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An icing signature on the Skew-T you should remember!

When departing out of an airport in any airplane, knowing the threat of icing is a key element to making good decisions.


Pilot weather reports or PIREPs are one of the best tools at diagnosing the potential for adverse weather including airframe ice. Here's a perfect example. As you can see here, this Mooney encountered moderate to severe rime ice at 14,000 feet MSL just southeast of the Great Salt Lake area. We'll discuss this later, but the fact that it was rime ice makes a lot of sense as well. But what if there wasn't such a PIREP? What's the best approach to diagnosing the potential for a dangerous icing situation? Well, first and foremost, it's understanding the big weather picture. But there's a lot going on in this area and the Skew-T log (p) diagram comes in handy as well if you know what to look for.


The Skew-T is an excellent drill down tool to explore the details that the big weather picture doesn't readily provide. For example, before departing (or upon arrival), it might not be a bad idea to check out the Skew-T for this area. The PIREP was offered at 21Z and here's the 1-hour forecast from the Rapid Refresh (RAP) model also valid at 21Z. Let's see if we can unpack all that is going on here...there's a lot.