================================================== ==================
This posting expresses the personal view and opinions of the author.
Something which everyone on this planet should be able to do.
================================================== ==================

1900 3/10/04

Rainfall now stands at 18.7 mm for this event, so nothing severe (or even heavy)
yet.
Still continuous moderate, occasionally heavy rain, however.

Wind still light to moderate with max gust of just 22 knots.
Took a wet walk up to 450m this afternoon and wind only force 4-5 occasionally 6
up there.

Long way to go yet though.

Will.
--

" A cup is most useful when empty "
-------------------------------------------------------------------------------
A COL BH site in East Dartmoor at Haytor, Devon 310m asl (1017 feet).

mailto:
www: http://www.lyneside.demon.co.uk

DISCLAIMER - All views and opinions expressed by myself are personal
and do not necessarily represent those of my employer.
-------------------------------------------------------------------------------

I'm curious WIll, is the 18.7mm value obtained from your new Davis VP?
The reason I ask, is I thought the metric settings accumulated
rainfall in 0.2mm increments, so I would have expected 18.6 or 18.8mm.

Looking forward to seeing some of your data "live", well evenings and
weekends :-)


Keith (Southend)

***********************
Weather Home & Abroad
http://www.southendweather.net

On Sun, 3 Oct 2004 19:16:39 +0100, "Will"
wrote:


================================================= ===================
This posting expresses the personal view and opinions of the author.
Something which everyone on this planet should be able to do.
================================================= ===================

1900 3/10/04

Rainfall now stands at 18.7 mm for this event, so nothing severe (or even heavy)
yet.
Still continuous moderate, occasionally heavy rain, however.

Wind still light to moderate with max gust of just 22 knots.
Took a wet walk up to 450m this afternoon and wind only force 4-5 occasionally 6
up there.

Long way to go yet though.

Will.

Keith (Southend) wrote:

I'm curious WIll, is the 18.7mm value obtained from your new Davis VP?
The reason I ask, is I thought the metric settings accumulated
rainfall in 0.2mm increments, so I would have expected 18.6 or 18.8mm.

The Davis VP uses 0.01" increments (there were lots of bits of paper in
with my VP saying so!), so 0.254mm. Obviously all the nasty converting
to/from metric/imperial can be done automagically so they just make the
one size.

--
Jonathan Stott
Canterbury Weather: http://www.jstott.me.uk/weather/

================================================== ==================
This posting expresses the personal view and opinions of the author.
Something which everyone on this planet should be able to do.
================================================== ==================

Well spotted Keith !

No the 18.7 is from the manual raingauge. At the time my Davis VP was
under-reading at 18.0 mm. It is now 1935 local and is actually reading 19.3 mm
(which is an odd number). It measures rain in 0.01 inch tips (0.254mm tips). So
to read 19.3 mm it must have done 76 tips.
So it is possible to get odd numbers as it measures in inches and then converts.

This is one problem I have with AWS recording. With my manual gauge I can record
to 0.1 mm resolution. But the AWS is only capable of 0.254mm resolution. Or so I
believe ?

Be a little while yet before live data appears. But I *will* get the weatherlink
software as it will make instrument comparison much easier.
Thanks for the interest (in future I'll make it clear which instrument I'm
referring to) !

Will.
--
" A cup is most useful when empty "
-------------------------------------------------------------------------------
A COL BH site in East Dartmoor at Haytor, Devon 310m asl (1017 feet).

mailto:
www: http://www.lyneside.demon.co.uk

DISCLAIMER - All views and opinions expressed by myself are personal
and do not necessarily represent those of my employer.
-------------------------------------------------------------------------------

Keith (Southend) wrote in message ...
I'm curious WIll, is the 18.7mm value obtained from your new Davis VP?
The reason I ask, is I thought the metric settings accumulated
rainfall in 0.2mm increments, so I would have expected 18.6 or 18.8mm.

Looking forward to seeing some of your data "live", well evenings and
weekends :-)


Keith (Southend)

***********************
Weather Home & Abroad
http://www.southendweather.net

On Sun, 3 Oct 2004 19:16:39 +0100, "Will"
wrote:


================================================ ====================
This posting expresses the personal view and opinions of the author.
Something which everyone on this planet should be able to do.
================================================ ====================

1900 3/10/04

Rainfall now stands at 18.7 mm for this event, so nothing severe (or even
heavy)
yet.
Still continuous moderate, occasionally heavy rain, however.

Wind still light to moderate with max gust of just 22 knots.
Took a wet walk up to 450m this afternoon and wind only force 4-5 occasionally
6
up there.

Long way to go yet though.

Will.

================================================== ==================
This posting expresses the personal view and opinions of the author.
Something which everyone on this planet should be able to do.
================================================== ==================

As a postscript to my previous post.

I recorded 18.7 mm manually and 18.0 mm on my Davis VP.
Both instruments are set up OK (ie level, away from obstructions etc).
The quoted accuracy on my Davis for rainfall is +/- 4% .
4% of 18.0 mm is 0.72 mm, so it is operating perfectly accurately within the
manufacturers specs. Also what is my error in my measuring rainfall with a
tapered measuring cyclinder ? (I like to think I'm careful but it is so easy to
make mistakes).

I must say, I am extremely pleased with the performance of the VP so far (all of
one day :-) ) and as with all scientific instruments one must be fully aware of
their limitations.

Will.
--

" A cup is most useful when empty "
-------------------------------------------------------------------------------
A COL BH site in East Dartmoor at Haytor, Devon 310m asl (1017 feet).

mailto:
www: http://www.lyneside.demon.co.uk

DISCLAIMER - All views and opinions expressed by myself are personal
and do not necessarily represent those of my employer.
-------------------------------------------------------------------------------

Keith (Southend) wrote in message ...
I'm curious WIll, is the 18.7mm value obtained from your new Davis VP?
The reason I ask, is I thought the metric settings accumulated
rainfall in 0.2mm increments, so I would have expected 18.6 or 18.8mm.

Looking forward to seeing some of your data "live", well evenings and
weekends :-)


Keith (Southend)

***********************
Weather Home & Abroad
http://www.southendweather.net

On Sun, 3 Oct 2004 19:16:39 +0100, "Will"
wrote:


================================================ ====================
This posting expresses the personal view and opinions of the author.
Something which everyone on this planet should be able to do.
================================================ ====================

1900 3/10/04

Rainfall now stands at 18.7 mm for this event, so nothing severe (or even
heavy)
yet.
Still continuous moderate, occasionally heavy rain, however.

Wind still light to moderate with max gust of just 22 knots.
Took a wet walk up to 450m this afternoon and wind only force 4-5 occasionally
6
up there.

Long way to go yet though.

Will.

So I take it that Davis only now supply ONE tipping bucket range for
imperial measurement only and the metric is just a mathematical
conversion? I 'm sure when I bought my WM11 they used to have two
variants.

Must admit I still think mine under reads, I often try to get some
comparison with Shoeburyness, but being 6 miles away is not realy the
best way.

As was mentioned on a previous thread and I'm sure you would have
looked into this. Spurious readings can be a problem, I sorted mine
out by buying a surge protection socket(s).


Keith (Southend)

***********************
Weather Home & Abroad
http://www.southendweather.net

On Sun, 3 Oct 2004 20:03:31 +0100, "Will"
wrote:


================================================= ===================
This posting expresses the personal view and opinions of the author.
Something which everyone on this planet should be able to do.
================================================= ===================

As a postscript to my previous post.

I recorded 18.7 mm manually and 18.0 mm on my Davis VP.
Both instruments are set up OK (ie level, away from obstructions etc).
The quoted accuracy on my Davis for rainfall is +/- 4% .
4% of 18.0 mm is 0.72 mm, so it is operating perfectly accurately within the
manufacturers specs. Also what is my error in my measuring rainfall with a
tapered measuring cyclinder ? (I like to think I'm careful but it is so easy to
make mistakes).

I must say, I am extremely pleased with the performance of the VP so far (all of
one day :-) ) and as with all scientific instruments one must be fully aware of
their limitations.

Will.

"Keith (Southend)" wrote in message
...
So I take it that Davis only now supply ONE tipping bucket range for
imperial measurement only and the metric is just a mathematical
conversion? I 'm sure when I bought my WM11 they used to have two
variants.

Must admit I still think mine under reads, I often try to get some
comparison with Shoeburyness, but being 6 miles away is not realy the
best way.

As was mentioned on a previous thread and I'm sure you would have
looked into this. Spurious readings can be a problem, I sorted mine
out by buying a surge protection socket(s).


Keith (Southend)

***********************
You are correct about the Vantage Pro bucket size; this caused me a problem
when I first installed my station as it seemed from the instructions that
the bucket should have been metric size. It was an early station and the
literature has now been updated. I had to correct the readings for the error
which was easy to do in Excel.

Alan

"Will" wrote in message
...

================================================== ==================
This posting expresses the personal view and opinions of the author.
Something which everyone on this planet should be able to do.
================================================== ==================

As a postscript to my previous post.

I recorded 18.7 mm manually and 18.0 mm on my Davis VP.
Both instruments are set up OK (ie level, away from obstructions etc).
The quoted accuracy on my Davis for rainfall is +/- 4% .
4% of 18.0 mm is 0.72 mm, so it is operating perfectly accurately within
the
manufacturers specs. Also what is my error in my measuring rainfall with a
tapered measuring cyclinder ? (I like to think I'm careful but it is so
easy to
make mistakes).

I must say, I am extremely pleased with the performance of the VP so far
(all of
one day :-) ) and as with all scientific instruments one must be fully
aware of
their limitations.

Will.
--

If the rain has been heavy as you state then the tipping bucket design will
tend to under record - there were some readings at the time of the Boscastle
deluge that showed this could be substantial in size. I think the results
you have confirm that your guage is set up accurately as you say which makes
me think that any under recording at my site is due to the exposure. Living
in a garden surrounded by trees in other gardens makes it vitrually
impossible to get an ideal location for the station.

Alan

Only 1mm so far in NE Cumbria - rain shadow effect from the Lakeland Fells
perhaps !

--
Paul Crabtree
Brampton N.E. Cumbria 117m ASL
Climatological Station 7076

http://www.bramptonweather.co.uk