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Use the closest airport with a TAF, is that a good idea?

Let's say you are planning a flight and your destination airport does not have a terminal aerodrome forecast (TAF) issued for that airport. Can you simply use the closest airport that has a TAF? It is not unusual for a pilot during their preflight planning to simply use that closest airport. What's disturbing is that if you look at the most popular aviation apps, they actually encourage this by listing the closest airport that has a TAF. This can be very dangerous and lead to a poor decision.

It's important to acknowledge that the size of the terminal area is incredibly small. The definition is defined by the National Weather Service (NWS) as...

"...the area within five (5) statute miles (SM) of the center of an airport’s runway complex."

When a meteorologist is constructing this forecast, they are sensitive to this definition. In other words, a TAF is a point forecast and not a zone or area forecast. Therefore, forecasts for adverse weather such as thunderstorms, freezing rain and even windspeed or gusts, for example, are often issued with that tiny forecast area in mind. The expected weather just 10 miles away (outside of the terminal area) may be entirely different. This may be due to terrain such as mountains or even a body of water. Airports just 10 miles further inland may not experience the marine layer that may occur at airports right along the coast.

Here's a perfect example. As shown above, the Essex County (KCDW) and Teterboro (KTEB) airports are just 10 miles apart. However, the wind at these two airports may be completely different. Teterboro has a TAF, but Essex County does not. In fact, the TAF for Teterboro on October 27, 2021 forecast the winds in the early morning hours to be somewhat gusty as shown below.