Invest (meteorology)


An invest in meteorology is a designated area of disturbed weather that is being monitored for potential tropical cyclone development. Invests are designated by three separate United States forecast centers: the National Hurricane Center, the Central Pacific Hurricane Center, and the Joint Typhoon Warning Center.

Overview

Invests are designated by three separate forecast centers located in the United States: the National Hurricane Center in Miami, Florida, overseeing the North Atlantic and North Eastern Pacific basins ; the Central Pacific Hurricane Center in Honolulu, Hawaii, monitoring the North Central Pacific basin ; and the Joint Typhoon Warning Center in Pearl Harbor, Hawaii, serving U.S. government interests elsewhere. The designation of a system as an invest does not necessarily correspond to any particular likelihood of development of the system into a tropical cyclone.

Designation

Invests are numbered from 90 to 99, followed by a suffix letter "L" in the North Atlantic basin, "E" and "C" in the Eastern and Central Pacific basins, or "W" in the Western Pacific basin.
The Joint Typhoon Warning Center also issues unofficial warnings for U.S. government interests in the Southern Hemisphere, designating tropical invests with the "S" suffix when they form west of 135°E, and the "P" suffix when they form east of 135°E. In addition, invests in the North Indian Ocean cyclone basin are also labelled by the JTWC, and are suffixed with "A" if they form in the Arabian Sea and with "B" if they form in the Bay of Bengal.
The Naval Research Laboratory's Marine Meteorology Division also uses the "Q" suffix to designate invests which form in the South Atlantic Ocean, even though it is not recognized as an official tropical cyclone basin by the World Meteorological Organization.
These suffix letters are also used with the tropical cyclone numbers assigned to tropical and subtropical depressions monitored by the NHC & CPHC and all tropical, subtropical, and potential tropical cyclones tracked by the JTWC.

Rotation

Numbers are rotated within the season and are re-used as necessary. In contrast, TC numbers assigned to proper cyclones are not recycled until the following year/season. If the invest system develops into a tropical cyclone, it is reclassified as the next name/number on the list.The NHC also numbers cyclones based on previous seasons.