That statistic on the likelyhood of it raining on a commute.

le_patron

Anyone remember it or got link to it ? I remember it being x many days a year, and lower than you'd expect.

Cheers

hondafanatic

If my bag + contain waterproof clothes = No rain.

If my bag + just my pack lunch = Rain

mattybain

le patron wrote:

Anyone remember it or got link to it ? I remember it being x many days a year, and lower than you'd expect.

Cheers

I reckon here in Manchester it's about 12%, this is based on there being 140.4 wet days a year (less than the UK average of 156) and commuting 2 hours a day.

However there are loads of assumptions in this, but it does feel about right.

Coriander

I have no link to it, but I have heard many times that in London, if you commute both ways every working day of the year then you will be cycling in the rain 12 times.

Seems a little optomistic, but not outrageously so.

mattybain

mattybain wrote:

le patron wrote:

Anyone remember it or got link to it ? I remember it being x many days a year, and lower than you'd expect.

Cheers

I reckon here in Manchester it's about 12%, this is based on there being 140.4 wet days a year (less than the UK average of 156) and commuting 2 hours a day.

However there are loads of assumptions in this, but it does feel about right.

Also the web page I got the 140.4 wet days also says "Summers in Manchester are pleasant " so I am not sure how much I can rely on that figure

Eat My Dust

I remember the last time this came up. I believe the figure was 18 times in a year. I think it was Bonj who posted it. I'm sure it rained for about 3 solid months straight after the posting (which I had originally agreed with) :evil:

don_don

I've been wet plenty of times (juvenile snigger) but I don't think it can be more than 10-15% of my daily commutes.

However, I've been taking my daughter to nursery in her bike seat twice a week for over a year and I've only had to put her waterproofs on once. Not bad going I think

greg66_tri_v2.0

The clothes guy at Condor told me it was 11.

As I've observed in the past, whoever collated that stat was quite clearly reliant on (a) his digits and (b) his pen to keep tally.

itboffin

I've heard the 12 day theory a few times and it BS!!!

There's a book called "The Wrong Kind of Snow" that looks at average weather patterns over the last 50 years plus a few major weather related events.

and I quote

"Over the last year of writing we've witnessed the hottest July ever, the warmest autumn, the wettest December and worst floods for sixty years. Not bad for twelve months. But even in Britain, with all its variety, we only see, on average, ten lightning shows a year. Just eight days will be properly foggy. We may get as few as twenty frosts, these days, and perhaps fifteen days of failing snow. Seventy seven days will be predominantly sunny"

Clearly this book was not written this year as I do not recall see any sun this autumn.

12 days of rain my big fat arse...

Sorry the subject makes me see red, don't even start talking about the wind. :evil:

Coriander

Ah, but ITB, it doesn't mean it rains on only 12 days a year, it means that it will be raining between, say, 7 and 9am and 4 and 6pm Monday to Friday only 12 times a year.

Which given how rarely I ride in the rain or use a brolly seems about right.

jonginge

I can only remember getting rained on during the commute a couple of times in the last six months or so. Gettting damp by riding on still wet roads is a much higher, but not disastrous, total.

itboffin

Coriander wrote:

Ah, but ITB, it doesn't mean it rains on only 12 days a year, it means that it will be raining between, say, 7 and 9am and 4 and 6pm Monday to Friday only 12 times a year.

Which given how rarely I ride in the rain or use a brolly seems about right.

Touché

I am led to believe that drizzle is not counted as rain WTF is up with that I ask you.

mattybain

itboffin wrote:

Coriander wrote:

Ah, but ITB, it doesn't mean it rains on only 12 days a year, it means that it will be raining between, say, 7 and 9am and 4 and 6pm Monday to Friday only 12 times a year.

Which given how rarely I ride in the rain or use a brolly seems about right.

Touché

I am led to believe that drizzle is not counted as rain WTF is up with that I ask you.

Well given that it rains 156 days on average in the UK I think 12 is way too low, I guess it depends on how long a rain event is and how long your commute is.

However the maths of it all is doing my head in and giving me a headache, not helping my 15 mile battle with the wind!!

edhornby

mattybain wrote:

Well given that it rains 156 days on average in the UK I think 12 is way too low, I guess it depends on how long a rain event is and how long your commute is.

the rain starts the minute I clip into my pedals !!! I count drizzle if it soaks through any non-rainproofed clothing, which isn't much other than a bit of mist

incidentally Matty - if you commute down Bury Old Rd and see a guy with a red helmet and riding a blue fixed wheel (about 8:15ish), that's me :-)

cee

remember though that 365 days in a year, only about 240 of which are working days (based on 48 * 5 day working weeks).
i only commute before 9 and after 5.30, so will miss all the rain that starts at 9.30 and stops at 5....

coupled with those days that you just get a lucky path through the rain in the area you are in.

And remember that if it does persist all day, then while it feels like we get soaked twice, they have only counted it as once..i.e. on one day.

ansbaradigeidfran

mattybain wrote:

Also the web page I got the 140.4 wet days also says "Summers in Manchester are pleasant " so I am not sure how much I can rely on that figure

Perhaps the weather is pleasant, and Manchester's just letting the side down.

With regards to the number of rainy commutes...

There's a figure quoted here of 156 rainy days in the UK on average. It doesn't rain all day for 156 days, though. It could rain while you're at work.
I couldn't find any numbers online about how long it actually rains on a rainy day, so I'm going to assume that it's the same sort of ratio (it rains on 156/365=0.427 days of the year) for how much of a rainy day actually has rain. Note that this isn't statistically accurate: it's a big fudge.
Say that you spend an hour each way commuting. If so, then you're out in the elements 2/24 of the time. The probability of being caught in the rain on any day would thus be:

Probability of being out * probability of a rainy day * probability of raining at the time

or 2/24 * 156/365 * 0.427 = 0.0152

Or 5.5 days of the year. Take it with a pinch of salt, as one of the figures is a bit questionable.

ansbaradigeidfran

Hold on, I forgot that the rainy day needs to be a work day for you to care.

Probability of a rainy work day * probability of being out in it

(156/365 * 240/365) * (2/24 * 0.427) = 0.0100

That'd make 3.65 soggy days. The numbers are off somewhere, though.

Crapaud

Eat My Dust wrote:

I remember the last time this came up. I believe the figure was 18 times in a year. I think it was Bonj who posted it. I'm sure it rained for about 3 solid months straight after the posting (which I had originally agreed with) :evil:

ISTR 21 days.

May 2004 was the wettest May on record in Glasgow. I did my 7 mile e/w commute 6 days a week with extra miles on Mon, Wed and Friday and at least 120 miles on each Sunday. I didn't get rained on once! :?

From late June to mid Sept of that year, I cycled across Canada and only got rained on 3 - 4 times!

Bizzare.

mattybain

ansbaradigeidfran wrote:

Hold on, I forgot that the rainy day needs to be a work day for you to care.

Probability of a rainy work day * probability of being out in it

(156/365 * 240/365) * (2/24 * 0.427) = 0.0100

That'd make 3.65 soggy days. The numbers are off somewhere, though.

Why are you * by 0.427 twice? isn't the 156/365 the ony time you need it?

Also I dont think 2/24 is accurate, imagine if it did rain all day then the probablity you would get wet would be 1 and not 2/24. This is the fudge in the calculation, if an average rain event was 4 hours then the probability would be 1/3? I think using 2/24 assumes rain lasts on average less than 1 hour.

However I could be wrong, I am not a statiscian!!

daniel_b

Actual working days would be more like 222 though, I base that on:

The average punter in my experience has 25 days leave.
Working days in a year = 52*5 = 260, -25 = 235, then there are 13 public bank holidays (I think) which makes it 222 days by my calculations.

Not sure if that helps or hinders your calculations

Dan

Mike Healey

After running the 2-hr Kids Saturday bike club for 10 years, I can report that it is very rare that it rains during the session, perhaps twice/yr.

We have only cancelled for bad weather 10 times during that period and even then, it occasionally turned out that we could have run it, as the weather eased up between the phoning round and the 10.30 start.

Of course, we have the inestimable advantage of meeting in Yorkshire - it might be different across t'other side of the Pennines - they have turrible weather in Lancashire

dang65

itboffin wrote:

I am led to believe that drizzle is not counted as rain WTF is up with that I ask you.

I think it's drizzle which gives car drivers the impression that it rains a lot during the commute and they would get soaked all the time if they cycled. This is because only a small amount of drizzle is enough to mist up a windscreen and need the wipers switched on, so it feels like it's "raining". When you're cycling, a bit of drizzle has pretty much no effect and is even quite pleasant.

I kept a note of the weather on my commute in Manchester for about 10 months a few years ago. Proper soakings were incredibly rare, and the ones I did get were almost always on the way home when it was no big deal anyway. I think I got soaked once on the way to work during that whole period. That's not to say it didn't pour with rain most days, just not during commuting hours.

I think if we all got soaked as often as non-cyclists think we do then many of us would give up, because a proper soaking is uncomfortable but, as long as it only happens on rare occasions, it's fun as well.