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Hey Cory- > Thanks Don....now I'm trying to place 10m HAGL wind barbs over topography. I > have to select a formula to calculate wind speed and direction and running to > trouble with surface winds. I can either plot 10m HAGL winds however, it is a > 2d plot where I can only raise and lower the image. The other is the True > wind vector formula, however, that only allows selection of constant pressure > surfaces (from the Gempak file)...not 10m HAGL. Is this feasible? It's a little complicated, but will be easier in the next release. For now: - select the Misc->Any Field formula and the 3D Surface->Wind Barbs Over Topography and hit the Create Display button. - when the topography dialog pops up, select geopotential height @ surface - When the dialog pops up for "field", select the Grids->Make flow vectors from grid relative u and v data formula. - Next, select the 2D grid->u-component of wind @ HAGL and 2D grid->v-component of wind @ HAGL for u and v. That will give you a plot. A couple of caveats: - it will not plot the vectors at 10 meters above the topography but right at the topography surface. The 10 meters gets lost in the combination. - The barbs are plotted horizontally at the location of the grid point. If you underlay a topography, the barbs will cut through the surface. They don't end up draped over it. Streamlines will end up on the surface. > Next you guys should try to develop an app with IDV that allows users to kill > mosquitoes....man they are ferocious up here Maybe we could put a 3D hand in the IDV. ;-) Don ________________________________________ > From: Unidata IDV Support [address@hidden] > Sent: Tuesday, June 23, 2009 1:24 PM > To: Joshua C Demko > Cc: address@hidden > Subject: [Support #LZX-581713]: color shaded image over topography > > Hi Cory- > > Best to send these to address@hidden in case I'm not around. > > > Real quick question? I am trying to remember the steps to drapping a color > > shaded image over topography. Here are my steps... > > > > Select temperature @ HAGL > > Then under display select Color-Shaded image over topography under the > > display window... > > Under the field selector I choose Formulas, then Miscellaneous, then Any > > Field hit OK > > Then select 2d field (WRF gridded data) such as temperature > > > > Error dialog box pops up at that junction with the following error... > > > > topography units K must convertible with m or gpm > > Now I am able to do this same procedure only for the model terrain but no > > other Met field. I believe I remember the steps correctly. I am using IDV > > 2.7 beta 3. > > You need to select a topography (vertical units of m or gpm) for the > topography field. You've already selected the temperature field in the first > step. When the dialog pops up, select the 2D grid->geopotential height @ > surface (HGHT_NONE) field. It should show up as a topography field now in > 2.7 b3 so you don't have to use the Any Field any more. > > Don Murray > > Ticket Details > =================== > Ticket ID: LZX-581713 > Department: Support IDV > Priority: Normal > Status: Open > Ticket Details =================== Ticket ID: LZX-581713 Department: Support IDV Priority: Normal Status: Open