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[GEMPAK #YTR-838531]: Canadian RADAR data file

> Thanks Chiz.
> 
> Do you want me to get permission to set up a LDM that can feed you the
> real-time files to test if they are of interest to the community?

I think that would be great.

> 
> The values in the files are intensity in millimeters per hour, not dBZ and
> are supplied that way by MSC.

I do recall you mentioned that. A good reason for gridding them separately then.

> 
> The values are derived from these two formulae:
> 
> [1] Z = 1780 R ** 2.21 (snow) Sekhon and Srivastava (1970)
> [2] Z = 295 R ** 1.43 (rain) Richards and Crozier (1983)
> 
> The data begins arriving as snow in early December and switches back to rain
> in April.  MSC usually tell us when they change the values ahead of time,
> sometimes not.
> 
> I will work with you source for a few days and start producing some images.

Let me know if hings do not "line up" with what you expect. I'll add this 
program
to the distribution once its been kicked around for a while.

Steve Chiswell
Unidata User Support






> 
> Thanks again.
> 
> Stephen Sinnis
> Pelmorex Media Inc
> T. 905.829.1159 x1379
> F. 905.829.5800
> -----Original Message-----
> From: Unidata GEMPAK Support
> [mailto:address@hidden]
> Sent: Monday, November 06, 2006 4:28 PM
> To: address@hidden
> Cc: address@hidden
> Subject: [GEMPAK #YTR-838531]: Canadian RADAR data file
> 
> Stephen,
> 
> Attached is a composite plot of the canadian radars you provided and the US
> level III data for the same time of 061104/1530.
> 
> I found in your data a few outlying values (such as 92, 453, etc). Those
> values really are in the data, but I don't know how to interpret them, or
> compare these with dBZ levels in the Level III products, so gridding them
> together using the MAX value may give strange results (asside from the fact
> that your values are 1.5km cappi).
> 
> Instead, I gridded your data to a separate grid file, and then took the max
> value in the gdplot2 output function (but can process that after the fact
> rather than in the same grid file).
> 
> I have posted the source for the gdradrc program as a tar file:
> http://www.unidata.ucar.edu/downloads/gempak/nawips-5.9.4/source/canadian_ra
> dar.tar.gz
> 
> Using your ascii data in a $RAD/cradar tree and a datatype.tbl entry of:
> CRADAR       $RAD/cradar/%SITE%/%PROD% %PROD%_YYYYMMDD_HHNN
> (note you will find that entry in the datatype.tbl file in the tar file).
> 
> I also created a cradar.tbl file (in that directory and commented out one
> duplicate station from your list (Marble Mountain).
> 
> The program took 5 seconds to grid your 30 stations to a 1,615,000 point
> grid:
> GRDAREA  = 44;-128;47;-48
> PROJ     = lcc/50;-110;50
> KXKY     = 1700;950
> GDPFUN   = n1r
> GDFILE   = 20061104_radr.gem
> RADTIM   = 061104/1530
> RADDUR   = 30
> RADFRQ   =
> CPYFIL   =
> STNFIL   = cradar.tbl
> MAXGRD   = 1000
> NDVAL    = -9999
> GEMPAK-GDRADRC>
> 
> Note that the LLMXTG size in my 5.9.4 distribution will accomodate 1,679,940
> points.
> 
> I then plotted the 1530Z Canadian and 1531Z US radar files in gdplot2 with:
> GDFILE   = 20061104_cradar.gem+20061104_usradar.gem
> GDATTIM  = 061104/1530
> GDPFUN   = smax(miss(n1r,n0r^061104/1531+2),miss(n0r^061104/1531+2,n1r))
> TYPE     = z
> FINT     = 0;1;2;3;4;5;6;7;8;9;10;15;20;25;30;35;40
> FLINE    = 0;30-7
> GAREA    = 44;-128;47;-48
> IJSKIP   = y
> PROJ     = lcc/50;-110;50
> STNPLT   = 5/1/1/1||cradar1.tbl#1
> 
> If you would like me to post a binary for this program let me know so you
> can take a look.
> 
> Depending on data restrictions, you may be able to redistribute a grid of
> data you produce if not the original ascii data files, but as you mentioned,
> it will be worth exploring down the road. In the mean time, let me know if
> you find bugs, etc (and or more active weather to test againast ;-)
> 
> Steve Chiswell
> Unidata User Support
> 
> > Hi Steve.
> >
> > Thanks very much for the plot.
> >
> > I tar gzipped up all the Canadian radar files between 14 and 16 UTC
> > SAT 04 NOV 2006, and gave the file ecrad.tar.gz to Tom - I did not
> > what to e-mail it.  Tom said he put it on a scratch disk?
> >
> > Here is a sample file name and path:
> > ./WBI/N1R/N1R_20061104_1502
> >
> > Each file inside ecrad.tar.gz is also gzipped, but does not have the ".gz"
> > extension.
> >
> > Some files are of zero length, due to someone requesting from EC that
> > files be sent every ten minutes, whether or not the RADAR was actually
> > collecting data. - NOT ME.
> >
> > Here are the table entries that I made up for the Canadian RADAR sites
> > that I put in nexrad.tbl
> >
> > WBI      071632 BRITT/SUDBURY                    ON CN  4580  -8053   475
> 24
> > MSC
> > WGJ      070001 MONTREAL RIVER HARBOUR/SS_Marie  ON CN  4723  -8452   520
> 21
> > MSC
> > WHK      070002 CARVEL/EDMONTON                  AB CN  5362 -11415   782
> 0
> > MSC
> > WHN      070003 JIMMY_LAKE/COLD_LAKE             AB CN  5490 -10997   637
> 21
> > MSC
> > WKR      070004 KING_CITY/TORONTO                ON CN  4397  -7957   360
> 27
> > MSC
> > WMB      070005 LAC_CASTOR/CHICOUTIMI            QC CN  4858  -7067   884
> 18
> > MSC
> > WMN      071626 McGILL/MONTREAL                  QC CN  4542  -7393    50
> 25
> > MSC
> > WSO      070008 EXETER/LONDON                    ON CN  4337  -8138   303
> 21
> > MSC
> > WTP      070009 HOLYROOD/ST_JOHN_S               NF CN  4733  -5313   122
> 12
> > MSC
> > WUJ      070010 ALDERGROVE/VANCOUVER             BC CN  4902 -12249    91
> 12
> > MSC
> > WVY      070011 VILLEROY/QUEBEC                  QC CN  4642  -7193   100
> 18
> > MSC
> > WWW      070012 SPIRIT_RIVER/GRANDE_PRAIRIE      AB CN  5541 -11914  1015
> 30
> > MSC
> > XRA      070013 RADISSON/SASKATOON               SK CN  5252 -10744   530
> 12
> > MSC
> > XBE      070014 BETHUNE/REGINA                   SK CN  5057 -10518   579
> 12
> > MSC
> > XFT      070015 FRANKTOWN                        ON CN  4504  -7611   122
> 18
> > MSC
> > XWL      070016 WOODLANDS                        MB CN  5016  -9778   270
> 12
> > MSC
> > XME      070017 MARBLE_MOUNTAIN                  NF CN  4893  -5783   540
> 0
> > MSC
> > XGO      070018 GORE/HALIFAX                     NS CN  4510  -6370   210
> 18
> > MSC
> > XLA      070019 LANDRIENNE                       QC CN  4855  -7781   394
> 24
> > MSC
> > XAM      070020 VAL_d_IRENE                      QC CN  4848  -6760   710
> 12
> > MSC
> > XSM      070021 STRATHMORE/CALGARY               AB CN  5121 -11340   968
> 12
> > MSC
> > XSI      070022 MOUNT_SICKER/VICTORIA            BC CN  4886 -12376   700
> 27
> > MSC
> > XBU      070023 SCHULER                          AB CN  5048 -11020   863
> 12
> > MSC
> > XFW      070024 FOXWARREN                        MB CN  5055 -10110   540
> 12
> > MSC
> > XMB      070025 MARION_BRIDGE                    NS CN  4595  -6020   100
> 12
> > MSC
> > XDR      070026 DRYDEN                           ON CN  4987  -9280   410
> 0
> > MSC
> > XME      070027 MOUNT_MARBLE                     NF CN  4893  -5783   540
> 12
> > MSC
> > XNI      070028 LASSETER_LAKE                    ON CN  4885  -8901   457
> 24
> > MSC
> > XSS      070029 SILVER_STAR                      BC CN  5033 -11907  1880
> 24
> > MSC
> > XPG      070030 PRINCE_GEORGE                    BC CN  5361 -12293  1118
> 0
> > MSC
> > XNC      070031 CHIPMAN                          NB CN  4622  -6570   100
> 27
> > MSC
> > XTI      070032 TIMMINS                          ON CN  4930  -8180   244
> 19
> > MSC
> >
> >
> > Cheers.
> >
> > Stephen
> >
> > -----Original Message-----
> > From: Unidata GEMPAK Support
> > To: address@hidden
> > Cc: address@hidden
> > Sent: 11/3/06 3:15 PM
> > Subject: [GEMPAK #YTR-838531]: Canadian RADAR data file
> >
> > Stephen,
> >
> > I was able to convert your data to a grid by adapting the gdradr
> > program.
> > This will use a series of individual station files and composite them
> > into a single grid for display. It takes about 0.5 seconds to convert
> > the file you provided me which comprises 8538 lat/lon/value groups.
> > For 30 stations or so, this would only take as long as it takes to
> > read the data from the disk files.
> >
> > The pattern I plotted is basically a ground clutter pattern. At this
> > point, I would be helpful if you could provide a set of your files for
> > several stations where some weather is occuring so I can test things
> > out. Otherwise, I can send you the routine as I have it now so that
> > you can verify point locations.
> >
> > I have attached a plot based on the data you sent me.
> >
> > Steve Chiswell
> > Unidata User Support
> >
> > >
> > > Hi.
> > >
> > > I am trying to quickly import the Canadian Numeric Ascci RADAR data
> > files
> > > into either a GINI or GEMPAK grid file for use in GEMPAK.
> > >
> > > I have included a sample file, and would appreciate any help or
> > suggestions
> > > in how to proceed.
> > >
> > > Thanks
> > >
> > > Stephen Sinnis
> > > The Weather Network
> > >
> > >
> > >
> >
> >
> > Ticket Details
> > ===================
> > Ticket ID: YTR-838531
> > Department: Support GEMPAK
> > Priority: Urgent
> > Status: Closed
> > <<wkr.gif>>
> >
> >
> 
> 
> Ticket Details
> ===================
> Ticket ID: YTR-838531
> Department: Support GEMPAK
> Priority: Urgent
> Status: Closed
> 
> 


Ticket Details
===================
Ticket ID: YTR-838531
Department: Support GEMPAK
Priority: Urgent
Status: Closed