This archive contains answers to questions sent to Unidata support through mid-2025. Note that the archive is no longer being updated. We provide the archive for reference; many of the answers presented here remain technically correct, even if somewhat outdated. For the most up-to-date information on the use of NSF Unidata software and data services, please consult the Software Documentation first.
> Full Name: Kyle DeLong > Email Address: address@hidden > Organization: Central Michigan University > Package Version: 5.4 > Operating System: Windows 10 > Hardware: 16GB RAM, i5-4690 with 3.5GHz > Description of problem: To Whom it May Concern, > > I am trying to use both the 2D and the 3D dewpoint depression parameter. > > Specifically, I am accessing the GFS 20km 2019_02_18_12z run and I am trying > to plot a color filled contour plan view chart at the 850mb level. The > default settings set up the chart in degrees Celsius and an interval of 5 > degrees. The chart is blank and when you middle click the mouse on the chart > to check the values, there are values that look like units of kelvin, not > Celsius (temperature values near 270). > > When I change the display units to kelvin, the values seem to be in Celsius > with values near zero and the chart is still blank. > > Is there an error, or am I using this parameter wrong? > > Thank you. > > Hi Kyle, The range of dewpoint depression is very different from the default temperature range. When you first create the color filled contour plan view display, you need to adjust the contour properties in the display control, change the max and min range. You also need to change the color table range to use the data value range. You don't need to worry about the unit, you can change the display unit and the IDV display can auto adjust. Yuan Ticket Details =================== Ticket ID: HTI-140412 Department: Support IDV Priority: Normal Status: Open =================== 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.