On Jun 5, 7:54*pm, Graham Easterling
wrote:
On 5 June, 19:25, Len Wood wrote:





On Jun 5, 6:25*pm, ned flanders wrote:

The probability of correct forecasting is something that has been
rattling around in my head for a while.

If on Day 1 of a 5 day forecast I'm told Rain is on the way only for
this forecast to change between rain/dry (for example) *over the next
three days and then its actually dry on day 5, the forecast on day 1
was utterly worthless.

What probability of a likely event happening triggers it becoming a
'forecast'. Surely it needs to be 75% likely as that would mean it is
twice as likely to happen, as not.

Also why is that probabilty of a forecast never mentioned on tv/radio/
media forecasts. Is it because Jo Public has dumbed down so much over
the last few years that he has no concept what Porbability is?

To be fair, as Victoria Coren wrote in the Observer last Sunday:
The Met Office recently had its budget cut by £4.3 million. That may
not sound like much, but it was a loss of more than 20 million pine
cones.

Len Wood
Wembury

Pine cones? Down here we're more up to date!http://www.redbubble.com/people/bcim...074-7-you-what

Graham
Penzance

http://www.turnstone-cottage.co.uk/- Hide quoted text -

- Show quoted text -

OK Graham,
I know you've got superior seaweed in Cornwall!
But I am not sure the Mousehole Barometer is foolproof.

Len Wood
Wembury, SW Devon

On Jun 7, 8:07*pm, Len Wood wrote:
On Jun 5, 7:54*pm, Graham Easterling
wrote:





On 5 June, 19:25, Len Wood wrote:

On Jun 5, 6:25*pm, ned flanders wrote:

The probability of correct forecasting is something that has been
rattling around in my head for a while.

If on Day 1 of a 5 day forecast I'm told Rain is on the way only for
this forecast to change between rain/dry (for example) *over the next
three days and then its actually dry on day 5, the forecast on day 1
was utterly worthless.

What probability of a likely event happening triggers it becoming a
'forecast'. Surely it needs to be 75% likely as that would mean it is
twice as likely to happen, as not.

Also why is that probabilty of a forecast never mentioned on tv/radio/
media forecasts. Is it because Jo Public has dumbed down so much over
the last few years that he has no concept what Porbability is?

To be fair, as Victoria Coren wrote in the Observer last Sunday:
The Met Office recently had its budget cut by £4.3 million. That may
not sound like much, but it was a loss of more than 20 million pine
cones.

Len Wood
Wembury

Pine cones? Down here we're more up to date!http://www.redbubble.com/people/bcim...074-7-you-what

Graham
Penzance

http://www.turnstone-cottage.co.uk/-Hide quoted text -

- Show quoted text -

OK Graham,
I know you've got superior seaweed in Cornwall!
But I am not sure the Mousehole Barometer is foolproof.

Len Wood
Wembury, SW Devon- Hide quoted text -

- Show quoted text -

Think I probably didnt put my questions clearly enough. What I was
trying to ask was what is the accepted probability that a weather
event will occur for it to become a forecast??

On Jun 7, 10:10*pm, ned flanders wrote:
On Jun 7, 8:07*pm, Len Wood wrote:





On Jun 5, 7:54*pm, Graham Easterling
wrote:

On 5 June, 19:25, Len Wood wrote:

On Jun 5, 6:25*pm, ned flanders wrote:

The probability of correct forecasting is something that has been
rattling around in my head for a while.

If on Day 1 of a 5 day forecast I'm told Rain is on the way only for
this forecast to change between rain/dry (for example) *over the next
three days and then its actually dry on day 5, the forecast on day 1
was utterly worthless.

What probability of a likely event happening triggers it becoming a
'forecast'. Surely it needs to be 75% likely as that would mean it is
twice as likely to happen, as not.

Also why is that probabilty of a forecast never mentioned on tv/radio/
media forecasts. Is it because Jo Public has dumbed down so much over
the last few years that he has no concept what Porbability is?

To be fair, as Victoria Coren wrote in the Observer last Sunday:
The Met Office recently had its budget cut by £4.3 million. That may
not sound like much, but it was a loss of more than 20 million pine
cones.

Len Wood
Wembury

Pine cones? Down here we're more up to date!http://www.redbubble.com/people/bcim...074-7-you-what

Graham
Penzance

http://www.turnstone-cottage.co.uk/-Hidequoted text -

- Show quoted text -

OK Graham,
I know you've got superior seaweed in Cornwall!
But I am not sure the Mousehole Barometer is foolproof.

Len Wood
Wembury, SW Devon- Hide quoted text -

- Show quoted text -

Think I probably didnt put my questions clearly enough. What I was
trying to ask was what is the accepted probability that a weather
event will occur for it to become a forecast??- Hide quoted text -

- Show quoted text -

That's actually an extremely good question. Ally it to why and how the
decisions are made as to how those probablilities are calculated (an
80% chance of a weather event occurring leads to a red warming on the
charts - how did they get to 80%?) and you have the "secret" of
weather forecasting.

I always accept that the bottom line to a forecast is skill and
experience and the MetO forecasters are the best in this part of the
world, but skill and experience actually equals subjectivity; but
here's the PR achilles heel of the MetO. Instead of sharing the
"secret", in terms of forecast outcome probabilities and admitting
that there are times when the forecast is unlikely to achieve outcome
(especially in timescales of over a week) it is presented as if it
will come true and there is no analysis, except in extreme instances,
of why forecasts turned out to have gone mammaries skywards.

Why can't the MetO PR department see this and include their target
audience so much better? If they did, people in general, would feel so
much better about their national weather service provider. So much
scientific talent, so much superb, world-leading research and so often
a PR disaster area. It must make Met Office employees cringe!

On Jun 7, 10:36*pm, Dawlish wrote:
On Jun 7, 10:10*pm, ned flanders wrote:





On Jun 7, 8:07*pm, Len Wood wrote:

On Jun 5, 7:54*pm, Graham Easterling
wrote:

On 5 June, 19:25, Len Wood wrote:

On Jun 5, 6:25*pm, ned flanders wrote:

The probability of correct forecasting is something that has been
rattling around in my head for a while.

If on Day 1 of a 5 day forecast I'm told Rain is on the way only for
this forecast to change between rain/dry (for example) *over the next
three days and then its actually dry on day 5, the forecast on day 1
was utterly worthless.

What probability of a likely event happening triggers it becoming a
'forecast'. Surely it needs to be 75% likely as that would mean it is
twice as likely to happen, as not.

Also why is that probabilty of a forecast never mentioned on tv/radio/
media forecasts. Is it because Jo Public has dumbed down so much over
the last few years that he has no concept what Porbability is?

To be fair, as Victoria Coren wrote in the Observer last Sunday:
The Met Office recently had its budget cut by £4.3 million. That may
not sound like much, but it was a loss of more than 20 million pine
cones.

Len Wood
Wembury

Pine cones? Down here we're more up to date!http://www.redbubble.com/people/bcim...074-7-you-what

Graham
Penzance

http://www.turnstone-cottage.co.uk/-Hidequotedtext -

- Show quoted text -

OK Graham,
I know you've got superior seaweed in Cornwall!
But I am not sure the Mousehole Barometer is foolproof.

Len Wood
Wembury, SW Devon- Hide quoted text -

- Show quoted text -

Think I probably didnt put my questions clearly enough. What I was
trying to ask was what is the accepted probability that a weather
event will occur for it to become a forecast??- Hide quoted text -

- Show quoted text -

That's actually an extremely good question. Ally it to why and how the
decisions are made as to how those probablilities are calculated (an
80% chance of a weather event occurring leads to a red warming on the
charts - how did they get to 80%?) and you have the "secret" of
weather forecasting.

I always accept that the bottom line to a forecast is skill and
experience and the MetO forecasters are the best in this part of the
world, but skill and experience actually equals subjectivity; but
here's the PR achilles heel of the MetO. Instead of sharing the
"secret", in terms of forecast outcome probabilities and admitting
that there are times when the forecast is unlikely to achieve outcome
(especially in timescales of over a week) it is presented as if it
will come true and there is no analysis, except in extreme instances,
of why forecasts turned out to have gone mammaries skywards.

Why can't the MetO PR department see this and include their target
audience so much better? If they did, people in general, would feel so
much better about their national weather service provider. So much
scientific talent, so much superb, world-leading research and so often
a PR disaster area. It must make Met Office employees cringe!- Hide quoted text -

- Show quoted text -

I am not sure Met Office bods know why on some occasions the numerical
model output goes mammaries skywards as you so delicately put it Paul.
There are a number of possible reasons (handling of the physics,
maths, feedbacks, quality and quantity of data...) and it is all to do
with the construct of the model and its ability to forecast some
weather situations better than others.
Do the public just want more honesty when forecasts go wrong? This is
more often than Met Office care to admit if you want a very local
detail forecast, and one for more than 5 days ahead. I think the
public might just view the Met office as whingeing if they tried each
time to explain the uncertainties when the forecast goes haywire.
Ned, you started the discussion talking about the forecasting of rain.
The timing of cloud and quantity of rain is one of the more difficult
things to forecast. So many feedbacks across all time and space
scales.
Especially showery rain.

Len Wood,
Wembury, SW Devon