[wxqc] Spike in quality report?

[Mike Barth]

I've looked into this case: the MADIS ingest processing failed for the
APRSWXNET data at 1/2 09:37 GMT.  What happened was that all stations
whose ID's are alphabetically higher than AP146 had the wrong data
(data from station N+1 in the input file got mistakenly assigned to
station N).  I went back and looked at the last 3 weeks of data and
found no other occurrence of this problem, so it appears to be an
isolated incident.

If anyone notices this same pattern happening again, please let me know.
The thing to look for is a sudden jump in the observation values, closely
followed by a return to normal.  (This has nothing to do with occasional
spikes in the analysis or error values).  Also, this won't be isolated
to just one variable (e.g., temperature) but will happen to all of them
at the same time.

Thanks,

Mike

On Tue, 3 Jan 2006 dshelms at comcast.net wrote:

> Hi Evan,
>
> I think the entire QCMS analysis has a hick-up for an hour (a single 15 minute time step) then recovered, maybe its was a end-of-year roll-over thing?
>
> Mike Barth should be able to advise us on the situation.
>
> Cheers,
>
> Dave
> CW0351
>
>
> -------------- Original message ----------------------
> From: "Evan Bookbinder" <Evan.Bookbinder at noaa.gov>
>> This might be something the software developers should be made aware of.
>> We'll occasionally see a random barometric spike here at the WFO too,
>> which I assume is simply a bad packet. Bad packet or bad measurement
>> aside, I can't imagine that it would be too terribly difficult to have
>> the decoding software compare the current value to the last stored value
>> within so many seconds (in case the system has been off for a while). If
>> the difference exceeds some arbitrary value, toss it (or at least store
>> it and flag it).
>>
>> What I find most interesting is that two spikes occurred from two nearby
>> stations almost simultaneously. The barometer went in opposite
>> directions. My guess is that something causing a lot of interference
>> passed through your locations, causing a bad set of packets to be
>> ingested. The time is a bit off, but we'd see that here at the NWS when
>> the upper air balloon was launched. The signal overwhelmed one of our
>> satellite received systems on a very nearby  frequency. Time to call the
>> UFO reporting center :)))))
>>
>> Evan
>>
>> Gerald Buxton wrote:
>>
>>> I have seen this too Jim, on my qc reports. I believe the last time I
>>> saw it, I looked back at the weather data link and saw that one of the
>>> reportings was way high (I believe it was barometer)... don't know
>>> though whether that was actually sent by the WXTrak device, or the
>>> packet was decoded wrong by a receiving station.
>>>
>>> Jerry
>>> AR194
>>> N0JY
>>>
>>> --Original Message Text---
>>> *From:* Jim McMurry
>>> *Date:* Tue, 3 Jan 2006 06:57:50 -0600
>>>
>>> I'm just wondering if anyone has seen this happen before and knows
>>> what might have caused it.
>>>
>>>
>> _http://weather.gladstonefamily.net/qchart/C3882?date=20060103&addnl=AR825&Add+t
>> o+charts=Add+to+charts&.cgifields=addnl_
>>>
>>> Just prior to 1000Z it shows an extreme spike that doesn't show up in
>>> my logs. The same thing happened to AR825 which is the closest station
>>> to me.
>>>
>>> None of the other close stations seemed to have the same thing happen.
>>> Also wondering whether a spike like this affects our averages or if
>>> the system recognizes it as an anomaly and "throws it out".
>>>
>>> Jim McMurry
>>> C3882
>>>
>>>
>>>
>>> ------------------------------------------------------------------------
>>>
>>> _______________________________________________
>>> wxqc mailing list
>>> wxqc at lists.gladstonefamily.net
>>> http://pond1.gladstonefamily.net:8080/mailman/listinfo/wxqc
>>>
>>> The contents of this message are the responsibility of the author.
>>>
>
>
>
>