Date: Monday 18th of February 2019

Weak El NiƱo Declared : Forecasted To Persist Over The Remainder Of The 2019 Dry Season


The warming trend of sea surface temperatures (SSTs) in the central and eastern equatorial Pacific Ocean continued during January and early February with corresponding changes in the overlying atmospheric circulation. This has led to the equatorial Pacific Ocean transitioning from El Niño–Southern Oscillation (ENSO) neutral state to weak El Niño conditions. As such, a weak El Niño has been declared. The latest forecasts by the majority of international climate models indicate that the current El Niño is likely to persist for the rest of the 2019 local dry season. Accordingly, the Meteorological Services Division’s ENSO monitor switches to El Niño ongoing.

What does this mean for Trinidad and Tobago?

El Niño during the dry season typically means suppression of rainfall in Trinidad and Tobago, leading to rainfall deficits. At the same time, daytime temperatures tend to be warmer than average, especially during the mid to late-dry season. Potentially, these conditions typically favour a shift in temperature extremes and increased incidence of bush fires.

Guide:  An El Niño is declared when the average SSTs in the central and eastern equatorial Pacific Ocean become at least 0.5oC warmer than average in the preceding month and the warming is expected to persist for five consecutive overlapping three-month periods. This must occur together with a corresponding change in overlying the atmospheric circulation, manifested by: reduced rainfall and thunderstorm activity over Indonesia and increased rainfall activity over the central or eastern Pacific Ocean; weakened easterly low-level winds or westerly wind anomalies in the low levels across the equatorial western Pacific Ocean; and westerly upper-level wind anomalies in the eastern Pacific Ocean.  The TTMS El Niño/La Niña Watch is activated when the ENSO Outlook indicates a probability of approximately 50% chance or greater for development of El Niño or La Niña.