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20010608: 20010606: Decoding upper-air data manually with dcuair: time problem

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  • Subject: 20010608: 20010606: Decoding upper-air data manually with dcuair: time problem
  • Date: Fri, 08 Jun 2001 11:03:27 -0600
Christian,

I didn't see that CYVP made a 12Z sounding that day.
Several possible explanations:

1) CYVP could have coded the observation incorrectly (eg used local time
rather than UTC time). 

2) The data was retransmitted, if it was not received earlier.


You'd have to contact the office in question to find out why they coded the time
as 7Z. You could see if the data "seem" to fit a 12Z profile if you believe
that the coded time is incorrect.



Steve Chiswell
Unidata User Support



>From: Christian Page <address@hidden>
>Organization: UCAR/Unidata
>Keywords: 200106080734.f587Ylp19225

>
>Hi,
>
>Thanks for the info. I didn't know that the broadcast time could be so differe
> nt
>than the sounding nominal time...
>
>Christian Page
>
>On Wed, 6 Jun 2001, Unidata Support wrote:
>
>>
>> The decoded data are correct. The nominal sounding time is 7Z. The decoder w
> ill store all
>> soundings between 0530Z and 0730Z as a 6Z report.
>>
>> The WMO broadcast time of the bulletins are: CYVP 061240
>>
>> This header time has nothing to do with the observation tinme of the soundin
> g. The sounding
>> date/time are provided in the upperair code below as: 5607x
>>
>> The date/time group is interpretes as:
>> 56 = 6th day of month (with 50 added for wind speeds in knots)
>> 07 =  the sounding observation nominal time, eg 7Z. This is stored in the de
> coded data
>>      as STIM = 0700.
>> the last of the 5 digits, x, is the termination level for data in the indivi
> dual section.
>> Eg, in the TTAA part, 56071, means that the data terminates below 100mb.
>>
>