What Is An Invest, Anyway?

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Y​ou may hear the term "invest" used during hurricane season. While it doesn't mean a system has become a tropical depression or storm, it does have significant meaning among meteorologists.

A​n invest – short for "investigation" – is a naming convention used by the National Hurricane Center (NHC) to identify features they are monitoring for potential future development into a tropical depression or storm.

T​hese invests will usually be festering clusters of showers and thunderstorms that do not yet have a persistent low-level circulation.

Here's what the nomenclature means: T​he term "invest" is followed by the numbers 90 through 99 and either the letter "L" for the Atlantic Basin systems or "E" for the Eastern Pacific systems. These full labels in the Atlantic would be Invest 90L, Invest 91L, etc.

Once the end of the list is reached with either Invest 99L in the Atlantic or Invest 99E in the Eastern Pacific, it starts back over again with Invest 90L or Invest 90E.

H​ere's what that signifies: According to the NHC, by designating a tropical weather system as an invest, the collection of specialized data sets and computer models on the area of interest can begin.

T​hat includes the scheduling of Hurricane Hunter aircraft missions and the running of hurricane models, including the well-known spaghetti model tracks.

However, just because a system has been called an invest doesn't guarantee development into a tropical depression or storm.

Invests do not count in the season's statistics like storms and hurricanes.

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