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Gempak Users, I have posted a new GEMPAK program "GPRCM" which will plot the Radar Coded Message bulletins in the NOAAport data stream. This program can be found in the nawips-5.4/contrib directory of the gbuddy ftp account for Gempak as gprcm.tar.Z. I will attatch the gprcm.README file from that directory at the end of this message. The RCM bulletins contain digitized radar reflectivity values as well as annotations including Maxtop heights, cell centroid motion, mesocylone and TVS locations. GPRCM can be used to plot single site and composite reflectivity maps with the capability to turn annotations and reflectivities on/off as needed. Since GPRCM is derived from GPMAP, GPRCM can be used in conjunction with other GEMPAK programs to create overlays including satellite and NIDS imagery products (Yes, you can overlay RCM echos on satellite images and annotate NIDS images with maxtop, tvs, mesocyclones and cell movement). A dithering feature has been added for allowing some method of transparency or echoes. Examples of using GPRCM, including LDM patterns, can be found at: http://www.unidata.ucar.edu/packages/gempak/examples/gprcm/ I have included a sample plotting script as well. To install gprcm, download the tarfile to your $NAWIPS directory, unpack with: zcat gprcm.tar.Z | tar cvf - Then build and install with: cd $NAWIPS/unidata/programs/gprcm make clean make all make install make clean Please address any questions or problems to address@hidden. Steve Chiswell Unidata User Support GPRCM is a version of GPMAP that plots Radar Coded Message (RCM) bulletins. For examples of the use and capabilities of this program, see the GEMPAK Examples www page: http://www.unidata.ucar.edu/packages/gempak/examples/ INPUT PARAMETERS MAP *Map color/dash/width GAREA *Graphics area PROJ *Map projection/angles/margins|drop flag SATFIL *Satellite image filename(s) RADFIL *Radar image filename(s) LATLON *Line color/dash/width/label/inc PANEL *Panel loc/color/dash/width/regn TITLE *Title color/line/title TEXT *Text size/font/width/hw flag CLEAR *Clear screen flag DEVICE *Device|name|x size;y size|color type LUTFIL *Enhancement lookup table filename STNPLT *Txc|mkc/mkt/mks/mkwd/hwfl|stnfil RCMFIL *Input source text file RADTIM *Valid Plot time {current or dattim} RADDUR *Time duration (min_prior to RADTIM) DITHER *dither level MESO *mesocyclone color/marker/size/width/hw TVS *tornado vortex signature color/marker/size/width/hw CNTR *Cell Centroid movement barb color/size/width MAXTOP *Maxtop color RADINFO *Radar status color ECHO *Plot radar echoes (0=None,1=PRCP,2=PRCP&CLAR) PROGRAM DESCRIPTION GPRCM is derived from the standard GEMPAK program GPMAP. The behavior is similar to gpmap, with the addition of reading Radar Coded Message (RCM) bulletins and optionally plotting radar echoes and/or annotations from the remarks included within the RCM bulletin. RCM bulletins contain digitized reflectivity values derived from the 2.2 x 2.2 nmi NIDS Composite reflectivity product over the radar area of coverage out to 248 nmi based on grid squares approximately 5.4 nmi on a side. The reflectivity intensity value for each grid box is determined by assigning the maximum value of all Composite Reflectivity boxes whose centers are contained within the grid square. The RCM message comprises 9 intesity categories as follows: Code Color Plotted (Precip mode) 0 ND 1 15-30 dBZ 23 2 30-40 dBZ 22 3 40-45 dBZ 21 4 45-50 dBZ 20 5 50-55 dBZ 17 6 >= 55 dBZ 15 7 data beyond 124 nmi that are above threshold 8 data beyond 124 nmi that are below threshold RCM data within a user specified time range are plotted. RCMFIL is the RCM data file. Bulletins with radar observation times in the RCM file will be plotted if the observation time is within the range specified by the starting and ending times. RADTIM (current or dattim) specifies the ending time for accepted data. RADDUR is the number of minutes prior to the ending time to begin accepting data. DITHER is used to specify the plotting behavior of the reflectivity intensities. A value of 0 specifies no dithering, the grid box is completely filled. Values 1-4 increase the number of dither points per grid box, approaching an increasingly opaque value. Dither can be used to overlay image data with radar reflectivity in order to simulate transparency. A dither value >= 5 will outline the grid box. MESO specifies the color/marker/size/width/hw for mesocyclones to be marked. A color value of 0 is used to turn off mesocyclone plotting. Marker attributes behave as MARKER for other plotting programs. TVS specifies the color/marker/size/width/hw for tornado vortex signatures to be marked. A color value of 0 is used to turn off TVS plotting. CNTR specifies the color/size/width for Cell Centroid movement barbs (knots). A value of 0 is used to turn off centroid plotting. MAXTOP specifies the color for cell top annotations (feet). A value of 0 is used to turn off cell top annotations. RADINFO specifies the color for radar site operational status annotations. NA, data not available; OM, out for maintenance; NE, no echoes. ECHO specifies whether to plot the grid box intesities. A value of 0 specifies no plotting of echoes; 1 specifies plotting only those echoes from radars in precipitation mode; 2 specifies plotting of echoes from radars in both precipitation and clear air mode. GPRCM utilizes the nexrad.tbl station table to determine the radar location (not all RCM bulletins contain radar location as of Nov. 1999). The radars listed in the station table are also used to determine which locations are missing (Not Available: NA). EXAMPLES 1. Draw a Lambert Conformal map of the US. Display RCM data from the file rcm.dat. Plot radar observations for the past 60 minutes. Display the echo intensities (no dithering), maxtop values in yellow, and radar status in red. Do not plot mesocyclone, or TVS locations. Plot the cell centroid motion barbs in white. GAREA = us PROJ = str/90;-105;0 SATFIL = RADFIL = LATLON = 0 PANEL = 0 TITLE = 1/-1/Radar Summary TEXT = 1.3/22/1/hw CLEAR = yes DEVICE = xw RCMFIL = rcm.dat RADTIM = current RADDUR = 60 DITHER = 0 MAXTOP = 5 RADINFO = 2 MESO = 0 TVS = 0 CNTR = 1/1/1 2. Overlay the IR satellite imagery with RCM data for the US west coast. Use a DITHER value of 2 to for moderate transparency. Plot the radar CLRBAR horizontally above title. Satellite CLRBAR will be vertical along the left side of the image. GAREA = ca- PROJ = sat SATFIL = $SAT/GOES-10/4km/IR/IR_991108_1600 RADFIL = LATLON = 0 PANEL = 0 TITLE = 1/-1/Satellite and Radar Composite TEXT = 1/22/1/hw CLEAR = yes DEVICE = xw RCMFIL = rcm.dat RADTIM = current RADDUR = 60 DITHER = 2 MESO = 0 TVS = 0 CNTR = 0 MAXTOP = 0 RADINFO = 0 ECHO = 1 CLRBAR = 1/h/cc/.46;.06 ERROR MESSAGES [GPRCM -1] Fatal error initializing TAE. [GPRCM -2] Fatal error reading TAE parameters. [GPRCM -3] Fatal error initializing GEMPLT.