Caribbean Low Level Jet Index

The Caribbean Low Level Jet (CLLJ) index presented here has been used by some authors to understand and forecast rainfall variability in regions of Central America, northern South America and the Caribbean.

Positive values indicate stronger CLLJ activity, and viceversa. In some locations, a stronger CLLJ could be associated with more (or less) rain, while some authors have suggested a relationship with the length of the mid-summer drought in places exhibiting this climate feature.

The CLLJ index is provided in this maproom as a monitoring tool of the magnitude of the winds anomalies in the region defined by 12.5˚N-17.5˚N, 80˚W-70˚W (as defined by Wang, 2007). No forecast of this index is provided here at the moment.


Wang, C. (2007) ‘Variability of the Caribbean Low-Level Jet and its relations to climate’, Climate Dynamics, 29(4), pp. 411–422. doi: 10.1007/s00382-007-0243-z. Krishnamurthy, L. et al. (2018) ‘Assessment of summer rainfall forecast skill in the Intra-Americas in GFDL high and low-resolution models’, Climate Dynamics, 17 May, pp. 1–18. doi: 10.1007/s00382-018-4234-z.

Dataset Documentation

MONTHLY Intrinsic PressureLevel u zonal wind from NOAA NCEP-NCAR CDAS-1: Climate Data Assimilation System I; NCEP-NCAR Reanalysis Project.

Data Source: CLLJI.

How to use this interactive graph


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