Where exactly are the cloud tops?
It's a question we ask on almost every IFR flight. Why? Because when you're in clear air, flying is easier, and you don't have to deal with ice. Take this flight for example:
So how do we figure out where the cloud tops are? We have three primary tools that we use:
1) The Graphical Area Forecast
With the Area Forecast out of production, we use its replacement: the Graphical Area Forecast. It uses the NOAA Rapid Refresh data model to forecast cloud coverage, bases, and tops.
While it's not the most accurate tool for forecasting cumuliform clouds, it seems to do pretty well with widespread stratiform clouds.
2) Color IR Satellite
We usually get a more accurate picture of what's going on with the Color IR Satellite overlay. This isn't a forecast, it's a picture of what's happening right now. And, while it shows the cloud coverage, it doesn't directly show the height of the tops. But it does show the temperature at the cloud tops.
When you combine the temperatures from the Color IR satellite with the Winds and Temperatures Aloft forecast, you can get a pretty good picture of where the cloud tops are. But there's one major problem: Color IR satellite can only see the highest cloud layer. If there's clear air below the clouds, you have no way of knowing.
3) Pilot Reports
Pilot reports are often the most accurate, but many pilots don't report cloud tops, only the cloud bases. Luckily we have quite a few pilot reports for this flight, with some top heights.
In the example below, an Embraer 175 reported cloud tops at 12,500' MSL, with light rime ice between 9,500' and 11,500'
Avoiding Ice
Our Cirrus SR-22 turbo is equipped with a TKS deicing system, and it's certified for flight into moderate known icing. But that doesn't mean that we ever want to stay in icing conditions.
By combining the Graphical Area Forecast, Color IR Satellite, and Pilot Reports, we're able to get a good picture of where the cloud tops are, and make sure that we can climb above them.
The best anti-ice system is clear air, and that's our goal almost every flight - climb through the clouds to get on top. Plus, when you're on top of the clouds, you just can't beat the view.
Have a cloud top story to share? Tell us about it in the comments below...
