Heavy Rain Risk Sunday Night/Monday

hellboy99

87.5mm of rain here in 24 hours and my garden will vouch for that.

fishmahboi

http://www.tv3.ie/weather.php?defaultLocation=Arklow

Check out tomarrows rainfall forecast on this link, it looks like the southwest and themidlands are gonna get tons of rain

Min

I needed rain as my land was dried out and the grass growth was being affected.

I had troughs out in fields that I give some meal to some calves, they were all full to the brim with water and an empty barrel must have had near 4 inches or so of water in it.
It was unreal.

My well that I get my water from was low, I went upto it today and expected to hear one of the springs flowing into it - two springs supply the well but one was gone dry, heard nothing, looked down the narrow hole and I could see the water was at the top of the well.

I think we must have got something similar to Danno. It is in the general area.

Would upland areas get more rainfall than lower elevations?

M.T. Cranium

Usually the heaviest rainfalls are found about half-way up slopes facing the oncoming moisture-laden clouds in any given climatic zone. I'm sure this would generally be true in Ireland but when you have convection of course the maximum will be wherever the convective clouds travel, if they happen to go upslope they will dump more of their load there too. Depends on how big a barrier the hills or mountains form, here on the west coast of Canada they form a very large barrier to the point of taking all the rain from some systems, and there are places about halfway to summit levels on the coast here that get 3-5 times as much rain as we get in the flat plain that the city is built on. In Ireland the mountains are not that high so I would imagine you might find 30-50 per cent increases in regional rainfall long-term at some locations that face south, east or west (north rarely being a direction for moisture-laden air to arrive). Perhaps someone knows of a station that illustrates this, but I'm sure it would be the case. Then there are of course rainshadow effects in given wind directions, because the extra rain that falls on the mountains is no longer available to fall downstream in the air flow. I gather that Dublin and Casement were in somewhat of a rainshadow for most of this past event, getting less rain than Ballyhaise or other places not being shielded from the SSE by the Dublin-Wicklow mountains.

Where I live, we get a rainshadow from the Olympic Mountains in northwest Washington state, but this is much more of a factor in Victoria, BC where they only get half the annual rain that most of the Vancouver area gets. It can rain heavily there too but the wind has to come in from either the southeast or the west to avoid the big rainshadow effect.

pauldry

Today is the first day I heard about the rainshadow phenomenon thingy MT(excuse spelling)

Sligo gets it in the North wind I think as Benny Bulby blocks bursts of belts of rain:)

Danno

Min, I was looking at the radar returns on NetWeather premium... this one at 3.45am caught my eye...

http://live.laoisweather.com/images/sep2010/0345.png

I think places like Castlecomer got more than here. There is a station in Coan village, SE of Castlecomer that would make interesting reading.

fishmahboi

Danno wrote: »

Min, I was looking at the radar returns on NetWeather premium... this one at 3.45am caught my eye...

http://live.laoisweather.com/images/sep2010/0345.png

I think places like Castlecomer got more than here. There is a station in Coan village, SE of Castlecomer that would make interesting reading.

I don't mean to sound like an idiot but was that yestardays rainfall radar or is that todays?

M.T. Cranium

I think it was captured about 24h ago now ... if you look at the met.ie radar feature now and animate it, you can see the swirl of the upper level low right about over Mullingar, with moderate rain bands wrapping around that now from the northwest. This feature will only drift a bit further east before daylight returns, then the whole air mass to the south which is fairly quiet at this point will become unstable with the daytime heating. But some rather heavy rain could develop overnight around the upper low in central and northwest counties.

Danno

The radar return was from 3.45am Monday Morning... almost 24 hours ago now.

fishmahboi

Ok thanks

Redsunset

Had mad rain all day.the front really did come to life again in the east,
Just to add that rainfall totals by the models were not so crazy after all.

thetonynator

Had very heavy rainfall from approx 9p.m. Sunday until 5p.m. Monday, stopped for an hour or so n the morning. Dont have any way of measuring it, but it wasn't light rain or mist at any point, it was heavy rain all the time!!!


River Nore has gone from its lowest level in years to a full flood.

Deep Easterly

redsunset wrote: »

Just to add that rainfall totals by the models were not so crazy after all.

Yep, I guess they were onto something alright. The NAE model, which I don't normally have much time for as it tends to overdo rainfall intensity, did surprisingly well I think - not only in terms of actual accumulations, but where the highest accumulations would occur.

A further 16.0mm here since midnight and still raining, albeit much lighter. A very morose and doleful morning.


Met rainfall radar sequence for the period 1.00am 6th Sept to 12.00am the 7th Sept, which proved to be one of the wettest days over much of Ireland for quite a while:

https://www.youtube.com/watch?v=Br-S2g2zhsk

What I find interesting is how the slackening 500hpa gradient affects the speed of the actual showers that developed in the SW relative to the speed of the frontal zone as the upper low moved in over the west during the afternoon!

Discodog

yr.no have got today so wrong !. Its hammering down here with thundery showers that appear to be travelling in circles so no escape !.

Chicken Run

so
rain gauges
can I make one at home ??
I'm bored and can't work cos it's raining...
Normally gauge the amount of rain by what's in the horse's empty feed bucket but it tipped over in the wind.

Su Campu

Sligo airport has just had heavy rain. They issued 3 METARs in 4 minutes, with visibility (in metres) and cloud base lowering rapidly each time.

http://www.dawn-it.com/met/

2010-09-07 10:00:00 METAR EISG 071000Z AUTO 20004KT 150V240 7000 -RA FEW004 BKN012 OVC026 13/12 Q0991 RERA=
2010-09-07 09:42:00 SPECI EISG 070942Z AUTO VRB03KT 3900 +RA FEW005 BKN010 OVC017 13/12 Q0991=
2010-09-07 09:39:00 SPECI EISG 070939Z AUTO VRB03KT 4000 +RA FEW005 BKN015 OVC020 13/12 Q0991=
2010-09-07 09:38:00 SPECI EISG 070938Z AUTO VRB03KT 4200 +RA SCT010 OVC017 13/12 Q0991=
2010-09-07 09:30:00 METAR EISG 070930Z AUTO 17005KT 150V210 5000 RA BKN014 OVC020 13/12 Q0992

Min

Danno wrote: »

Min, I was looking at the radar returns on NetWeather premium... this one at 3.45am caught my eye...

http://live.laoisweather.com/images/sep2010/0345.png

I think places like Castlecomer got more than here. There is a station in Coan village, SE of Castlecomer that would make interesting reading.

Yeah that was heavy rain on Sunday night as the radar confirms, not to mention the rest that fell, it was exceptional.

I live a few miles from Coon as the crow flies, I only saw the rain records for there twice - one last year on Met Eireann's summer report and another on the major thunderstorm event of 1985.
It would be interesting indeed if there was access to that information.

Danno

Min wrote: »

It would be interesting indeed if there was access to that information.

I have a feeling that information will surface fairly shortly...

mickger844posts

Discodog wrote: »

yr.no have got today so wrong !. Its hammering down here with thundery showers that appear to be travelling in circles so no escape !.

I have lost all faith in Yr.no as their forecasts over the last number of weeks especially with regards to rain and totals have been way out. I can't rely on them anymore.

sliabh beagh

my 24 hr total maxed out at 54.9mm from 8pm sunday til 8pm monday(6/9/10)

Danno

The story [so far]...

Rain begins at 9pm Sunday night...
by 3.26am a rate of 57.8mm/hr is recorded
by 10am a total of 83.3mm has been recorded.
by 4pm Monday another 32.1mm is added
by 7pm Monday the rain mostly light but another 3.5mm is added
by 9pm Monday a few showers add a further 2.2mm to bring the 24 hour total to 121.1mm
At 9am Tuesday another reading is made. Only 1.1mm fell overnight bringing the 36 hour total to 122.2mm
Tonight, 9pm Tuesday the 48hr total is 122.7mm as 0.5mm was recorded from showers during the day.

Looking at the radar, a big clump of thundery showers are pushing in from the west.

M.T. Cranium

Danno, that was fortunate that your area missed out on heavier showers today. What's the local situation on flooding?

The activity over western Galway and Mayo looks intense and as SC noted there are signs of convective development, it's almost like a meso-scale convective complex although it's a bit cool for that. I could imagine there being 20-30 mm per hour rainfalls in that, not over any reporting stations at this time, wondering if Nacho Libre is near or in that area? Anyone else on hand to give us a reading on conditions? It seems to have kept a bit of distance from Galway and where I imagine DE lives, but could be seeing lightning from it perhaps. Those Connemara lakes are going to overflow at this rate.

Storm 10

Nothing to report in Galway City yet but that rain looks like it will hit at some stage will keep you posted.

Oscar Bravo

Very heavy rain in Castlebar at the moment.no thunder or lightening to report though.

Lumi

M.T. Cranium wrote: »

It seems to have kept a bit of distance from Galway and where I imagine DE lives, but could be seeing lightning from it perhaps. Those Connemara lakes are going to overflow at this rate.

Dry and breezy in Galway and likely to stay that way judging by the latest radar. I suspect that it's the same story in Tuam. Pity - I was looking forward to a reprieve of Sunday nights extravaganza. Looks like Nacho's having all the fun tonight!

Su Campu

There are some stations on the IWN in that area MT. Ballycroy is up to 71mm for today, and Westport 40mm

MayoForSam

Just after driving back from Castlebar to Tuam, some of the most intense rain I've ever driven in, my wipers could not keep up.

Danno

M.T. Cranium wrote: »

Danno, that was fortunate that your area missed out on heavier showers today. What's the local situation on flooding?

No major flooding around here. The River Nore, Irelands fastest flowing river is less than one mile away from here so it takes the load away smartly. I have photos on this thread here... http://www.irelandsweather.com/forum/general-weather-discussion/heavy-rain-sunday-and-monday/60/

...if you go to page 9 on that thread you will see more photos from Omagh, County Tyrone, Northern Ireland. RTE TV News tonight showed footage from flooding in Athlone in Westmeath County and Mountmellick in Laois County. See here... http://www.rte.ie/news/2010/0907/6news_av.html?2815124,null,230

sunbabe08

there was a nice storm that passed over galway and mayo. lucky them:)

fishmahboi

sunbabe08 wrote: »

there was a nice storm that passed over galway and mayo. lucky them:)

Judging from the radar and from forecasts outside of met eireann it looks like the southwest will get heavy thundery showers that gradually weaken as they approach the east