Hi,

I normally automatically reset all my data including Rainfall at Midnight on
my Davis Weather Monitor II. Is there a set time this should be done? It
seems logical to do it by the day but maybe standards specify a different
time?

Ray

Ray wrote:
Hi,

I normally automatically reset all my data including Rainfall at Midnight on
my Davis Weather Monitor II. Is there a set time this should be done? It
seems logical to do it by the day but maybe standards specify a different
time?

Ray

The climatological convention is that the "rain-day" is 09 GMT
to 09 GMT the next day. This also applies to max and min temperatures,
though many people, myself included, use an 09-21 period for max's and
21-09 for min's, but keeping the 09-09 period for rain. I'd say
resetting everything at midnight is not the best thing to do.

Tudor Hughes, Warlingham, Surrey. (COL station 54025).

I didnt think it was possible to set Davis to anything but the default
midnight to midnight.

Phil

"Ray" wrote in message
...
Hi,

I normally automatically reset all my data including Rainfall at
Midnight on my Davis Weather Monitor II. Is there a set time this
should be done? It seems logical to do it by the day but maybe
standards specify a different time?


There is a section in the FAQ relating to times for climatological
readings:-

http://homepage.ntlworld.com/booty.weather/FAQ/6D.htm

It's a difficult one, as to someone with an all-singing, all-dancing
AWS, they can't understand why rainfall should be 'artificially' defined
to the 09-09 standard, but if you can record *both* periods (and keep a
careful distinction between the two), then that would be useful.

Martin.

(PS ... stand back and wait for the debate!)


--
FAQ & Glossary for uk.sci.weather at:-
http://homepage.ntlworld.com/booty.weather/uswfaqfr.htm
and
http://booty.org.uk/booty.weather/metindex.htm

On Thu, 15 Jun 2006 05:57:14 +0100, "Phil Layton"
wrote:

I didnt think it was possible to set Davis to anything but the default
midnight to midnight.

The problem with the Davis (WM II in my case) is that you can define
the 'auto clear' time to whatever you like but the NOAA reports that
it generates ignore that and work on midnight to midnight. The
'bulletin' display, however, displays on the basis of the 'auto clear'
time.

For this reason I reset at midnight and all the readings that I quote
here are midnight to midnight.

--
Alan White
Twenty-eight miles NW of Glasgow, overlooking Lochs Long and Goil in Argyll, Scotland.
Webcam and weather:- http://windycroft.gt-britain.co.uk/weather
Some walks and treks:- http://windycroft.gt-britain.co.uk/walks

Felly sgrifennodd
Martin Rowley :
It's a difficult one, as to someone with an all-singing, all-dancing
AWS, they can't understand why rainfall should be 'artificially' defined
to the 09-09 standard, but if you can record *both* periods (and keep a
careful distinction between the two), then that would be useful.

I keep just one, 00-24. It will surely become a standard in years to come.
However, I have all the data (mostly 10 minute readings), and if anyone
really wants to examine my records at some point in the future, they can
if they wish work out the 9:00-9:00 figures - or indeed whatever takes
their fancy.

Adrian
--
Adrian Shaw ais@
Adran Cyfrifiadureg, Prifysgol Cymru, aber.
Aberystwyth, Ceredigion, Cymru ac.
http://users.aber.ac.uk/ais/weather/ uk

"Alan White" wrote in message
...
On Thu, 15 Jun 2006 05:57:14 +0100, "Phil Layton"
wrote:

I didnt think it was possible to set Davis to anything but the default
midnight to midnight.

The problem with the Davis (WM II in my case) is that you can define
the 'auto clear' time to whatever you like but the NOAA reports that
it generates ignore that and work on midnight to midnight. The
'bulletin' display, however, displays on the basis of the 'auto clear'
time.

For this reason I reset at midnight and all the readings that I quote
here are midnight to midnight.

--
Alan White
Twenty-eight miles NW of Glasgow, overlooking Lochs Long and Goil in
Argyll, Scotland.
Webcam and weather:- http://windycroft.gt-britain.co.uk/weather
Some walks and treks:- http://windycroft.gt-britain.co.uk/walks

I'm with Adrian on this one as surely midnight will become standard. However
as it's all copied into Excel I can do anything I wany with the data - well
I could if I had time.
It's quite easy to manipulate any system to record at 0900 - just lie when
you set the time, it'll believe you!!!!!!!!

--
David Mitchell, 70m amsl, Langtoft, East Riding of Yorkshire.

I record rain from 00-24 because that is what the Vantage Pro 2 records
and I cannot find any way of changing this to the official 09-09. I
suppose a computer program could be written to read in the data from
weatherlink and work out totals for the 0900-0900 but I'm certainly not
going to do that.

I don't think the 0900-0900 is good anyway as it means a rain day
ending in mid-morning (1000 BST) at this time of year. If I didn't have
an automatic station there's no way I could read a rain gauge at that
time every day.

The Vantage Pro records temperature from 00-24h as well but I do not
like this as it splits one nocturnal period into 2 separate recording
days. I record 2100-0900 mins and 0900-2100 maxes in a spreadsheet and
use these when sending my monthly return into COL.

Richard Slessor,
Hazlehead, Aberdeen.