The hidden value of ForeFlight’s Imagery tab
Most ForeFlight pilots use the Airports and Maps tabs most often. That makes sense, because these two sections of the app have an incredible number of features that are useful for everyday flying. But that doesn’t mean the rest of the app can be ignored. In particular, the Imagery tab deserves more attention than most pilots give it – after some recent changes, it’s more valuable than ever.
Here’s how we use the page to do a solid weather briefing.
Understand the flow
Imagery has steadily grown over the years, adding a number of new graphical weather maps, but ForeFlight reorganized the entire page last year so it’s a lot easier to use now. There’s a loose top-to-bottom flow that mirrors the way you plan a flight: start with big picture weather maps and long range forecasts, then work down toward current observations like radar and PIREPs. If you start with this concept in mind, it’s easier to work through Imagery in a systematic way.
Big picture
Start with the big picture. Whether you’re flying VFR or IFR, it’s always smart to begin with a look at the major weather systems. Where are the highs and lows, the cold fronts and warm fronts? Where are these systems forecast to move? Use the Prog Charts product to answer these questions, and get an overview of major weather trends. If you know there’s a strong low pressure system to the west of your route, for example, that will influence how you look at satellite and icing forecasts later on. It will also influence how much you trust the text forecasts.
After a look at the Prog Charts, move on to the precipitation products: 6 Hr Qty of Precipitation and 12 hour Prob of Precipitation (or PoP). These are oddly-named charts, but they’re really valuable. That’s because, while moisture or precipitation doesn’t necessarily equate to bad weather, there’s often a correlation. In the winter, areas of precipitation often mean icing aloft; in the fall it might mean IFR conditions. Get a general sense of where the moisture is and where it’s moving (or not as the case may be).
The other benefit of these precipitation forecasts is that they stretch out far into the future. Whereas TAFs are fairly near term forecasts, the PoP forecast goes out to 7 days. That’s valuable if you’re planning the return leg of an out and back trip. Use it to get a general sense of the long term weather trends. In the image below, you’d feel pretty good about a flight from Dallas to Wichita. But Nashville to Pittsburgh would be another story.
The final piece of the “big picture” briefing is a look at convective hazards, which you can find in the last three maps in the first section (CONUS weather). This can be added to your knowledge of the precipitation areas to determine whether that precip is just rain or perhaps something a lot more serious. Again, the extended forecast product here goes out beyond 24 hours for good long range planning.
Ceiling and visibility
With that background in mind, the visual ceiling and visibility forecasts will make a lot more sense. These maps, based on the Model Output Statistics (MOS) forecasts, are ideal for VFR pilots. The forecast maps go well into the future, and offer a good look at areas of low ceilings or visibilities.
Forecasts aloft
Next it’s time to get a feel for the full three dimensions of the atmosphere. Specifically, ForeFlight offers forecasts for three conditions at altitude – winds, icing and turbulence. In particular, the icing forecasts have been significantly expanded in recent releases of the app, so you can get a detailed look at potential in-flight icing risks, by altitude and time. These products make it easy to plan not only your route, but the right altitude.
Observations
So far we’ve dealt with mostly forecasts – that is, predictions about what might happen. These are helpful, especially if your flight isn’t for a few days. But as you get closer to your time of departure, you need more real-time, more regional information – observations instead of forecasts. The three main observations in ForeFlight are satellite, radar and PIREPs. These are pretty self-explanatory, although we like to compare visible and infrared satellite images to get a sense for the vertical development of clouds.
A final tip
There is one last element we like to review before blasting off – METARs and TAFs. These are the most specific in terms of both timing and location. While many pilots go to the Airports tab to read these text weather reports, we like to view them on the Maps tab. You can tap on any airport and quickly read METARs, TAFs, Winds/Temps Aloft and even MOS forecasts.
But there’s an even better way: turn on airport-specific weather layers, like visibility or ceiling. The advantage here is that you get a great sense of regional or local weather patterns. You can read a METAR and find out that the visibility at your destination is 2 miles. But is that isolated to just that airport (maybe in a river valley) or are IFR conditions widespread?
Then add additional weather layers, like radar and PIREPs. Here you can pull all of the individual weather products together on one map, along with your proposed route. This is a great last minute check, and you can learn a lot with a single glance.
Your tips
This top down approach has served us well, and actually made us more disciplined about considering all available weather information. How do you approach a pre-flight weather briefing in ForeFlight? Any tips to share? Add a comment below.
Very good article. I’d like to suggest a follow-up. Most of my flights are local — within an hour or so of my home airport. So I’m one of those pilots who look primarily at the Airports and Maps pages for weather information. Most of the weather charts that are displayed in ForeFlight’s Imagery tab are not identical to those explained in books I have studied for test preparation. So, as a follow-up or series of follow-ups, I’d love to see detailed explanations of how to read and interpret ForeFlight’s Imagery, chart by chart. Thanks.