Tropical Wave 07 Forecast To Move Across T&T Overnight, Bringing Showers & Thunderstorms

What you need to know:
— A tropical wave is moving across Trinidad and Tobago, with the axis of the wave forecast to move across the islands overnight tonight into Monday.
— Scattered showers and isolated thunderstorms are forecast to begin near midnight on Sunday and continue through the first half of Monday with mostly cloudy skies. A dry and breezy evening is forecast on Monday, with Saharan Dust returning across the region.
— There are no alerts, watches, or warnings in effect for T&T from the Trinidad and Tobago Meteorological Service at this time.

The Forecast

Sunday: Increasing cloudiness is forecast, with showers moving across Tobago initially and then Trinidad closer to midnight. Isolated to scattered showers and isolated thunderstorms are forecast to affect T&T with heavier rainfall favoring offshore eastern areas.

Monday: Showers and thunderstorms continue from midnight, gradually diminishing towards daybreak, with partly to mostly cloudy skies after sunrise. A few lingering showers are possible through midday, with breezy and hazy conditions returning for the second half of Monday. A mostly fair night is expected.

Marine: Seas are forecast to be slight over the next 12 hours, returning to moderate by the second half of Monday. Waves between 1.0 to 1.5 meters in Trinidad and Tobago’s open waters through Monday morning, becoming up to 2.0 meters by Monday night. Across sheltered coastlines, near calm seas are expected through Monday morning, with waves below 1.0 meters are likely by the evening. In heavy showers or thunderstorms, sheltered seas may become choppy.

Forecast Discussion

As of 6:00 PM, Tropical Wave 07 has been analyzed at 59/60W, south of 15N, moving westward at 15 to 20 knots (27 to 37 KM/H). The axis of the wave is just east of Trinidad and Tobago, but its large plume of moisture and instability is already moving across T&T.

This tropical wave is forecast to increase moisture at all levels of the atmosphere. Additionally, between 6:00 PM Sunday and 6:00 AM Monday, a supportive atmosphere is forecast with favorable low-level convergence and upper-level divergence for heavy shower and thunderstorm development, though wind shear will remain moderate to strong. With wind shear remaining from the southwest to west, the worst of the weather is forecast to remain offshore northern and eastern Trinidad and Tobago.

By Monday afternoon, the low to mid-levels of the atmosphere are forecast to dry due to a surge of Saharan Dust, limiting further significant rainfall until later next week, when Tropical Wave 08 moves across the region.

Total Precipitable Water Imagery showing the Tropical Waves (analyzed by the National Hurricane Center, Weather Prediction Center, and TTWC) that exist east of Trinidad and Tobago. (CIMSS, Space Science & Engineering Center, University of Wisconsin – Madison)


Across both islands, overnight lows are forecast to be mild, with daytime highs hot.

Over the next 24 hours, the minimum low for Trinidad and Tobago is forecast to be between 24.0°C and 26.0°C. The maximum high for Trinidad and Tobago is forecast to be between 30.0°C and 33.0°C.

Forecast Impacts

Forecast impacts due to Tropical Wave 07

Mainly overnight tonight into early Monday morning, the main hazards include heavy rainfall triggering localized street flooding and flash flooding. Lightning and gusty winds up to and in excess of 55 KM/H may accompany thunderstorms or heavy showers and cause power dips/outages, downed trees, and localized wind damage.

On Monday, the main hazards are gusty winds accompanying brisk showers and reduced air quality due to an increase in Saharan Dust.


Sustained surface winds up to 30 KM/H. In shower activity, gusts up to and in excess of 55 KM/H are possible. With wind gusts in excess of 55 KM/H, whole trees are expected to be in motion, and there may be some inconvenience when walking against the wind gusts. Light outdoor objects may topple or become airborne such as garbage cans, potted plants, loose galvanize or construction material and other outdoor furniture. Tents may jump. Older/weaker trees may fall, bringing down utility poles and lines.


Over the next 48 hours, overall higher rainfall is forecast to favor eastern Trinidad and Tobago, with accumulations between 20 to 30 millimeters as Tropical Wave 07 moves across the region. However, localized totals up to and in excess of 30 millimeters are possible in prolonged heavy showers or isolated thunderstorm activity. Note that highly isolated areas across western and northern areas of Trinidad may exceed daily forecast totals.

  • Sunday: Less than 5 millimeters of rainfall forecast across the country over the next several hours with isolated totals up to 15 millimeters favoring southern and eastern areas of Trinidad.
  • Monday: Most of the rainfall is forecast to subside during the morning. Still, less than 5 millimeters of rainfall is forecast across the country, with the eastern half of Trinidad recording up to 15 millimeters of rainfall. Higher totals may accumulate in localized areas.

As mentioned earlier, mainly Sunday night into early Monday morning, heavy rainfall may trigger localized street flooding and flash flooding.

Other Adverse Weather Impacts

Lightning: Lightning is possible in thunderstorm activity. Lightning can cause power outages, voltage dips, damage to life and property, particularly during cloud-to-ground lightning strikes.

Why I May Not/Will Not See Rainfall?

A frequent complaint is the forecast is wrong because I didn’t experience any rainfall. Scattered showers mean that you, individually, may experience some showers intermittently throughout the day and there is a higher chance for this activity than isolated activity. Widespread showers mean that nearly all persons and areas may experience rainfall.

On Sunday night into Monday morning, scattered rainfall is forecast.

Forecast - Isolated, Scattered, Widespread - What do they mean?

Facebook Comments