[Met_help] Using MET with fcst_lead >= 100 h

[John Halley Gotway]

John,

I checked and found out that this really is a problem for the
STAT-Analysis and MODE-Analysis tools.  When I ran STAT-Analysis and
specified a lead time of "-fcst_lead 114", it errored out with an error
message about not being able to parse that time.

So I modified the library code which parses these strings to allow for the
lead hours to be either 2 or 3 digits long.

I've posted the fix to:
http://www.dtcenter.org/met/users/support/known_issues/METv2.0/index.php

Thanks for pointing out this problem, and please let me know if you
uncover any more issues.

Thanks,
John

> John,
>
> Thanks for the clarification of everything.
>
> I'll let you know if I uncover any other problems with triple-digit lead
> times, but, otherwise, I'll await your fix.
>
> Thanks for the quick responses!
>
> John
>
> On 12/23/09 4:37 PM, John Halley Gotway wrote:
>> John,
>>
>> Regarding WPP, I really don't think that you'll have a problem.  I'm
>> currently working on a project with folks from NOAA where we're creating
>> forecasts out to 114 hours and are running the most recently released
>> version of WPP just fine.  You would only potentially have an issue if
>> you
>> were running your forecasts out>  255 hours.
>>
>> Regarding issues with MET, you're probably correct.  I think this would
>> come up in your use of the MODE-Analysis and STAT-Analysis tools.
>> That's
>> the place you'd be specifying the forecast lead time in the config file
>> or
>>   on the command line.  I believe it would be a pretty easy fix
>> involving
>> changes to the "timestring_to_sec" routine in the file
>> METv2.0/lib/vx_cal/time_strings.cc.
>>
>> However, before making any changes, I'd like to do some testing to make
>> sure it really is a problem.  And once I verify that, I'll work on a
>> fix.
>> If I isolate the problem and come up with a fix, I'd post it to the MET
>> website and update the package of bug fixes.
>>
>> I'll let you know how it pans out.  Please let me know if, in your use
>> of
>> MET, you find another place where it's a problem to have forecast hours>
>> 99.
>>
>> Thanks,
>> John
>>
>>
>>> Hello John,
>>>
>>> Thanks for the prompt response. Perhaps I had briefly come across the
>>> WPP email and thought it was actually related to MET...
>>>
>>> I believe - according to the user manual - that MET allows the user to
>>> specify forecast lead time as HH[MMSS], which seems to me to prevent
>>> leads times>  99h. Am I mistaken?
>>>
>>> Regarding WPP...I intend to verify precip accumulation in MET for a
>>> year-long series of 5.5-day forecasts that overlap at the beginning of
>>> each forecast run to avoid spin-up problems. It's a pretty standard way
>>> of generating year-long WRF simulations. However, that means that I
>>> will
>>> be applying WPP to WRF forecasts with forecast lead times of 12 h to
>>> 132
>>> h. I hadn't anticipated any problems with WPP, unfortunately. I have a
>>> vague memory that someone had come up with a fix for the long-lead time
>>> problem, but I'm not sure. Would you be able to investigate the status
>>> for me?
>>>
>>> Thanks.
>>>
>>> John
>>>
>>> On 12/23/09 2:51 PM, John Halley Gotway wrote:
>>>
>>>> John,
>>>>
>>>> I looked back through the old MET-Help emails and couldn't find
>>>> anything
>>>> that would explain a problem of using fcst_lead>= 100 hours.  So I'm
>>>> not
>>>> aware of a problem with that.  I did find one email
>>>> related to this but I believe that was due to an incorrectly packed
>>>> GRIB
>>>> file, not a problem in MET itself.
>>>>
>>>> However, there are some issues in WPP (WRF-PostProcessor) for
>>>> accumulated precip when the forecast lead time extends beyond 255
>>>> hours.
>>>>   The time value of 255+ overflows the single byte that's
>>>> allocated in the GRIB record to store that time info.  This is mostly
>>>> an
>>>> issue for accumulated precip since you have to store 2 times in the
>>>> GRIB
>>>> record - accumulation starting and ending times.  I'm
>>>> not sure of the status of this issue, but if you run across it, I can
>>>> look into it more.
>>>>
>>>> I'd say, proceed with trying to use MET to verify forecasts>= 100
>>>> hours.
>>>>   And if you run into any problems, just let us know through
>>>> met_help at ucar.edu.
>>>>
>>>> If you haven't already done so, I would suggest retrieving the latest
>>>> set of bug fixes for METv2.0 from:
>>>> http://www.dtcenter.org/met/users/support/known_issues/METv2.0/index.php
>>>>
>>>> Hope that helps,
>>>> John Halley Gotway
>>>> johnhg at ucar.edu
>>>>
>>>> John Henderson wrote:
>>>>
>>>>
>>>>> Hello,
>>>>>
>>>>> When first I installed WRF-MET I believe I saw a discussion somewhere
>>>>> about how to apply WRF-MET to forecasts that require a fcst_lead of
>>>>> at
>>>>> least 100 h, however, I can't seem to find it now. Can you point me
>>>>> in
>>>>> the right direction?
>>>>>
>>>>> Thanks.
>>>>>
>>>>> John Henderson
>>>>> AER, Inc.
>>>>>
>>>>> _______________________________________________
>>>>> Met_help mailing list
>>>>> Met_help at mailman.ucar.edu
>>>>> http://mailman.ucar.edu/mailman/listinfo/met_help
>>>>>
>>>>>
>>>
>>
>>
>