Liz, This is due to a quirk in Ferret's 2-dimensional plotting.  Take a look at this FAQ, which is about exactly this question: http://www.ferret.noaa.gov/Ferret/FAQ/custom_plots/time_series_overlay.html Your original script works if you redefine your time axis t2 as ` define axis/t="1-mar-2001":"10-mar-2001":24/units=hours t2` Ansley Manke Elizabeth Dobbins wrote: ```Hi; I've gotten 2 answers already! Jean Newman suggested define 2 identical viewports and using one for the shade plot and one for the overlay. Mick Spillane suggested adding a T0 to the 2nd time axis: define axis/t="1-mar-2001":"10-mar-2001":1/t0="28-feb-2001"/units=days t2 Then it works fine in the example, but still not quite in my more complicated problem. Still I think he's right when he suggested that the overlay is simply offscale somewhere, so I'm going to follow up on that idea. Liz On Thu, 14 Oct 2004, Elizabeth Dobbins wrote: ``` ```Hi; I'm trying to overlay a line plot of surface mixed layer depth over a shade plot of mixing coefficient. It works OK if I have a simple time axis, but if I try to regrid to a calendar time axis, the overlay doesn't work. Here's a simple example that recreates the problem: ! define the axes def axis/t=1:10:1 t1 define axis/t="1-mar-2001":"10-mar-2001":1/units=days t2 define axis/z=1:100:1 z1 ! create a couple variables to plot let varz= 0*t[gt=t1]+z[gz=z1] let dep = {10,20,30,40,50,60,70,80,90,100} ! This one works shade varz plot/over dep[gt=t1@asn] ! This one doesn't shade varz[gt=t2@asn] plot/over dep[gt=t2@asn] I've tried all sorts of things to fix dep, like specifying the l range and defining an intermediate variable, but nothing I've tried works. Maybe someone else can find a way? Liz ********************* Elizabeth L. Dobbins Research Scientist JISAO/PMEL phone: (206) 526-4581 "Various forms of jiggery-pokery were used to suit horses to courses." -- Michael Burleigh ``` ``` ********************* Elizabeth L. Dobbins Research Scientist JISAO/PMEL phone: (206) 526-4581 "Various forms of jiggery-pokery were used to suit horses to courses." -- Michael Burleigh ```