In this lesson we'll discuss product layering and time match basis. 

Let's start off by loading three products: a satellite product, some surface obs, and then some lightning data. So let's make sure we're on the WFO scale and go to the satellite menu. And select visible. Next let's go to the obs menu and select surface plot. And finally, let's go back to the obs menu and go down to lightning, over to NLDN, and let's load the 15-minute plot. Before we proceed, let's go ahead and increase the magnification to see little text a little bit better. So let's go to mag and select 1.5. 

Okay, now we see our products are stacked on top of each other. Let's go ahead and see if we can move them up and down and see what happens. So let's right click and hold on the satellite product, GOES 14 visible imagery, and select move up. So it looks like the state and county boundaries map is now hidden underneath the satellite products. So not only are the products in the stack linked, but so are the maps. So let's go ahead and try to move the satellite product up some more. Right click and hold and select move up. So it looks like our surface obs are now hidden underneath the satellite product in addition to the state and county boundaries map. And let's try to move it up some more. Select right click and hold and select move up. 

So now we can see that all our products are now effectively hidden underneath the satellite product. And we don't really want to do that. I just wanted to show that for demonstration. So let's go ahead and move it back down. Right click and hold on the satellite and select move down. Right click and hold on satellite again and select move down. And finally let's recover our state and county boundaries map by right clicking and holding on the satellite product and selecting move down one final time. There we have it. 

Since we loaded the satellite product first, that means the time match basis is automatically set to the satellite product. And we can verify that by looping through the data and noticing that all the other products update only when there's a new update in our satellite product. We can also verify that with the asterisk that we see next to the satellite product. Now we can also set time match basis to another product. So let's go ahead and try to set it to the 15-minute lightning product, which is the orange product in the product legend. Let's right click and hold on it and select time match basis. As you see the asterisk now changes place to the 15-minute lighting product. And let's verify by looping through the data and noticing that all the other products are now updated only when there's a new update in the lightning product. And time match basis is gonna be very important. For example if you have radar data and satellite data loaded. Well if you set the time match basis to satellite data, you'll only get a new radar scan every 10 or 15 minutes, when you really need one every 3 minutes, for example. So make sure to set the time match basis to the correct product.