The driest place in Ireland?

Supercell

Was in Terenure earlier and the sun was splitting the stones and the car thermometer was reading 19.5°C was very pleasant indeed, yet its dull and overcast here and seems to be most other places too today around the country.

Have noticed this many times, there seems to be an area from Dalkey to Sandymount on the coast and out to Rathmines/Rathgar /Terenure that really catches the rain shadow when conditions are right and is sunny when most other places are dull.

Interestingly this area has had some of the most violent thunderstorms too - think of Stillorgan , Lepardstown and Mount Merrion in recent years, indeed Ireland's heaviest daily total came during a prolonged thunderstorm in Mount Merrion 11 June 1963.

I'd surmise that this rain shadow effect allows temperatures to soar in pretty moist air when conditions are right causing massive thunderstorms occasionally.

I seem to recall reading somewhere that Dalkey is the driest place in Ireland (anyone know if that's true?). I'd bet, sticking out into the sea, that Dalkey is one of the wettest too during a northeasterly for the same reason its the driest overall (prevailing wind being a southwesterly).
Anyone care to speculate or am I talking nonsense here (wouldn't be the first time!!)?

highdef

I read somewhere (can't remember where right now) that the area around Sutton through Baldoyle and up to around Portmarnock is the driest part of Dublin, and indeed Ireland. I'm from Baldoyle and would well believe it. There have been many times where I have been driving home from the city along the coast road and it may be raining or at least wet and once I get close to the turnoff near Sutton, it dries up dramatically. Obviously this does not happen all the time but it has happened a good few times. Also has happened a good few times if driving from Donaghmede to Baldoyle - Wet ground until about the Donaghmede roundabout and then dry or almost dry from there on.

Mobhi1

Was in the city centre today and it was also quite sunny and warm though with a very strong southerly wind.
When I came home I noticed I'd measured a max of 19.5 in the back garden.

mike65

Yeah I think North Co Dublin is the driest spot on average.

Mike.

Supercell

Aha!!, I've been researching this and just remembered I have a copy of "The climate of Dublin" (published in 1983).

I just dug it out and here's an excerpt (seems Dalkey might be the driest but officially probably Ringsend is) :-

Of the stations listed in table XXVII, the driest station was Dalkey (Torca Hill) with an estimated annual average of 662mm. Th driest station for which rainfall records were available over the complete 30-year period was Ringsend with an annual average of 680mm

Its a statistic jammed book and would recommend anyone with an interest in Dublin weather to buy - you can get it I think in the Government publications shop beside the passport office in town (if its still in print).

If anyone is interested I could scan in table XXVII which lists rainfall totals per month for stations all over Dublin?

So I guess Ringsend people can proudly claim to live in Ireland's Algarve!!(though Dalkeyites could claim a stake in the title too!).

Supercell

For anyone thats intrested here's the rainfall stats for around our capital, might be of interest to Dubliners.
Global warming has happened since then, maybe these averages are a bit different now, but the places havent moved, I suspect its a little wetter now than then.
The snow stats are interesting and certainly have changed, maybe I'll post them later this year when we enter the snow season proper.
The charts way look a bit wonky but thats the way they are printed , it seems printing tech in Ireland in 1983 was pretty basic

Mothman

I have the 61-90 stats. The 80s must have been a dry decade and the figures are lower than the 51-80 data.

No mention of Dalkey, so I've no idea how how the annual figure has been estimated for there. Also i'd be surprised that a site 96m high would be so dry, just like i'm surprised that 2 sites on Howth, one at 6m the other at 122m have the same annual total. I assume the higher site is on the NE side, and the Dalkey site is probably a similar aspect. Both the Howth sites have closed. Howth Castle is not mentioned in my dataset.

Ringsend is the driest with 666mm
DUBLIN (UPR.O'CONNELL ST.) 682
HOWTH (DANESFORT) 685
HOWTH (D.C.) 688
DUBLIN (CLONTARF) 691
DUBLIN (MERRION SQUARE) 695
MALAHIDE CASTLE 698
DUBLIN (GLASNEVIN) 704

Outside Co. Dublin, next driest is
Co. Louth
ARDEE (ST.BRIGID'S HOSP.) 744

Co. Kildare
Kilkerry 745
Athy 746
Celbridge 747

Co. Meath
Co. JULIANSTOWN G.S. 750

My max yesterday was 18.7C, would have got near 20C with more sunshine.

mike65

Basicly stay away from high ground is the message!

Mike.

Supercell

Mothman wrote: »

No mention of Dalkey, so I've no idea how how the annual figure has been estimated for there. Also i'd be surprised that a site 96m high would be so dry, just like i'm surprised that 2 sites on Howth, one at 6m the other at 122m have the same annual total.

Thanks for the updated figures Mothman, very interesting.

I wonder if the fact that both Howth and Dalkey stick out into the sea a bit and rise very rapidly to a peak but don't geographically have much area at high height therefore orographic lift effects are less than the height might otherwise suggest.

Both our figures agree that Ringsend is probably the driest area in Dublin and therefore the country too in all likelihood.
I wonder if it's cold enough, does Ringsend also have the greatest snowfall in a NE wind too?

Must drive up there next weekend and have a look at the lay of the land and try to figure out why that is.

Snowbie

Can see the Ben of Howth from my house and it is always shrouded in cloud in a moist southerly wind.Orographic lift does take place there but is minimal compared to the mountains.I wouldnt expect this type of lift can sustain appreciable rainfal totals up there but it is worth mentioning that in any easterly event when possible, snow can arise on the deer park side of Howth being sheltered by the wind by the Ben ,can have decent snow fall and is clearly visible from here and High Def can back me up on that.

Have travelled up there several times and the extreme of temps all around the headland is really astounding.In the set up above the deerpark golf course or sometimes we call it here the graveyard side was 3c colder than howth hill side which is exposed to the easterly.With height and shelter the colder side gives a nice pic in winter of snow on the golf course while it is wet or damp here.

patneve2

Very interesting thread. I wouldn't be surprised if Dalkey were the driest place in Dublin...Living here at the moment and there definitely is a rain shadow when bands of rain come from the South West, West or North West...happening right now (see attached image, this has happened countless times!!)...
Regarding easterlies, when the flow off the sea is strong, precipitation amounts are surprisingly small in Dalkey, however when the flow is slack (19th to 23rd December 2010) snow accumulations are quite high! There definitely was some orographic lift from Dalkey hill last December (even though its barely 100m high!), I remember showers stalling over Dalkey and then weakening considerably as they made it past the hill...

octo