In this video we're gonna practice using the FFMP Basin Trends and interpreting the all hour graphs and look at some downstream traces and explore different ways to interact with the D2D display and FFMP. 

So let's go ahead and we'll clear our display. If you've had it loaded just to clear this out. Start at WFO scale. Frame count doesn't matter if it's 1 or 12 because we're gonna go straight to FFMP this time and load the DHR display. So when the table loads one of the first thing I like to do is right-click on top of the FFMP Basin table, select always on top. So that I don't have to fight my display, and I'm toggling back and forth between the D2D display and the basin table. We're gonna go ahead and select, let's go ahead and select ratio as the D2D display. And we'll go all and only small stream basins as a layer. And then we can adjust our slider bar. Probably go to a 3-hour accumulation. 

Alright now you can see FFMP is taking some time loading down here. So you'll see a lot of different messages as it's loading stuff into the first time for its display. So one of the things that we can do right off the bat with FFMP is just have a quick look at where have we exceeded flash-flood guidance. And for a different duration, say well for a 1 hour duration, for a 3 hour duration, where have we exceeded flash-flood guidance? And so we see these areas anywhere where it's greater than 100% is where we've exceeded flash flood guidance for a ratio product. We can sort the table by ratio here. But let's say so we've got 1.24 inch difference, you know over flash flood guidance. But what's happened to get us to this point? That's what we want to know is what's the time trend been of the precipitation. Is it still raining there? Or what's going on at that location? 

So when we kind of zoom in and we see the the basin that we're investigating, we can right-click on the basin name her. And again, we're at three hour duration and it's going to launch a basin trend. So the basin trend is a convenient graph, that's gonna allow us to look at a whole bunch of different hours. And this is the all hour plot to start out with. The first thing you want to get oriented with is what's the instantaneous precip rate trend been relative to now? So time T equals zero is down here on the lower left. And it's hours before 23:37, which is the time that was in our FFMP basin table. So is it raining right now? If it's raining right now I better have an instantaneous precip rate greater than zero at time T equals zero. So yes I do. I've got an instantaneous precip rate that gets 1.79 on my table off the screen here is what it what it displays. So it's raining right now. This dot is the instantaneous precip rate. That's the basin averaged reflectivity has been converted to a rain rate, that's an instantaneous rain rate. So we can look at relative to now, each one of these dots represents a volume scan that was you know in the past. There's the volume scan trace of the of the radar scanning over the last few hours here. 

So we can see in the last 15 minutes the instantaneous precip rates have been up around three inches per hour at each one of those observations. There's a little bit of weakness in between where the rates drop down to almost a half an inch per hour. But it was about an hour ago, the rates were four inches per hour for you know good 15, 20 minutes. And then once we got about an hour and a half ago was it raining? Well the instantaneous precip rate was just about zero. Two hours ago was it raining? The instantaneous precip rate is zero so no it wasn't. And so this kind of gives us a sense for what's been the evolution of the accumulation that's happened, you know over the last few hours here. And what are the instantaneous precip rates been at each volume scan? So that's the first thing. 

The second thing is where you have to start transitioning your thinking with these graphs. They can be a little bit confusing the first time you're looking at them, because it's hours before this. And now we're gonna go into a qpe accumulation. So I always like to make a fundamental shift here. When I start looking at accumulation, I'm thinking accumulation and duration rather than you know hours relative to now in a negative sense. So for each one of these instantaneous precip rates, you take that instantaneous precip rate, multiply it by the volume scan duration and you're going to get a little precip accumulation for that segment in between volume scans. So for each one of these above zero instantaneous precip rates, we're accumulating slightly more precip as we accumulate backwards from now. As the rates go down, the the accumulation kind of flattens out and as it spikes up again, we get really steep accumulations occurring when we have these four inch per hour rates. And then all sudden the one hour accumulation, how much rain did we get? Well we go up here at one one-hour relative now. In the last hour, it looks like we've accumulated about 2.75 inches. In the last hour and a half how much precip did we accumulate? About 3.6 inches. Over the last two hours how much precip did we accumulate? 3.6 inches. Okay well, why is that the same? Why is that accumulation not changing? Because the instantaneous precip rate is zero. We're just accumulating zero. So this graph starts to make more sense when you think of the instantaneous precip rate relative to now in a negative sense. And then think of these accumulations as durations. A one hour duration accumulation 2.75. Two hour accumulation 3.6. Now the data truncates here at about two and a half hours, two and three-quarters hours, and that's unique to this data set. But we're gonna use that to show what the gaps in the data look like. So normally you'd have more, more continuous precip accumulations. But in this, in this data set it kind of ends off at about three hours. 

So we've looked at rate. We've looked at qpe. Now let's look at the guidance So if we toggle that on, yours could have been off to start with. Then each one of the one, three, and six hour flash flood guidance for this Basin average quantity, that thing that we were looking at in Lesson one, is gonna be plotted here. So what's the one hour flash flood guidance from the RFC's for this basin average? It's about two inches. What's a three hour flash flood guidance? Is about 2.4 inches. And then a six hour flash flood guidance is about three inches. And then we can interpolate in between those. So if I want to see in this graph have I exceeded flash flood guidance for a one hour duration? Well RFC's say two inches is all it takes in an hour to two to be the threshold for flash flooding and the precip accumulation is 2.75 inches. So I'm about three-quarters of an inch over flash flood guidance, and I can visualize that clearly for one hour. We want to look at two hour flash flood guidance, compare that to an accumulation. Well I don't have the observation. But if we, you know kind of take an average of the one and three, two-hour flash flood guidance is about 2.2 inches, and I've got 3.6 inches of accumulation. So it's like a 1.4 Inches over flash flood guidance for a two hour duration. So you can basically see anywhere where this black line with the dots for each each accumulation, you know for that duration for that period, when that exceeds the flash flood guidance, and that's higher than that then I'm exceeded flash flood guidance. And you know, the greater the difference the higher the flash flood threat. So this is a really powerful way of looking at multiple durations. And normally you have these filled out out to six hours and beyond. And so you're able to really synthesize a lot of different hours of data, and look at, you know there's a training signal where I had accumulations over two hours or four hours. You know, when did I exceed flash flood guidance the most? For what duration? You can answer that with the all hour graph. 

Now you can also go in here and come to the same kind of conclusion looking at the one-hour accumulation, which is valid 23:37 over here. But it just says, start running the accumulation from zero at 22:37. And then see what the instantaneous precip rate? How that accumulates over that last hour? And then it plots the flash flood guidance for two hours, or for one hour at about two inches. So you can do that for one hour. Start the running total three hours ago to see when did the precip fall? So it can take a little used to getting used to the the all hour graph. But you can also use these others, but you have to step through multiple, multiple radio buttons to do that. Whereas the all hour graph, you can just look. And after you get used to it you can see one, three ,six right away, move on to the next Basin. And it really accelerates your analysis process of lots of basins.

Another thing we can do with this is relatively new and that's, let's bring in the average recurrence interval information and see okay, if we treat this as a source and overlay it, which it's not a flash flood source. But it does tell us a little bit about precipitation frequency. What's a one-year recurrence interval or it has a hundred percent chance of happening in a given year? So for a one hour duration, that's gonna be about well 1.4 inches, something like that. And we've got 2.75 so, this is not just your Yearly kind of recurrence of an average precip for a one hour duration. If we look at kind of a three hour it'd be almost closer to two inches. And we see we've probably accumulated about 3.6 inches for that duration as well. So you know we've exceeded a lot of durations in terms of the comparison to the average recurrence interval. We want to look at the ten-year recurrence interval. So if I had a 10% chance of happening in any given year. That's about 2.4 inches, and we've got 2.75. So what we're getting closer to a you know one in every ten year kind of precipitation accumulation for a one hour duration. And same can be said for about three hours. Now six hours if we extrapolate this out here it's probably not quite to that level. So you can get you know 3.6 inches in  six hours every ten years. But for this one we're seeing, we've even exceeded the 10-year recurrence interval for one hour duration. So let's check out a hundred-year, you know one percent chance of that event happening in a given year. That would be four inches in one hour. It would be a real kind of real rare event. So again we can kind of start piecing together, not only how much precip is accumulated according to this source, but what's the rarity of that precipitation accumulation? And this display in the all hour graph is really a fast way to be able to just kind of step through and see okay, yeah, what am? I'm probably more like a 10, maybe 25 year. I've exceeded 25 in here. So close to a 50-year recurrence interval for you know something a little over an hour. So this average recurrence interval data set really does give us another bit of information from our gauge climatology to just start to get more familiar with how significant are these precipitation accumulations to get more in tune with what's relevant for your CWA. 

So that was the Basin trend and it was the all hour graph. So that we could launch that with a right-click on any Basin name. So we just click on any Basin in here and right click on it, and we display it. One of the things I was talking about before is when we do that, there was some missing data after about two hours. So let's go to one hour and see what the gap in the data does. And we see that there's a, the gap is listed as zero here on the FFMP table at one hour. When we go to three hours, we see that over that three hour period is about twenty minutes that's missing here. That once you have missing data, for some reason your radar goes down or the product quits ingesting, then once this is nonzero, you know you're missing data. So if we go to six hours, it's really gonna stand out because we've got a lot of missing data here. And see how that gap turns red, that's three hours of missing data. So whenever you see gaps that are not zero, that means you're missing precipitation accumulations in the duration that you've requested. So it's an artifact of this case, doesn't happen very often, but at least it allows us to kind of see what that looks like. So if you ever see that in operations you need to take it seriously and go check out, why is my, why am I missing precipitation data? 

Alright, so we've looked at the Basin trend, and we've launched it from right clicks on the menu. Now a more powerful way to do this, because it can take time to find anything in that table. Sure you can go to county level displays and then have it paired down and look for names with you know a hundred basins instead of a thousand. But what's even more powerful is to use the click menu to configure, what is my right-click in the D2D gonna do? And I could specify that to launch a Basin trend. So I've selected click Basin trend. And if I want to interact with the D2D display, I have to make the product legend editable. This is the same for Warngen. It's same for baselines. If you have Warngen and FFMP loaded at the same time you're gonna have to toggle between editable so the applications know which resource am I going to interact with when I interact with the display. So to make this editable, there's two ways of doing it. I can middle click on the product legend text for FFMP. And you see that just changed it to editable. If I right click and hold I can check or deselect the checkbox, that's the editable checkbox. But I prefer just a middle click on that product legend, make it editable after setting my click. And if I want to find out what this Basin is right here, give me a basin trend for that, I just right click on it and there she blows. It's real handy for if I'm looking out over here for this Basin has less precip, right click on that. I can launch any Basin trend from just a simple right-click on the display. Now this is a lot more powerful. Basically opens up, you can surf the all hour displays and be very comfortable with where's the real flash flood threat? And then be able to look for particular points in space that you know of in your cities or other areas, I can just launch it from directly from the display. That's much easier to do than actually trying to find things in the names and then right clicking on the menu names for the basins. So that's one thing we can do with the click. The other thing we can do with the click is let's go ahead and move this back to three hours. 

And if we go to the click menu, you can say well, I want to know what's gonna happen to this water after this rainfall accumulates? Where's the runoff gonna be? So I'm gonna select downstream Basin trace. Now this is going to use the small stream basins link. And let's go ahead and look for some of these basins. We'll kind of zoom in and and see a particular basin on here. Let's choose this guy over on the eastern end of this area of exceeded flash flood guidance. If I make my legend editable and then right-click on that basin, it's gonna go to the stream links file and it's gonna connect every basin downstream and it's gonna hatch that area. Now you really can't read it very well with the default coloring so you can right-click on the product legend and go up here to change the up and downstream color to something like a red. Another trick I like to do is do a control eye for the image properties and then we could reduce the brightness so that we can see the product overlays. Get that out of the way. And we could see in here that this Basin we right clicked on it's going to be downstream of, this is the basin downstream. And so the runoff is going to be to the north. So we can click on any Basin in here and visualize where is the runoff gonna be. So if we want to expand our flash flood warning polygons by a couple of basins to account for the the drainage process that happens once water is accumulated, we can do that. And then if we just keep clicking around we'll see that this must be a ridgeline right in here where it separates water flowing off to the north from water flowing off to the southeast. And this is really another powerful way to use some of the GIS capabilities in FFMP and in AWIPS. 

So about the only thing we didn't really cover were the virtual gauge basins and again, you can launch base and trends for those. There's a vgb checkbox which on a live system. If you're getting hourly PP and hourly, PC observations in your hydro tables, when you click that it's gonna give you a time trend of the actual gauge accumulation so you can compare to your your radar based estimations and then look for biases and how those compare. That's not gonna work in case review in WES 2 Bridge, requires more archived data sets and more capability. But at least would point it out that that's another option to use in your Basin trends for any of these purple basins which are virtual gage basins. But that's more advanced FFMP use even than just the all hour graph and just the basics for the downstream, the downstream basin trace. 

So that's gonna wrap up our section on FFMP we looked at the first lesson looked at kind of the horizontal plots and just doing simple display of where have I exceeded flash flood guidance? But the real power in FFMP gets to be in these Basin trends where you can look at how much rain falls. When did the rainfall happen? And how much over flash flood guidance? And put together the timing of the of the evolution as well as dynamically launching these trends and the downstream traces from interacting with the D2D display. If you just remember your click menu and remember to middle-click or make that text legend editable to always interact with the FFMP resource with your right click.