What Is An Invest?

As hurricane season rolls around, you may start to hear the term “invest” used, but what does it mean?

An 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.

However, just because an invest is identified does not necessarily mean the system will become a tropical depression or storm.

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These invests will usually be festering clusters of showers and thunderstorms that do not yet have a persistent low-level circulation, but might show signs of organization.

How the naming system works for invests

• The term “invest” is followed by a number 90 through 99 and then a letter, such as Invest 90L.
• The first invest of the season starts with 90, the next with 91, etc. until it reaches 99, then loops back around to 90.
• The letter signifies the basin that the invest is in, with the letter “L” for the Northern Atlantic basin systems or “E” for the Eastern Pacific basin systems.
• The numbering system is separate for each basin, so there can be an Invest 90L and Invest 90E simultaneously.

What invests signify

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.

That 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.

Miriam Guthrie graduated from the Georgia Institute of Technology with an undergraduate degree in Atmospheric and Oceanic Sciences and is now a meteorology intern with weather.com before returning to school for her masters.