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James, The velocity couplet actually display quite differently as tilt angle is varied. The 2230 file I have shows available velocity tilts as: TILT=list 2: elev 0.490581 3: elev 0.489972 4: elev 0.483398 6: elev 1.494262 7: elev 1.497549 8: elev 1.498645 9: elev 2.389282 10: elev 2.373047 11: elev 2.381081 12: elev 3.394079 13: elev 3.390137 14: elev 3.388658 15: elev 4.274471 16: elev 4.262695 17: elev 5.988945 18: elev 9.900442 19: elev 14.601773 20: elev 19.509041 When I use TILT=.483398 (eg the lowest), I get your plot. When I use TILT=.489972, the green is just a small portion, and when I go to .490581 the green is gone. So, that seems to be the data that is realy in the file, and seems to be consistent in that it doesn't just disappear from one tilt to the next, but there is some trending upward. Have you investigated this through various levels at the times before and after the 2230Z frame? Steve Chiswell Unidata User Support. >From: James Murakami <address@hidden> >Organization: UCAR/Unidata >Keywords: 200409241716.i8OHGQnJ028523 >--Mumble_of_Moles_976_000 >Content-Type: TEXT/plain; charset=us-ascii >Content-MD5: lgFXZDSWvuvcn8Zk9K4xuw== > >Hi. When I run gpnexr2 (version in GEMPAK5.7.2p2) to view >a velocity plot, the image doesn't look quite right. That >is, part of the image that should have positive speeds >are negative (green color). Compare the velocity couplet >in the LCH.gif (taken from level III data) versus the >KLCH.gif (level II data). The left side of the couplet should >be in all "warm" colors. I know the magnitude scale is >different for the two images, but orange is positive on both >scales. Also, green is negative for both. > >The plots I've attached were run from the source version for >Solaris. I got the same results when running on a (binary) linux >version (plots not included). > >I also attached copies of the setting I used to plot in gpnexr2 >as well as the level II radar file (in case it turns out the >file is at fault). > >As always, thank you for your assistance. > >James > >---------------------------------------------- >James Murakami >Staff Meteorologist/Student Affairs >Department of Atmospheric and Oceanic Sciences >University of California, Los Angeles >405 Hilgard Ave. >Los Angeles, CA 90095-1565 > > > e-mail: address@hidden >telephone: 310-825-2418 > Fax: 310-206-5219 >----------------------------------------------- > >--Mumble_of_Moles_976_000 >Content-Type: TEXT/plain; name="gpnexr2.nts"; charset=us-ascii; x-unix-mode=06 > 44 >Content-Description: gpnexr2.nts >Content-MD5: R9/jSX918NZP+ySg+3QUdw== > >MAP 18//2 > >GAREA dset > >PROJ rad > >RADFIL NEXRII|KLCH > >LATLON 0 > >PANEL 0 > >TITLE 31/-2 > >TEXT 1 > >CLEAR YES > >DEVICE xw > >LUTFIL default > >IMCBAR 31/V/LL/.005;.05/.85;.01|.7/1/1/hw > >TILT 0 > >RADPARM vr > >RADTIM 040923/2229 > > > -- 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.