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[Support #HKV-830940]: question about LDM IP address

> Hi,
> We've come up with a few more questions, as this is the first time we've ever 
> worked with LDM.
> First, some background:  To start, we'd like to get a stream of RAWS data, 
> specifically from stations located in Southern California.  We'd also like 
> some satellite imagery of Southern California, if possible.  I haven't been 
> able to find documentation regarding setting up the regular expression to 
> filter on specific things such as RAWS in Southern California.  Or even a 
> list of what stations are available.

Yes, when first discussed this w/Trina it was mentioned that we (Unidata) did 
not know specifically what data
was desired, we suggested the IDS|DDPLUS feedtype as it is the one that carries 
surface observations for operational
use. THE RAWS data you desire ~may not be included in that feed. It ~may be in 
the feed that originates at GSD (FSL) 
delivers MADIS and Meso-West surface observational data.


It would be helpful if we knew the station IDS of the desired RAWS, and I see 
above that you are asking us for a list of the stations :)

Does it need to be RAWS data or would METAR's work?  

> I also have no idea what format these streams are in when they're written to 
> file.  On our side we'd like to be able to process the RAWS data from each 
> individual station, and do our own transform on it into whatever format we 
> want to display it in.  So what would be the recommended way to store the 
> data stream?  Just to file?  Then I'm assuming we can just inspect the file 
> and parse out what we want?

The METAR's or in the WMO standard BUFR, not knowing what RAWS we are dealing 
with cannot answer, but would suspect BUFR.

> Then in the case of satellite imagery, do those just each get written as 
> separate images to the disk?  Is there any kind of metadata we can work with?

Yes, we carry all bands of the GOES E and W platforms. 

VIS 1km every 15 minutes for W-CONUS

..and so on.

To see a nice list please visit:


this catalog also provides useful metadata:



  For instance, can we get at the lat/long extent and resolution of the 
satellite imagery for mapping it later on our end?  (Which is what we would 
ideally be able to do).  You also mentioned decoders, and I'm not familiar with 
what those can do, so I've meant to start looking into those.

Depending upon how you plan to use the data the deocoders may or may not be 
applicable to you, most of our decoders
are designed for use in our applications McIDAS/GEMPAK/IDV..and also would be 
used to convert to netCDF, our format of choice
for many of our applications.

> So this is all new to us, and we'd appreciate some guidance as to what path 
> would suit us best.

What exactly are you wanting to do, we may be able to lend some insights based 
on our knowledge of the data.

It sounds like you are wanting to compare surface obs with satellite imagery in 
some manner, this should be quite workable
in many ways, can you provide any more details?

> I'd also like to at least run LDM on this side to see if we're even getting 
> anything yet.  But right now nothing at all is uncommented in the 
> pqact.conf...so I need to at least enable one of the FILE options.  And in my 
> ldmd.conf I have this request line:  request IDS|DDPLUS ".*" idd.cise-nsf.gov 
> .  So is that request line and regex sufficient to get at least a connection 
> test going once I enable a FILE in pqact.conf?

Yes, and you can also verify your connection by using the LDM utilty "notifyme":



notifyme -vl - -h idd.cise-nsf.gov -f IDS|DDPLUS

This will allow you to view the products in the IDS|DDPLUS feed as they become 
available across the network.

> Thanks for your help,
> Jared
Hopefully this will help get things started.


Jeff Weber
Unidata User Support

Ticket Details
Ticket ID: HKV-830940
Department: Support IDD
Priority: Normal
Status: Open