Percentage of the time it rains in Ireland

Odelay

So I have employed several people from outside Ireland and I’m trying to convince them it is feasible to cycle the 5km to work. However I keep getting hit with the old it’s always raining in Ireland.

I have searched and can find plenty of information on rainfall, average volumes of rain etc, but nothing on the percentage of time it is actually raining. Does it rain for 5% of the time or 50%? There must be some information on this but I can’t find it.

Anyone have any ideas?

Calibos

Where in Ireland? You'd get massively different answers depending on where. Eg Could be 1% of the time in Dublin/Wicklow but 80% of the time in Galway or Donegal for example. Pulled the numbers out of my ar5e but avg annual rainfall on the east coast is much much lower than the west coast.

Odelay

Calibos wrote: »

Where in Ireland? You'd get massively different answers depending on where. Eg Could be 1% of the time in Dublin/Wicklow but 80% of the time in Galway or Donegal for example. Pulled the numbers out of my ar5e but avg annual rainfall on the east coast is much much lower than the west coast.

Cork/Waterford.

Atlantic Dawn

I'd say for the actual journey to and from work in that window it would be about 5%.

BailMeOut

5km cycle is maybe 30 mins so you are only talking 1/24th of the day that you are worried about rain so you'd be quite surprised how few times you get wet cycling to or from work. Anyway as they say there is no such thing as bad weather if you have the correct clothing.

ectoraige

Odelay wrote: »

So I have employed several people from outside Ireland and I’m trying to convince them it is feasible to cycle the 5km to work. However I keep getting hit with the old it’s always raining in Ireland.

I have searched and can find plenty of information on rainfall, average volumes of rain etc, but nothing on the percentage of time it is actually raining. Does it rain for 5% of the time or 50%? There must be some information on this but I can’t find it.

Anyone have any ideas?

I can only give my own anecdote, but I've cycled 3km in and out of work most days for the last seven years and it really surprised me how uncommonly I have to use rain gear. Yes, I have it in my bag for when I need it, but it's really only maybe once a fortnight that I use it in winter, even less come summer.

I'm sure you're aware of the cycle to work scheme, another thing employers can do to help make their workplace cycling friendly is to provide proper secure bike parking.

Teepinaw

I don't know the answer to your question, but does this help any bit?

https://irishcycle.com/2016/11/15/2-of-7-excuses-why-ireland-cant-copy-cycling-in-the-netherlands/

M.T. Cranium

Here's a link to the 1981-2010 "normal" values for Cork.

https://www.met.ie/climate-ireland/1981-2010/cork.html

In that, you will find line entries giving the number of days that record small, medium and medium-large amounts of rainfall. You could assume the first set would not affect cyclists much at all, so would say the second and third lines tell the story on percentage of time it might rain, I would say for a month where there are entries of 8 and 4 days in those, you could say 25% of hours for the 8 days and 50% for the 4 days. Both of those add up to 2 days, so a total of 4 days out of 30 or 31.

So in summary, the answer is probably around 10 to 15 per cent chance of significant rain falling in any given hour. That would be in the wetter months (October to April basically) so probably 5 to 10 per cent chance in the late spring and summer.

Of course I don't have to tell you rainfall can be feast or famine, some months are going to be a lot wetter than average and some a lot drier so those are only long-term averages. You could get a soaker several times in a week in a bad spell and you could go two or three weeks without seeing any rain at all.

Day Lewin

Dublin is the driest, by a long margin. Luckily for the capital!

Whereas if your friend was wondering about life in County Mayo, er.....Rains all the time.
In Galway, 2 days out of 3, I'm not joking.

But Leinster is grand.

pauldry

it actually doesnt rain ALL the time in the West.

I have done nearly 100 parkruns in Sligo and I would say it rained at 10 of them.

So 10 to 15% tops here

5% or less in Dublin

snowstreams

You could look at the number of wet days for each location.

Sydney and New york are wetter than Cork or Galway but they have roughly the same number of wet days as Dublin.
The rain falls faster there in a shorter space of time.

Id prefer it that way, rather than getting drizzle.

Jpmarn

I think you’re more likely be caught out in rain in Singapore than in Ireland. Covered footpaths and bus shelters are very common there. It also provide shade from the strong sunshine as it is almost on the Equator.

Odelay

snowstreams wrote: »

You could look at the number of wet days for each location.

Sydney and New york are wetter than Cork or Galway but they have roughly the same number of wet days as Dublin.
The rain falls faster there in a shorter space of time.

Id prefer it that way, rather than getting drizzle.

Thanks for the input everyone.

Snow streams, do you have a link for your information?

is_that_so

From Wikipedia.

The average number of "wet days" (days with more than 1 mm (0.039 in) of rain) ranges from about 151 days a year along the east and southeast coasts, to about 225 days a year in parts of the west.

beauf

I think when you are driving or on public transport you think it rains more than it does.

I was surprised how little rain effected me when cycling.
Usually it was much faster on a bike than car, bus on a rain day as traffic was worse and on the bike it made no difference.

I would more put off by wind. My route was very open to wind though.

vrusinov

Just getting number of rainy days is misleading, as there is a plenty of quite rainy days where it's possible to cycle for 5km without getting wet. It's often possible to wait 15 minutes to avoid the rain.

pauldry

And other quite showery days where it appears to be raining non stop but if you count the number of minutes its actually rained it might add up to 2 hours of the day.

Most prolonged rain lasts 4 to 6 hours and occur about 20 to 40 times a year . The other hours are mainly dry

March was an extremely wet month in the North West when there was 25 "wet days" as you say.

However well over 60 per cent of the duration of the month was dry so Wet "days" is far too misleading IMO

tuxy

BTW 5 KM is going to take about 15 mins even in Dublin with all the traffic and red lights.
5 KM is walking distance but the bike is an option if you want to speed things up.

benji2006

Here is a good article I saw a few years ago - seems credible based on personal experience...


How wet is a cycling commute in Ireland? Pretty dry!… if you don’t live in Galway.

https://www.shanelynn.ie/wet-rainy-cyling-commute-in-ireland-with-wunderground-and-python/

snowstreams

Odelay, if you look at the climate section on wikipedia for each city you can see the breakdown of weather data.

Rain fall and wet days is listed there too.

https://en.wikipedia.org/wiki/Cork_(city)#Climate

snowstreams

benji2006 wrote: »

Here is a good article I saw a few years ago - seems credible based on personal experience...


How wet is a cycling commute in Ireland? Pretty dry!… if you don’t live in Galway.

https://www.shanelynn.ie/wet-rainy-cyling-commute-in-ireland-with-wunderground-and-python/

Thats some strange statistics there for Galway.
I moved to Galway in 2008 and I got wet more often cycling in dublin than in Galway at first.
Though I think 2007-2008 were very wet years in Dublin.

To me it seems to rain here maybe 50% more often but nothing like triple!

EDIT:
Ok I see they are using 2015 as an example.
That was a terrible summer in Galway. So not a good example to use.

Riskymove

my own experience, which I have used as an example before, is that I played football every Tuesday and Thursday 7-8pm for about 15 years

I reckon I got really lashed on about 20 times, it snowed about 5 times etc

pauldry

Read that Galway article too. They must be using Mace Head.

The past 18 months has been pretty dry though as for all my sons outdoor training on Saturday mornings in April to June last year and April this year there was one shower of rain...in total and for the runs ive done its rained a lot more in the evening than mornings

I cycled to work for many years in Sligo in my 20s and it often went like this...youd get soaked 3 days in a row then dodge all the rain for the next month.

Mathematically Id say theres 1100mm of rain in Sligo a year. Over half of this falls at night as often in colder weather the rain seems to intensify after darkness so thats 500mm give or take left. Heavy showers that are short lived use up at least half of this leaving around 200mm then prolonged rainfall but at different times not always the morning commute and drizzle in July and August can be the worst.

So in conclusion Spring and early Summer is probably the best times to cycle in Sligo

November December and surprisingly August the worst months for rain

Oneiric 3

Just from my own station in Galway (admitedly one of the drier parts of the county) and based on 5 min readings, rain rates are only recorded about 3 to 5% of the time. I think what distorts actual perceptions about rain frequency in Ireland is the very poor drying from October to about March, and the fact that more often than not, the sky looks like it would be giving rain when it actually isn't. Keep in mind also that the west and northwest of Ireland are amongst the least sunniest places on the planet. Claremorris, in south Mayo, when it did record sunshine, had the lowest annual average sunshine totals in the world.

Oneiric 3

pauldry wrote: »

Read that Galway article too. They must be using Mace Head.

I sometimes wonder about Mace Hd's rainfall readings. Already this year, it is coming in with a lower total than Athenry, and has done for every year since at least 2016:

https://www.met.ie/climate/available-data/monthly-data


despite claiming to have a higher annual average total.

Oneiric 3

snowstreams wrote: »

Though I think 2007-2008 were very wet years in Dublin.
.

They were wetter in Galway, and that includes both these infamous summers.

We just didn't make quite the fuss at the time.

Summer 2007 tots:
Dublin Apt: 349mm
Casement: 391.4mm
Galway (UCG) 391.6mm


Summer 2008 tots:
Dublin Apt: 377.7mm
Casement 344.4mm
Galway (UCG) 519.1mm

(Met Eireann)

Xenji

Castlebar has had just over 15000mm of rain for the last 10 years, that's about 4.1mm of rain a day if you go mathematically, but we know that is not the case, but we have actually recorded just 726 days with no percipitation in those 10 years, so you could say on average it rains nearly 80% of the time, but again that is just simplifying it.