Very Heavy Rain Saturday Night with Flash Flooding/Lightning storms

darkman2

Radar suggests severe downpours atm across alot of areas in the South. Once again I would advise getting sandbags ready if you are prone to flooding not because it will happen but because it might and you may well be sorry if you don't take that advice. Even if I am wrong then very well and everyone is happy (at my expense!) but still you really should do that just in case. Better safe then sorry.

Supercell

Rainfall rates here frequently going over 20mm/hr will definately be flooding in Wicklow tonight.

darkman2

Supercell wrote: »

Rainfall rates here frequently going over 20mm/hr will definately be flooding in Wicklow tonight.

Radar suggests it's going to get somewhat more vicious then that for you atm. Interestingly the system is further north atm then was expected. Id have put the action in the South midlands further south. Embedded storms are also likely particularly later. Strong wind gusts aswell at times.


I know we cannot see it at night but some "circulation" may occur as per the estofex forcast - take it easy if driving.

Redsunset

Im finding that radar on Met Eireann does NOT represent the current precip rate very well at all. uk metoffice seem to have it spot on.

http://www.metoffice.gov.uk/weather/uk/radar/index.html

Welsh Wizard

Had a couple of showers earlier on, raining heavy the last 30 mins.. bit of a breeze too... Made extra room in my water butt... Madness how much one can gather from such small shed roof.... Shame its not beer..!!
Greystones, ww

M.T. Cranium

At 0600h, from radar and various observations offshore and on land, I think the centre is moving along the expected track converging on southeast Ireland, currently it appears to be about 50 miles south of Waterford heading towards Wexford and later north Wales. As pressures fall rapidly all around the developing low, it may appear to be moving inland or further north but this is also happening out to sea closer to the centre.

As to the tornadic potential, unless they are talking about isolated storms that form this afternoon in the westerly flow, I think the main risk zone for tornadic gusts would be from about southeast Wales to London; winds in southeast Ireland are likely to back from south to east and then to north before going westerly, and this would probably just keep up a steady moderate rainfall. Totals there are certainly heading for the 30-45 mm range. I would not worry about tornadic cells forming over southeast Ireland close to the low centre. Thunderstorms would be "elevated" meaning a lot of cloud to cloud lightning potentially in Wexford and Wicklow, possibly further north and northwest, in the next few hours.

Going back to take another look ...

Mothman

35mm since midnight (manual gauge). 4 intense bursts with with rain in between. It has stopped for now.
My stream is high but not as high as in erarly September.

Pressure 9mb past 3 hours 20mb since midnight.

harsea8

I'm in Athlone and back garden is flooded worse than I've seen in the 5 years I've been living here...must have been some downpour as it was relatively dry here until at least 1am

Redsunset

harsea8 wrote: »

I'm in Athlone and back garden is flooded worse than I've seen in the 5 years I've been living here...must have been some downpour as it was relatively dry here until at least 1am

Oh yes,and as DM2 and i said at beginning of thread.

had a feeling this one would dump water.

nacho libre

I see there was also flooding in Sligo and Dongeal from last nights deluge. I thought the heaviest of the rain would be confined to the South and East.

JanuarySnowstor

I must have slepy thru it all then:rolleyes:
In all fairness twas nothing exceptional!

Deep Easterly

This map from Ogimet gives a fair idea of the rainfall distributation over the 24hr period up to noon today from the main synoptic stations:

paulhac

Hi Patrick, I think we're missing something here!:)

M.T. Cranium

To keep a record of the actual rainfall, I saved the 31 October amounts which we can then add to the 1 Nov amounts when they are reported tomorrow morning ... and of course these amounts (for Saturday) include the various scattered showers that fell ahead of the system rainfall. In fact any rainfall here north of Shannon to Oak Park is probably all from those scattered showers.


Ballyhaise ... 0.2 + 26.5 ........ 26.7
Belmullet ..... 3.2 + 15.8 ........... 19.0
Casement ... 12.8 + 18.5 ....... 31.3
Claremorris .. 4.6 + 18.0 ......... 22.6
Cork Airport ... 5.5 +16.4 ........21.9
Dublin Airport . 1.1 + 25.4 ....... 26.5
Gurteen ... 3.1 + 24.8 ....... 27.9
Finner Camp n/a
Johnstown Castle .. 4.7 + 25.0 ..... 29.7
Knock Airport .. 3.0 + 19.7 ...... 22.7
Mace Head .... 0.8 + 19.7 ...... 20.5
Malin Head .... 5.0 + 29.2 ...... 34.2
Mullingar ... 0.9 + 24.6 ...... 25.5
Oak Park ... 0.5 + 24.7 ..... 25.2
Roches Point ... 7.4 + 17.0 .... 24.4
Shannon Airport ... 2.1 + 22.1 ..... 24.2
Sherkin Island .. 7.3 + 21.6 .... 28.9
Valentia .... 5.6 + 38.8 ...... 44.4


So look for this to be updated on Monday with the storm totals for a two-day period.

(Sunday amounts except for Casement added at 0545h Monday, Casement added 1930h)

Deep Easterly

paulhac wrote: »

Hi Patrick, I think we're missing something here!:)

Have no idea what happened to that pic Paul Must have timed out or something. :mad:

Anyways, Last nights rain was heaviest in the Southwest (Valentia) and lightest in the Northwest (Belmullet). Surprisingly, both Malin Head and Ballyhaise in the north Midlands recieved almost 30mm of rain from that front while Cork Aiport and Roaches point only saw below 20mm. (based on 0000hrs to 0000hrs UTC time) That rainband was more complicated as it did not go with the NW/SE split that was originally thought. Heavier bursts were more localised and were not confined to the areas forecast to get them.

M.T. Cranium

Yes, I updated the two-day totals in my earlier post, but from watching the radar during the overnight phase of the storm, I felt that there might have been even more rain in Tralee and Killarney (roughly) where some very heavy looking echoes developed. Any news reports of flooding?

Redsunset

This morning sat image taken at 9am clearly shows saturdays now deepened low in the north sea.

Discodog

redsunset wrote: »

Im finding that radar on Met Eireann does NOT represent the current precip rate very well at all. uk metoffice seem to have it spot on.

http://www.metoffice.gov.uk/weather/uk/radar/index.html

Surely the UK met office are gathering data from the same radars at shannon & dublin therefore the images should be identical. Is it that the refresh rate is higher & therefore more current.

I am asking because I work outdoors & am forever checking met eireanns radar on my mobi !

octo

Discodog wrote: »

Surely the UK met office are gathering data from the same radars at shannon & dublin

Correct - Metoffice display Met Eireann's data but at a lower resolution. As I check it right now, Met Eireann's is most up to date.

Redsunset

well comparing the two radars now ,Meto have precip in irish sea between wexford and wales at a much greater precip rate.
During the heavy rain the other night i had torrential rain and met eireann radar was showing 0.5 mm and meto had it in red so theres seemed right at the time.

Discodog

Could it be that your area is at the outer edge of Dublin radar & closer to a UK radar. The accuracy diminishes with distance so the UK radar may be more accurate if it is closer. My biggest gripe is that the rain now has a NW movement near Galway & ME's radar zones have less range from that direction so less warning.

Also as we are towards the edge of the radar & close to the sea we can be drowning in heavy drizzle which doesn't always show on the radar. Having said that having the radar on a mobi is a very useful tool & does make people wonder how you knew that the rain was about to start or stop !

octo

redsunset wrote: »

well comparing the two radars now ,Meto have precip in irish sea between wexford and wales at a much greater precip rate.
During the heavy rain the other night i had torrential rain and met eireann radar was showing 0.5 mm and meto had it in red so theres seemed right at the time.

I guess it was picking that up from their radar in south wales. Your area may be better served by the UK radar alright.

Discodog

This illustrates my problem. I see this & because of the WNW element to the rain I think maybe I can do some work as I am near Galway.



Then this happens. Its almost like it appeared out of nowhere. In fact it only stopped raining here for about half an hour.

Deep Easterly

Going from personal observation alone, I think the UKMO radar tends to overdo rainfall intensity from frontal type events and underdoes intensity from more showery types. The freak shower we had here on Hallowe'en evening was shown to be just that on the Met Eireann radar, while the UKMO radar just showed a light blue, low intensity event.

Another example was the morning of the 30th. At one stage the UKMO had high intensity reds and whites directly over me yet there was only light rain falling here. At the same time the M.E radar just showed light rain falling here which was more correct. However, I suppose locality is a big factor in this as I am sure experiences are different right around the country.