Summary of Expected conditions:

Although near-to or below-normal rainfall amounts are forecast across various farmlands September 16^th to 30^th, heavy showers are likely to cause street/flash flooding on low-lying fields and access roads during the wet days expected on  17^th - 18^th ; 22^nd - 25^th ; and 28^th - 30^th . The moist soil conditions combined with lighter winds and occasionally hot conditions will maintain a moderate to high risk of pests/disease and a moderate risk of heat hazards.

Weather Assessment for the period 1^st to 15^th September 2025.

During the first 15-day period, below-normal rainfall occurred across various farmlands.  At Piarco, one wet day (2^nd) and nine relatively wet days resulted in a 15-day rainfall total of 52.6 mm. At Crown Point, two wet days (14^th and 15^th ) and four relatively wet days contributed to a 15-day rainfall total of 46.0 mm at Crown Point. The rainfall totals maps for the period 1^st to 15^th of September for Trinidad and Tobago are located below as figure 1 and figure 2.

Figure 1. Rainfall map of Trinidad showing measured rainfall totals for varying districts during the period 1^st to 15^th of September 2025.

Figure 2. Rainfall map of Tobago showing measured rainfall totals for varying districts during the period 1^st to 15^th of September 2025.
 

Temperatures:

For the second half of September, nights have been consistently warmer than normal, while daytime temperatures remained near normal. Piarco observed one hot day (maximum temperature over 34.0 ⁰C) with a maximum daytime temperature 34.0 ⁰C (10^th) however, the night-time minimum temperatures ranged from 23.4 ⁰C to 25.1 ⁰C at Piarco. Tobago did not observe any hot days (maximum temperatures above 33.0 ⁰C at Crown Point) however warm nights continued. The maximum daytime temperature was 32.5 ⁰C (10^th) and the minimum temperatures ranged from 24.5 ⁰C to 26.5 ⁰C at Crown Point. Factoring the relative humidity however these temperatures had a ‘real feel’ that was higher than the observed maximum temperature.

Agro-meteorological Forecast: 

Date	Weather			Temperature	Heat ‘Real Feel’	Day Moisture (Relative Humidity)	Wind
16	40% chance of rainfall	1-5 mm of rainfall is possible	Partly/mostly cloudy, isolated heavy shower /thunderstorm	Very Warm Max/Min Temperatures 33°C/24°C	Feels like 38°C-39°C	59-74%	East 20-39 km/h Gust 50 km/h
17	70% chance of rainfall	1-8 mm of rainfall is possible	Partly/mostly cloudy, isolated heavy shower /thunderstorm	Very Warm Max/Min Temperatures 33°C/24°C	Feels like 37°C-39°C	58-74%	East 20-30 km/h Gust 50 km/h
18	70% chance of rainfall	1-10 mm of rainfall is possible	Partly/mostly cloudy, isolated heavy shower /thunderstorm	Hot Max/Min Temperatures 34°C/24°C	Feels like 39°C-45°C	67-77%	East 20-30 km/h Gust 50 km/h
19	60% chance of rainfall	1-8 mm of rainfall is possible	Partly/mostly cloudy, isolated heavy shower /thunderstorm	Hot Max/Min Temperatures 34°C/24°C	Feels like 39°C-45°C	67-77%	Southeast-south 11-30 km/h Gust 50 km/h
20	60% chance of rainfall	1-6 mm of rainfall is possible	Partly/mostly cloudy, isolated heavy shower /thunderstorm	Hot Max/Min Temperatures 34°C/24°C	Feels like 39°C-45°C	67-77%	Southeast-south 11-30 km/h Gust 50 km/h
21	40% chance of rainfall	1-8 mm of rainfall is possible	Partly/mostly cloudy, isolated heavy shower /thunderstorm	Very Warm Max/Min Temperatures 33°C/24°C	Feels like 38°C-40°C	60-77%	East-southeast 11-30 km/h Gust 50 km/h
22	60% chance of rainfall	3-10 mm of rainfall is possible	Partly/mostly cloudy, isolated heavy shower /thunderstorm	Very Warm Max/Min Temperatures 33°C/24°C	Feels like 38°C-40°C	60-74%	East-southeast 11-30 km/h Gust 50 km/h
23	60% chance of rainfall	3-10 mm of rainfall is possible	Partly/mostly cloudy, isolated heavy shower /thunderstorm	Very Warm Max/Min Temperatures 33°C/24°C	Feels like 38°C-40°C	60-75%	East-southeast 11-30 km/h Gust 50 km/h
24	60% chance of rainfall	3-10 mm of rainfall is possible	Partly/mostly cloudy, isolated heavy shower /thunderstorm	Very Warm Max/Min Temperatures 33°C/24°C	Feels like 38°C-40°C	60-75%	East-southeast 11-30 km/h Gust 50 km/h
25	60% chance of rainfall	3-10 mm of rainfall is possible	Partly/mostly cloudy, isolated heavy shower /thunderstorm	Very Warm Max/Min Temperatures 33°C/24°C	Feels like 39°C-40°C	60-75%	East-southeast 11-30 km/h Gust 50 km/h
26	60% chance of rainfall	3-8 mm of rainfall is possible	Partly/mostly cloudy, isolated heavy shower /thunderstorm	Hot Max/Min Temperatures 34°C/24°C	Feels like 41°C-42°C	60-75%	East-southeast 11-30 km/h Gust 50 km/h
27	60% chance of rainfall	3-8 mm of rainfall is possible	Partly/mostly cloudy, isolated heavy shower /thunderstorm	Hot Max/Min Temperatures 34°C/24°C	Feels like 41°C-42°C	60-75%	East-southeast 11-30 km/h Gust 50 km/h
28	60% chance of rainfall	3-10 mm of rainfall is possible	Partly/mostly cloudy, isolated heavy shower /thunderstorm	Very Warm Max/Min Temperatures 33°C/24°C	Feels like 39°C-40°C	60-75%	East-southeast 20-30 km/h Gust 50 km/h
29	60% chance of rainfall	5-10 mm of rainfall is possible	Partly/mostly cloudy, isolated heavy shower /thunderstorm	Very Warm Max/Min Temperatures 33°C/24°C	Feels like 39°C-40°C	60-75%	East-southeast 20-30 km/h Gust 50 km/h
30	60% chance of rainfall	5-10 mm of rainfall is possible	Partly/mostly cloudy, isolated heavy shower /thunderstorm	Very Warm Max/Min Temperatures 33°C/24°C	Feels like 39°C-40°C	60-75%	East-southeast 20-30 km/h Gust 50 km/h

Trinidad Rainfall Forecast for the 15-Day period of September (16^th to 30^th) 2025.

 Figure 3.  Rainfall map of Trinidad showing expected mean rainfall totals for districts across Trinidad during the 15-day period (16^th to 30^th) September 2025 and percentage probability of occurrence.

Eastern and North-Eastern areas: Moderate chance (60%) of mean daily rainfall up to 4.9 mm.

South-Eastern areas: Moderate chance (60%) of mean daily rainfall up to 4.2 mm.

Southern areas: Moderate chance (65%) of mean daily rainfall up to 4.3 mm.

South-Western areas: Moderate chance (65%) of mean daily rainfall up to 4.3 mm.

Central, West-Central, and inland areas: Moderate chance (60%) of mean daily rainfall up to 4.2 mm.

Northern, North-Western areas: Moderate chance (65%) of mean daily rainfall up to 4.6 mm. 

Tobago Rainfall Forecast for the 15-Day period of September (16^th to 30^th) 2025.

Figure 4.    Rainfall map of Tobago showing expected mean rainfall totals for districts across Tobago during the 15-day period (16^th to 30^th) September 2025 and percentage probability of occurrence.

North-Eastern areas: Moderate chance (65%) of mean daily rainfall up to 5.0 mm.

South-Western areas: Moderate chance (55%) of mean daily rainfall up to 3.5 mm.

Trinidad and Tobago:

During the 15-days, there is a moderate (60%) chance for near-to or below-normal rainfall. The 15-day period forecast rainfall totals in Trinidad are expected to range between 44 mm and 102 mm favoring northern hilly areas of Trinidad, see figure 3. In Tobago, 15-day forecast rainfall is expected to range between 44 mm and 85 mm favouring farmlands along windward hillsides, see figure 4. There will be a moderate (60%) chance of mildly wet conditions across most farmlands during the period. 

Temperatures & Winds:

There will be a moderate potential of heat stress during the 15-days: a high (70%) chance of warmer than average nighttime temperatures combined with a moderate (60%) chance of above normal daytime temperatures. There is a moderate (65%) chance of two hot days in a row. Temperatures are expected to feel as hot as 37°C to 45°C when factoring humidity on the hottest days when daily maximum temperatures of 32-34 °C are forecast. Warm nights with minimum temperatures of 24-27°C are expected (especially for southwestern Tobago and western Trinidad).

Generally, light to moderate southeasterly winds (near average wind speeds) are expected however there is a moderate to high (70%) chance of occasional gusts of 50 km/h or higher near heavy showers or isolated thunderstorms. Evaporation rates up to 5.0 mm per day on average are expected especially on hot days forecast during the period. 

Moisture levels:

Moderate to high moisture levels are expected across Trinidad and Tobago over the fifteen-day period, with average daytime relative humidity values expected from the high-50s to high-70s, in terms of percentage.

Highlighted Possible Impacts on Agriculture:

During the 15-days, a heightened risk of heat hazards during September remains for farm workers, young livestock, newly germinated and transplanted seedlings onto fields. Mildly wet and very warm/hot conditions combined with gentle winds will maintain a moderate to high risk of pests/disease and a moderate risk of heat hazards nationwide. There is a moderate to high (70%) chance for fungal spread, insect pests and warm/moist weather diseases to develop in crop beds. 

Heavy showers occurring on saturated soils will bring a moderate to high risk of street/flash flooding, overfilling ponds, land slippage on fields and access roads. 

Strong gusts will likely damage young plants and flowering mature plants in exposed hilly areas. 

So, continue to monitor streams and nearby watercourse levels. Implement pest and disease control measures as recommended. Monitor crops and animals for signs of heat stress and irrigate crops as needed especially in the flowering stage.

Sun and Moon Positions in the Sky September (16^th to 30^th) 2025.

The sun is presently at latitude 2.3 degrees North of the Equator. The day-length or number of sunlight hours in Trinidad and Tobago from September 16^th will be 12 hours, 10 minutes decreasing to 12 hours, 1 minute on September 30^th.

Moon Phases: New Moon, 21^st and First Quarter,29^th. According to the tradition of moon phases: September 16^th is a good day for planting below-ground crops; 21^st – 25^th and 29^th – 30^th are good days for planting above-ground crops; the remaining days are poor planting days and useful for removing weeds, clearing land and ploughing fields.