ECMWF and GFS are agreeing on a large upper trough near Greenland and Iceland becoming cut off and taking up residence near or over us.

Latest ensemble mean chart seems to agree (not that the ensemble mean is any more reliable than the standard deterministic run), that troughing will dig in towards us from the NW towards the middle of next week:



Will be interesting to monitor how this may progress closer the time.

Deep Easterly

Tonight's ecm continues to hint that troughs will move closer to Ireland during next week:

120hrs:



144hrs:



Sea temps around Ireland at their warmest this time of year (around 15c-17c), which should interact nicely with this polar trough should it bear down upon us as forecast.



Too far out to be anyway hopeful or certain yet though..

Trogdor

Looks like some fairly intense storms down over Italy at the moment

Hal1

If only it were to shift a few thousand miles to the nw, we might be in business :rolleyes:.

WolfeIRE

some strikes off nw and south coasts
http://www.blitzortung.org/Webpages/index.php?lang=en&subpage_3=3

Su Campu

WolfeIRE wrote: »

some strikes off nw and south coasts
http://www.blitzortung.org/Webpages/index.php?lang=en&subpage_3=3

I've been watching Blitzortung and the Icelandic site for the last week or more and they've been consistently giving strikes in that area, even though satellite images show no convection there, mostly StCu sheets. I think there's some error in the system somewhere.

Here's the current satellite....totally stable conditions in that area. Compare it to the UK. I think we need to be careful when calling strikes near our shores.

Su Campu

The low near Iceland that will make its way here late tomorrow is producing some lightning activity near its centre this evening as a burst of convection takes place along the occlusion in response to an upper vort max. Clout tops were around -40°C at 18Z.



It will be interesting to watch how this evolves as it moves southeastwards over the next 24hrs. It could give some thundery activity to the north and west tomorrow night....

Su Campu

ESTOFEX have a chance of thunderstorms for the northeastern half of Ireland tomorrow

Storm Forecast
Valid: Wed 18 Aug 2010 06:00 to Thu 19 Aug 2010 06:00 UTC
Issued: Tue 17 Aug 2010 21:12
Forecaster: KOROSEC


A level 1 was issued for central Ukraine, eastern Belarus, Baltic states and NW Russia mainly for large hail, strong winds, excessive convective rainfall and tornadoes.

A level 1 was issued for NE Marocco, northern Algeria, SW Mediterranean into extreme SE Spain mainly for large hail, strong winds and excessive convective rainfall.

A level 1 was issued for Denmark mainly for excessive (convective) rainfall.

SYNOPSIS

A large trough centered over north-western Europe remains quasi-stationary. Embedded in this trough, an elongated upper low from British Isles moves towards the North sea. A weak upper low over extreme SW Europe makes only slow progress towards NE where it is expected to merge with the main trough on Thursday.
At surface, a frontal system across eastern Europe pushes towards western Russia, where both cold and northwards advecting warm front are focus for convective activity. Another (strong) cold front enters NW Russia from the north and merges with the southern frontal system overnight to Thursday.

DISCUSSION

... central Ukraine, eastern Belarus, Baltic states and NW Russia ...

With the eastern side of the large trough extending towards NE Europe/NW Russia, surface front continues moving eastwards during the day. Strong surface heating ahead of it should release moderate/high instability within the moist airmass. Deep layer shear of around 15 m/s should support organized storms, numerous multicells and a couple of supercells can be expected. Storms will tend to cluster into MCS or two, especially over Ukraine later in the afternoon. A threat level 1 was also extented NW-wards towards the Baltic states given the expected convective activity with slower moving storms, providing threat for excessive rainfall, as well as a few large hail/strong wind events. It seems that high-end level 1 fits the best for our criteria, though especially Ukraine might require a level upgrade if the severity/coverage will be higher that is currently anticipated.

Another focus for organized severe storms is expected along the northwards advecting warm front which merges with the slowly southwards moving strong cold front across NW Russia, connected with the deep trough/low to its north. South of this trough, a strong mid-level jet streak will provide strongly sheared environment, which will be only partly overlaping with the instability along/just ahead of the surface front. However, it seems that MLCAPE of around 1000 J/kg, around 15-20 m/s of deep-layer shear and QG forcing will be sufficient for numerous severe storms to occur along the front. Those will bring threat for intense rainfalls, large hail and strong winds. Near 200 m^2/^2 of SREH3 and around 10 m/s of LL shear seems supportive for a couple of tornadoes as well.

... NE Marocco, northern Algeria, SW Mediterranean into extreme SE Spain ...

A rather strong mid-level jet ahead on the upper low and large scale ascent will again support widespread convective activity. Marginal to moderate instability will be available, while jet provides 20-25 m/s of deep layer shear. Organized storms with numerous multicells/clusters are expected, while a couple of supercells cannot be excluded either, easpecially over the southern part of the level 1 area. Training effect of the cells and high PWAT suggests that intense rainfall/flash flood threat is likely as well. The more isolated storms/strong clusters should bring large hail and strong wind gusts threat.

... Denmark and UK ...

Placed beneath the remnants of the upper low and stationary surface low near Denmark, while another deepening vortex approaches from the west, Denmark will be in the position for widespread rainfall event. Jet streak will be to the north/south of vorticity maxima placed here, so weak wind field should support slow moving cells/storms and therefore excessive rainfall/flooding threat. With only marginal instability in place, convective storms are limited, but will enhance flooding threat where they occur.

Across central UK where models show some signals for some hundreds of instability, shallow convective cells could occur. Cold mid-levels and rather weak wind field could support some funnel clouds given the steep LL lapse rates. Similar temperature gradient in the lowest levels could support a few funnel clouds around Denmark as well.

darkman2

Some healthy development occuring across the West and Midlands atm. Looks like heavy showers across the Northern half of the country in particular and some thunder and lightning is likely aswell later on.

WolfeIRE

intense shower over Lough Neagh in past 20 mins
http://www.sat24.com/region.aspx?type=last&time=201008181230&country=gb

owenc

darkman2 wrote: »

Some healthy development occuring across the West and Midlands atm. Looks like heavy showers across the Northern half of the country in particular and some thunder and lightning is likely aswell later on.

Yes i an't beleive the height of the cloud massive highest i've ever seen,theres going to be a big bang!

WolfeIRE

intense shower over galway


lightening strike off NW coast too
http://sproule.co.uk/weather/svlightning.html
http://www.meteox.com/h.aspx?r=&jaar=-3&soort=lightning

snowjon

Very dark skies out to the west at the moment. It looks like a very intense shower just over Lough Neagh at the moment - the showers seem to decay by the time they get here, but this one might reach Bangor intact!

snowjon

Thunderstorm reported at Aldergrove - heading this direction !!

hellboy99

Lightning here now.