Rainfall and Temperature Outlook for Trinidad and Tobago, January to March 2020



ISSUED AT: 02:18 PM

Date: Wednesday 8th of January 2020

Key Messages
 
 
    • Both the 2019 wet season and annual rainfall totals were less than average across most areas of Trinidad and Tobago;
    • The month of January 2020 is likely to be slightly wetter than usual; however, the chances are highest for near normal rainfall totals over the three months January to March (JFM) 2020;
    • This means overall, typical dry season conditions are likely for JFM 2020;
    • Near-normal rainfall during the three months JFM is usually not a significantly large amount of rainfall. JFM rainfall on average accounts for only 8-14 % of the annual rainfall amounts;
    • Both day and night temperatures are predicted to be warmer than normal over Trinidad and Tobago during JFM 2020; however, one or two nights during the three months are likely to produce minimum temperatures below 22.0oC.
 

 

 

 

 

 
 

Likely Impacts

  • Existing rainfall deficiencies from the 2019 wet season have negative implications for water resource management. Expect reduced water recharge rates and slower than average stream flows;
  • Dry season conditions usually lead to an increase in the need to collect and store water in containers. This can increase breeding areas for mosquitoes if collected water is not stored adequately;
  • Dry season conditions will increase bush and forest fires potential, especially during late February and March;
  • Reduced air quality is likely during bush-, grass-, forest- and landfill-fires. This can negatively affect existing respiratory and other ailments.
 
 

 

 


Rainfall and Temperature Outlook for Trinidad and Tobago, January to March 2020



ISSUED AT: 02:18 PM

Date: Wednesday 8th of January 2020

 

January to March 2020 Likely To Be As Dry As Usual With Near Normal Rainfall Likely
 
 
 
 

Key Messages

  • Both the 2019 wet season and annual rainfall totals were less than average across most areas of Trinidad and Tobago;
  • The month of January 2020 is likely to be slightly wetter than usual; however, the chances are highest for near normal rainfall totals over the three months January to March (JFM) 2020;
  • This means overall, typical dry season conditions are likely for JFM 2020;
  • Near-normal rainfall during the three months JFM is usually not a significantly large amount of rainfall. JFM rainfall on average, accounts for only 8-14 % of the annual rainfall amounts;
  • Both day and night temperatures are predicted to be warmer than normal over Trinidad and Tobago during JFM 2020, however one or two nights during the three months are likely to produce minimum temperatures below 22.0oC.

 Likely Impacts

    • Existing rainfall deficiencies from the 2019 wet season have negative implications for water resource management. Expect reduced water recharge rates and slower than average stream flows;             
    • Dry season conditions usually lead to an increase in the need to collect and store water in containers. This can increase breeding areas for mosquitoes if collected water is not stored adequately;
    • Dry season conditions will increase bush and forest fire potential, especially during late February and March;
    • Reduced air quality is likely during bush-, grass-, forest- and landfill-fires. This can negatively affect existing respiratory and other ailments.

 
 

 

Early Actions & Preparedness

  • Continue water conservation programs and  awareness messages;
  • Revisit dry season contingency plans and upgrade based on historical extremes and not historical averages;
  • Conserve, store and manage water in a safe and adequate manner;
  • Take measures to lessen the impacts from dry season conditions. Be dry season ready. Stock up on water.
 

Figure 1: Category of rainfall likely for January to March (JFM) 2020 with the highest chance of occurrence expressed as probabilities and colour coded on the map. Blues indicate that it is more likely for above-normal rainfall to occur than for below-normal or near-normal. Browns indicate it is more likely for below-normal rainfall, while greens indicate it is more likely for near-normal rainfall. Normal is defined by the rainfall that was observed in middle one-third of the JFM 2020 period rainfall totals during the historical period used to produce the outlook.

  • January to March 2020 is likely to be as dry as usual with all areas of the country having higher chances for  near-normal rainfall for the three months;
  • The outlook indicates that rainfall totals for JFM are likely to be in the near-normal category  ( high confidence);
  • This means all areas are expected to receive rainfall totals between 75% and 125% of the average, during the period. Near-normal rainfall totals for JFM at Piarco range between 119.0 mm and 198.0 mm, while at Crown Point, they range between 122.0 mm and  203.0 mm;
  • While the outlook is for near-normal rainfall during JFM  2020,  a few months  of  above-average rainfall would be needed to see a recovery from last year’s  rainfall deficiencies.
 

Figure 2: The map shows the chances for extremely dry conditions over the next three months, Janaury to March (JFM) 2020. Extremely dry conditions refer to the lowest 10% of  January to March accumulated rainfall totals in the historical record.

  • The chance for JFM 2020 to be extremely dry is low across most areas (high confidence);
  • The outlook indicates a 50-60% chance for at least three 7-day dry spells during JFM 2020, i.e. seven consecutive days with no measurable rainfall.
 

Figure 3: Possible accumulated rainfall totals with the highest chance of occurring during  January to March 2020.

  • Areas in northeast Trinidad, near Sangre Grande, North Oropuche and environs are likely to receive the largest rainfall accumulated totals, while areas near Port of Spain in the northwest, and near Chatham in the southwest are likely to receive the least rainfall totals during the three months, JFM;
  • In Trinidad, accumulated rainfall totals are likely to range between 137.0 mm and 388.0 mm;
  • In Tobago, accumulated rainfall totals are likely to range between 173.0 mm near Crown Point in the southwest and 245.0 mm in the vicinity of Mount Saint George, in the northeast.
 

Figure 4: Possible rainfall totals with the highest chance of occurring during January 2020.

  • January is likely to be slightly wetter than average with a greater than 45% chance in most areas for rainfall totals in the above-normal category;
  • Possible rainfall totals range from 40.0 mm to 170.0 mm across both islands.
 

Figure 5:  Category of rainfall most likely for April to June 2020 (AMJ) with the highest chance of occurrence expressed as probabilities and colour coded on the map. Blues indicate that it is more likely for above normal rainfall to occur than for below normal or near normal. Browns indicate it is more likely for below normal rainfall; while greens indicate it is more likely for near normal rainfall. Normal is defined by the rainfall that was observed in middle one-third of the AMJ period rainfall totals during the historical period used to produce the outlook.

  • The rainfall outlook for April to June 2020 indicates higher chances for a wetter than normal conditions over these months.
 

The Temperature Outlook

  • From January through to March 2020 both day and night time temperatures are likely to be warmer than average for most of Trinidad and Tobago;
  • The chance for warmer than average maximum and minimum temperatures is greater than 60% over Trinidad and greater than 65% over Tobago;
  • Although warmer than average conditions are forecasted, uncomfortably high temperatures are not likely during the period, given that January and February are usually the coolest part of the year, locally;
  • On one or two cloud free nights, minimum temperatures are likely to cool below 22.0oC.

Likely Implications

  • Deficiencies in rainfall amounts during the recent 2019 wet season have negative implications for water resource management during JFM;
  • Expect reduced water recharge rates, slower and lower than usual stream flows and water levels;
  • Potential exists for an increase in the need to collect and store water in containers. This can increase breeding areas for mosquitoes;
  • Expect increased browning of weeds, grass, bush and some forest species as the season progresses;
  • Drying will increase bush and forest fires potential as the season progresses, especially during late February and March;
     
    Reduced air quality is likely during bush, grass, forest and landfill fires. This can negatively affect existing respiratory and other ailments;
  • Possibility of increased disruption in marine activities due to episodes of rough seas.
 

Early Actions & Preparedness

Water and Energy sector

  • Continue water conservation programs and  awareness messages;
  • Revisit dry season contingency plans and upgrade based on historical extremes and not historical averages.

General Public

  • Conserve, store and manage water in a safe and adequate manner. Take measures to lessen the impacts from dry season conditions. Be dry season ready. Stock up on water.

Disaster Risk Management Sector

  • Sensitize vulnerable communities on the forecast, its negative impacts and actions to be taken;
  • Review dry season contingency plans and early warning information dissemination channels.

Drainage

  • Continue de-silting and cleaning drainage systems, water channels, outlets and river mouths.

Waste Management Sector

  • Ramp-up contingency plans to mitigate the occurrence of landfill fires.

Health Sector

  • Revisit contingency plans to manage spikes in vector-borne and dust/smoke-related respiratory ailments, as well as, contingency plans to manage impact on hygiene and sanitation.

Agriculture & Food Security Sector

  • Raise awareness on agriculture pest and disease control measures and  bushfires risk;
  • Initiate contingency planning for expected drying as the dry season progresses.

Education Sector

  • Put in place contingency plans for maintaining adequate water supply within schools.

Be vigilant and visit the Met. Service website at www.metoffice.gov.tt regularly to keep up to date with local weather changes and follow us on social media.

 

Climatic Influencers and Context of the Outlook

  • Sea surface temperatures (SSTs) in waters surrounding Trinidad and Tobago are currently warmer than average. Multiple climate models suggest the ongoing warming is likely to continue with above-average temperatures likely during JFM 2020.
  • Warmer than average SSTs in waters east of Trinidad and Tobago are likely to be the primary driver of Trinidad and Tobago’s climate over the next 3 months.
  • SSTs in the equatorial Pacific Ocean are currently near to above average, but El Niño-Southern Oscillation-neutral (ENSO-neutral) conditions persisted during December 2019.
  • The consensus forecast suggests that ENSO-neutral conditions (neither El Niño nor La Niña) are likely to persist from January to May 2020.
  • Typically, ENSO-neutral conditions at this time of the year have very little control over Trinidad and Tobago’s climate. ENSO-neutral is not likely to be the major influence on the southeastern Caribbean climate pattern during JFM.
  • During December, the North Atlantic Oscillation (NAO) remained in its positive phase and is forecasted to persist in the positive phase during most of January 2020. A positive NAO tends to promote stronger trade winds, which can lead to the cooling of SSTs in waters surrounding Trinidad and Tobago.
  • The Madden Julian Oscillation (MJO) is known as the main climate feature which directly influence fluctuation in tropical weather on weekly to monthly timescales. The MJO is not likely to be of significant influence during January 2020.

The rainfall and temperature outlook is based on statistical and dynamical seasonal climate models output and known seasonal climate influencers. The outlook is in reasonable agreement with several of the global climate models. Multiple climate influencers appear to be at play and can cancel out each other.