[Met_help] [rt.rap.ucar.edu #46062] History for Re:PCP_COMBINE

[RAL HelpDesk {for John Halley Gotway}]

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  Initial Request
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Dear Sir/ Madam,

The forecast data which I would like to verify contains accumulated
precipitation data at six hourly intervals upto 72 hours. For example if the
the initial date is 24 December 2008 the forecast is upto 27 December 2008. If
I wish to verify the accumulated precipitaion for the period 25 to 26 December,
this means I am verifiying the 24 accumulated precipitaion for the 48 hour
forecast. I used pcp_combine to subtract the 24 hour from the 48 hour to get
the 24 hour accumulation from the 25-26 December. Then I verified with the 26
December observations, Is this method correct?

Thank you.

Regards,

Kumar



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  Complete Ticket History
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Subject: Re: [rt.rap.ucar.edu #46062] Re:PCP_COMBINE
From: John Halley Gotway
Time: Wed Apr 13 09:09:13 2011

Kumar,

Yes, that all sounds correct.  It sounds like your model output
contains precipitation accumulated over the course of the runtime.
Meaning your 24-hour forecast contains 24-hours of precip, and your
48-hour forecast contains 48-hours of precip.  If you're running the
WRF-ARW core, that's most likely how your precip is stored.  And if
that's the case, then, yes, using the "-subtract" option for
pcp_combine is the way to pull out smaller intervals.

Thanks,
John

On 04/12/2011 09:46 AM, RAL HelpDesk {for Kumarenthiran} wrote:
>
> Tue Apr 12 09:46:27 2011: Request 46062 was acted upon.
> Transaction: Ticket created by kumar at met.gov.my
>        Queue: met_help
>      Subject: Re:PCP_COMBINE
>        Owner: Nobody
>   Requestors: kumar at met.gov.my
>       Status: new
>  Ticket <URL:
https://rt.rap.ucar.edu/rt/Ticket/Display.html?id=46062 >
>
>
> Dear Sir/ Madam,
>
> The forecast data which I would like to verify contains accumulated
> precipitation data at six hourly intervals upto 72 hours. For
example if the
> the initial date is 24 December 2008 the forecast is upto 27
December 2008. If
> I wish to verify the accumulated precipitaion for the period 25 to
26 December,
> this means I am verifiying the 24 accumulated precipitaion for the
48 hour
> forecast. I used pcp_combine to subtract the 24 hour from the 48
hour to get
> the 24 hour accumulation from the 25-26 December. Then I verified
with the 26
> December observations, Is this method correct?
>
> Thank you.
>
> Regards,
>
> Kumar
>
>
>
> ----------------------
> MMD WebMail
> http://www.met.gov.my
>
>
> --
> This message has been scanned for viruses and
> dangerous content by MailScanner, and is
> believed to be clean.

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