[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

20010726: 20010726: Radar mosaics on FNEXRAD feed

>From: Gilbert Sebenste <address@hidden>
>Organization: UCAR/Unidata
>Keywords: 200107261758.f6QHwP112136

>> Gilbert,
>> The mosaics are GRIB format (eg data on a grid) from the GEMPAK
>> products I am generating at:
>> http://motherlode.ucar.edu/unidata/images/nids/gdradr.html
>> There are no restrictions.
>> I insert them as GRIB format so that other packages than GEMPAK can
>> use them. They are created from the NEXRAD products on NOAAPORT
>> roughly every 6 minutes. The national product is about 6km. The
>> regional is about .9km. The regional product will be a floater
>> that gets moved around. You can generate your own mosaics with
>> GEMPAK or WXP...but thse will give many sites a change that don't have
>> the power or bandwidth to receive all the NEXRAD data cia IDD.
>Can you make the national grid 2KM? Or even 1 KM? Right now, I get a 48
>color, 1 KM resolution grid file from DTN. The files range from about
>200K when little is going on, to 900 K when all heck is breaking loose.
>Obviously, at 2 KM, it's 4 times less. Would you consider cranking it up
>to 2 KM resolution at least?

No. Thats too large a grid from the US. Thats 9x the number of grid points
as the 6km (eg three times as many grid points in each direction). 
For a floater file, I think 6km is adequate, and better than 
the 10km HAXA00 KWBC. But sites can generate their own at any resolution
with the software. 

>> Of course, we're busy preparing for workshops right now, so I haven't
>> had time to prepare announcements yet.
>> The details are that the GRID messages are:
>> center id = 60 (eg ncar)
>> subcenter id = 1 (since I create tham, I can call unidata #1!)
>> model number = 1 for national, 2 for regional
>> The grid is self described as #255.
>> The parameter I am gridding is the N0R NEXRAD product, and identifying this
>> as parameter #201 (for the center and subcenter above).
>> Of course GEMPAK has no trouble decoding this in the same way all the
>> other model grib data arrives. I'm sure that Dan can probably tell
>> you what you need for WXP to identify these GRIB products.
>Right. OK, let me know about the resolution...I would be more interested
>in using them if they were 2 KM or better. And perhaps some minor
>ground-clutter/AP control? Of course, I'm asking a lot for a freebie
>image...that 4 KM image probably pounds motherlode good anyway when it is
>making it!

The point here is this is a grid file. The end user is welcomed to apply
any function for clutter control, precip type computations, etc. depending
on their own needs and ideas about how to specify the algorithm.

> *
>Gilbert Sebenste                                                     ********
>Internet: address@hidden    (My opinions only!)                     ******
>Staff Meteorologist, Northern Illinois University                      ****
>E-mail: address@hidden                                 ***
>web: http://weather.admin.niu.edu                                      **
>Work phone: 815-753-5492                                                *
> *

Steve Chiswell

NOTE: All email exchanges with Unidata User Support are recorded in the Unidata inquiry tracking system and then made publicly available through the web. If you do not want to have your interactions made available in this way, you must let us know in each email you send to us.