In article ,
Martin wrote:

The Dutch Met Office does but they try to cover the whole country with
just one forecast.

That's reasonable, given its size and lack of terrain, but they
really should have some adjustments for the times and probabilities
that a front is passing through or hovering there.

Temperatures between the north and south and between the coast and the
east can very different.

Other than due to the qualifications I mention above, not really.
The whole country's no larger than the south-eastern corner of
England, and the weather is no more variable over it.

It's not the area, but the shape that makes the difference.

The extreme north is on the same latitude as Sheffield the extreme
south is on the same latitude as Bournemouth
The east can have continental weather whilst the west has Atlantic
weather.
The north can be bitterly cold and dry, whilst the south is wet and
warm.
The coast is in two Met Office Sea Areas.

All of that is true of East Anglia, and the reasons are as I said.
Weather fronts can be quite sharp.

Sort of. It was because Old Fred had many decades of experience for
that particular location, and used his subconscious. The general
forecasts were based on the science, which was basic, and the data,
which was almost non-existent. They were little better than crude
guesswork.

Experimental long range forecasting was 51% correct. Short range was
much better than pure luck. Observations were made several times a day
at many locations in UK and all over Europe and on three weather ships
that were stationed mid Atlantic.

Heck - I can do much better than pure luck, using no equipment and
no calculation! It wasn't until the satellites that even the short-
term forecast became significantly better than "The same as the day
before". And THAT is the fair test.

That was the comment made when the figure for long range forecast
accuracy was provided to parliament.

And it's true, so please don't compare against pure luck. That's a
political trick, not science.

I've sailed all my life. The weather is often not the same where I
live and where I keep my boat 60 miles north of where I live. It is
almost always far windier where I keep my boat.

Sigh. I have worked with meteorologists (loosely, but in several
contexts) and in related areas, over many decades. Such variations
are common, and they are entirely due to either microclimate or
the weather front effect I mention above.

The forecaster mentally compared the current situation with what the
forecaster remembered happening next, when the situation occurred on
previous occasions. The forecasters on airfields didn't spend their
lives in one location. It's a long time ago but AFAIR they spent
around three years before moving somewhere else. On the weather ships
it was less than three years.

The former is what I said.

You said decades.

Yes. Decades of experience.

I will take your word for the latter!

My first job, in 1966, was physically within the Met. Office, and I
was programming a Mercury. It was completely inadequate for anything
as tricky as a forecast, though that was the sort of programming I
was trying to do.

When I left in 1964, they already had a KDF9. The Mercury was used
for modeling

And it wasn't powerful enough even for that.

Depending in the model.

That is simply wrong. Did YOU use one for atmospheric modelling?
Because I did. And the task that I was tackling was vastly simpler
than weather prediction.

In one of my courses,
I point out that my hearing aids are 10,000 times more powerful
than a Mercury, and a damn sight less than 10,000th of the size!

On the other hand it was amazing what could be done in the 1960s with
mini computers with 16K memories and 1Mhz cycle and slower times, that
were coded in assembler and didn't have large general purpose bloated
operating systems in them.

Multiple deep sighs. You are corresponding with someone who did just
that - except that it wasn't assembler on the Mercury, but machine
code, in octal. Also, from your postings, I doubt that you know the
science involved - I don't claim to, but I do know enough to know
that the correct science couldn't be modelled even on a KDF9, let
alone a Mercury. Having to use known unrealistic models to fit
within the resources available was part of the problem, right up
until the 1980s.

This is getting ridiculous, so I shall stop here.


Regards,
Nick Maclaren.