Rainfall and Temperature Outlook for Trinidad and Tobago, February to April 2019



ISSUED AT: 10:45 AM

Date: Thursday 31st of January 2019

Key Messages

  • The February to April 2019 climate outlook indicates drier than average conditions are likely across all of Trinidad and Tobago with below normal rainfall expected (high confidence);
  • The chance for drought, drought-like conditions or short duration dry spells during February to March is very much enhanced (high confidence);
  • There is a 60-80% probability for at least four 7-day dry spells during February to April;
  • Warmer than average days and nights are likely for the three months. There is high chance for an increase in hot days and hot spells from late February to April (high confidence);
  • The drier than usual February to April is due to cooler than average sea surface temperatures near Trinidad and Tobago and El Niño-like atmospheric features.

 

 

 

Likely Impacts

  • Reduction in ground water recharge, surface water flows and faster depletion of large reservoirs;
  • Drier and hotter conditions will increase bush, forest and landfill fire potential;
  • Reduced air quality possible during bush, forest and landfill fires;
  • Drier than average conditions enhance the chance for some agricultural pests and diseases to thrive;
  • Periods of excessive heat can increase heat-stress for persons with heat-sensitive ailments, crops and for heat-exposed livestock, pets and other animals.


Rainfall and Temperature Outlook for Trinidad and Tobago, February to April 2019



ISSUED AT: 10:45 AM

Date: Thursday 31st of January 2019

Drier Than Normal Three Months (February to April) Likely For Trinidad and Tobago

Key Messages

  • The February to April 2019 climate outlook indicates drier than average conditions are likely across all of Trinidad and Tobago with below normal rainfall expected (high confidence);
  • The chance for drought, drought-like conditions or short duration dry spells during February to March is very much enhanced (high confidence);
  • There is a 60-80% probability for at least four 7-day dry spells during February to April;
  • Warmer than average days and nights are likely for the three months. There is high chance for an increase in hot days and hot spells from late February to April (high confidence);
  • The drier than usual February to April is due to cooler than average sea surface temperatures near Trinidad and Tobago and El Niño-like atmospheric features.

Likely Impacts

  • Reduction in ground water recharge, surface water flows and faster depletion of large reservoirs;
  • Drier and hotter conditions will increase bush, forest and landfill fire potential;
  • Reduced air quality possible during bush, forest and landfill fires;
  • Drier than average conditions enhance the chance for some agricultural pests and diseases to thrive;
  • Periods of excessive heat can increase heat-stress for persons with heat-sensitive ailments, crops and for heat-exposed livestock, pets and other animals.

 

Figure 1: Category of rainfall likely for February to April 2019 (FMA) 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 FMA period rainfall totals during the historical period used to produce the outlook.

  • The February to April 2019 rainfall outlook shows that there are very strong indications for drier than usual conditions across the country, with the below normal rainfall category as the most likely (high confidence) ;
  • Below normal rainfall totals mean areas are likely to receive rainfall totals that are less than 75% of the long term average for FMA. For instance, at Piarco, below normal rainfall for FMA is rainfall that is less than 139.8 mm and at Crown Point, rainfall less than 129.8 mm.
     

Figure 2: The map shows the chances for extremely dry conditions over the three months ending April 2019. Extreme refers to the lowest 10% of February to April accumulated rainfall in the historical record.

  • The chance for the FMA period to be extremely dry is moderate (high confidence);
  • The outlook indicates a 60-80% chance for at least four 7-day dry spells during FMA, i.e. seven consecutive days with no measurable rainfall;
  • The chance for drought, drought-like conditions or short duration dry spells during February to April has increased (high confidence).
     

Figure 3: Possible accumulated rainfall totals with the highest chance of occurring during February to April 2019.

  • Most of Trinidad and Tobago is likely to receive less than 200mm during the three months. A few areas in north east Trinidad are likely to receive just above 200mm of rainfall.
  • The lowest totals are likely in Tobago and southwest Trinidad.

Figure 4: Possible rainfall totals with the highest chance of occurring during February 2019.

  • Drier than usual rainfall totals are likely for February with greater than 50% chance for rainfall in the below normal category (high confidence);
  • Possible rainfall totals range between 20.0mm and 65.0mm across the twin island Republic.

Figure 5:  Category of rainfall most likely for May to July 2019 (MJJ) 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 MJJ period rainfall totals during the historical period used to produce the outlook.

The early outlook for May to July 2019 indicates drier than average conditions for most of Trinidad and Tobbago with a few areas likely to receive near normal rainfall (moderate confidence).

 

Temperature Outlook:

  • February to April daytime temperatures are likely to be warmer than average for all of Trinidad and Tobago;

  • The chance for warmer than usual maximum temperatures is greater than 80 % over Trinidad and greater than 70% over Tobago;
  • Nights are also very likely to be warmer than average. The chance for warmer than average nights exceeds 70%;

  • Few nights in early February are likely to have minimum temperatures cooled below 22.0oC on cloud free nights.

Likely Implications:

  • Expect a continuation of reduction in ground water recharge, surface water flow and water availability;
  • Drier than average conditions can increase the need to collect and store water in containers which can increase breeding areas for mosquitoes;
  • Drier than average conditions can lead to late development of some agricultural crops and change in the harvest time;
  • Drier than average conditions and warmer than average temperatures tend to favour better quality in some fruits;
  • Drier than averagec onditions may favour some outdoor activities such as those in the tourism industry;
  • Drier and hotter conditions will increase the chance for bush, landfill and forest fires;
  • Bush, landfill and forest fires are likely to reduce air quality;
  • Periods of excessive heat can increase heat-stress for persons with heat-sensitive ailments, heat-exposed livestock and other animals.
     

    Sectorial Early Action That Can Be Taken  To Reduce Possible Disaster Effects!                

    Water and Energy sector

  • Escalate water conservation awareness messages;
  • Conduct routine de-silting of reservoirs and riverine channels;

         Disaster Risk Management Sector

  • Sensitize communities and citizens on the forecast, its negative impacts and early actions to be taken;
  • Consider who may be most affected by the deficit rainfall forecast;
  • Review your contingency plans and update as necessary;
  • Revisit early warning information dissemination channels.

        Drainage

  • Use drier conditions to de-silt, clean and upgrade drainage systems, water channels and river mouths;

      Waste Management Sector

  • Ramp-up contingency plans to mitigate landfill fire occurrence;

       Health Sector

  • Clear bushes, open drainage systems, fumigate in and around residences;
  • Revisit contingency plans to manage spikes in respiratory, heat-related and vector-borne ailments.

       Agriculture & Food Security Sector

  • Put in place pest and disease control measures; raise awareness on the increased risk of bushfires;
  • Initiate contingency planning for drier than usual conditions.

       General Public

  • Continue preparation especially for persons at risk. Stock up on water and emergency supplies for 3-7 days;
  • Conserve, store and manage water in a safe and adequate manner;
  • Take measures to lessen impacts from drier than usual conditions. Be dry season ready;

       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

  • Waters in, and around Trinidad and Tobago are currently near to below average and are forecasted to be near average during the FMA;
  • The warming trend of sea surface temperatures (SSTs) in the central and eastern equatorial Pacific Ocean decreased during December and early January but maintained El Niño threshold levels even though the El Niño–Southern Oscillation (ENSO) remains in neutral phase.
  • Current observations and model outlooks show reduced chance (70%) for El Niño to develop during FMA;
  • The North Atlantic Oscillation (NAO) fluctuated from negative to positive phase during January and is likely to persist in positive phase during February. A positive NAO tends to aid in cooling SSTs in waters around Trinidad and Tobago.