Tropical Weather Update:
— Tropical Wave 10: The axis of this tropical wave is located several hundred kilometers east of Trinidad and Tobago, but is moving fairly quickly westward. The axis is forecast to move across Trinidad and Tobago during the first half of Sunday, with scattered to widespread showers, possible thunderstorms beginning after midnight tonight through Monday. Models have backed off heavy rainfall across T&T over the next 48 to 60 hours. Widespread inclement weather and significant rainfall are not expected.
— Tropical Wave 11: The axis of this tropical wave is well east of Trinidad and Tobago in the Central Atlantic. This is a fairly weak tropical wave, embedded within the ITCZ. It is forecast to move across T&T by late Friday into Saturday next week. As with weak tropical waves, no significant rainfall is forecast at this time. However, it is a week away so additional updates will be posted in a subsequent tropical update.
— No Tropical Development forecast elsewhere across the Atlantic basin over the next 5 days as of the latest tropical update.
Tropical Wave 10
The axis of Tropical Wave 10 is presently located along 55-58W, south of 15N, moving rapidly westward at 15-25 knots. Based on present model guidance, the axis of this wave is forecast to move across Trinidad and Tobago during the first half of Sunday, with increased cloudiness, showers and possible thunderstorms affecting Trinidad and Tobago beginning late tonight, lingering through Monday as previously indicated.
Over the next 48 hours, the large moisture field associated with this wave will move across Trinidad, Tobago and much of the Lesser Antilles. Wind shear is on the decline across T&T presently. Atmospheric conditions are likely to be slightly more favorable for heavy showers and thunderstorms following the passage of this wave. Hence, we’re looking towards Sunday for much of this forecast rainfall to occur.
This wave has significantly improved air quality across Trinidad and Tobago, returning air quality to good after days of air quality between moderate and unhealthy. However, another surge of Saharan dust is forecast to move across the Lesser Antilles following the passage of this wave, by June 25th, 2019.
Forecast For Trinidad and Tobago
Saturday Afternoon through midnight – Isolated showers are forecast interrupting sunny to partly cloudy skies, mainly across Trinidad. There is a low chance of a thunderstorm favoring Eastern Trinidad as well as Eastern Tobago.
Sunday, after midnight, through the mid-morning – Isolated to scattered showers, possible isolated thunderstorms across both islands. By dawn, scattered to possibly widespread showers are possible with isolated to scattered heavy showers and thunderstorms occurring. The heaviest activity is likely to occur east of Trinidad, south of Tobago through the mid-morning.
Sunday, late morning through the late afternoon – Scattered to widespread showers, isolated to scattered thunderstorms moving across mainly Trinidad. Isolated showers affecting Tobago. Generally cloudy conditions across the islands.
Sunday, late afternoon until midnight – Mostly settled at first with partly cloudy to cloudy skies across T&T. Isolated light to moderate showers possible, particularly after sunset, with moderate showers favoring Eastern Trinidad.
Monday – After a relatively settled morning with isolated showers, another round of scattered showers is possible by the late morning, possibly becoming widespread, with isolated thunderstorms favoring Trinidad through the late afternoon. Conditions are forecast to become settled by the evening, with another round of Saharan Dust likely to move across the islands on Tuesday.
Possible Impacts to Trinidad and Tobago
Locally Heavy Rainfall & Flooding: Based on the 12Z Saturday model runs:
– Saturday into Sunday (2:00 PM Saturday through 2:00 PM Sunday): Generally less than 10 millimeters across Trinidad and Tobago with lower totals likely across Western Trinidad, 10-30 millimeters of rainfall affecting parts of Central and Eastern Trinidad.
– Sunday into Monday (2:00 PM Sunday through 2:00 PM Monday): Generally less than 10 millimeters across Trinidad and Tobago with isolated areas receiving between 10-20 millimeters, favoring Eastern Trinidad and the Southern coast of Tobago.
The heaviest activity is forecast to occur on Sunday. Generally, with heavy showers and thunderstorm activity, street flooding, particularly in flood-prone areas or areas with poor drainage, is possible as well as flash flooding in areas where more prolonged heavy rainfall may occur, based on the above-mentioned forecast rainfall totals.
Frequent Lightning: In addition, with thunderstorms, frequent lightning is likely. Thunderstorms are forecast to occur mainly after midnight Saturday, mainly on Sunday, across T&T.
Gusty Winds: Gusty winds, generally between 50-60 KM/H are also possible. These wind gusts will generally occur prior to, in the vicinity of, or occur during heavy showers or thunderstorms. With wind gusts up to 60 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, loose galvanize or construction material and other outdoor furniture. Tents may jump.
Landslides: In landslide-prone areas, particularly in areas that receive heavy rainfall, landslides and/or mudflows may occur. These landslides, in addition to gusty winds, may down trees, utility poles and impede traffic on roadways.
This wave, based on present model guidance, is not forecast to produce widespread or scattered severe weather. However, isolated severe weather is possible as isolated to scattered heavy showers and isolated thunderstorms are in the forecast.
Tropical Wave 11
This tropical wave’s axis extends along 35W, south of 10N, moving west at 15-25 kt. Scattered showers and thunderstorms are noted near this feature from 05N-08N between 32W-37W.
This wave is forecast to move across T&T on Friday into Saturday of next week, bringing increased cloudiness, scattered showers and possible thunderstorms, favoring Southern Trinidad. The ITCZ may also pay another visit to the islands which may bring a heavy rainfall threat.
As of this tropical update, this wave is not forecast to produce widespread or scattered severe weather. However, isolated severe weather is possible as isolated to scattered heavy showers and isolated thunderstorms are in the forecast.
Tropical Cyclone Climatology
Tropical Cyclone Points of Origin during the month of June. Though attention is usually placed on the Western Caribbean, Gulf of Mexico and the Western Atlantic, a few storms have developed east of Trinidad and Tobago during the month of June, most recently and notably – Tropical Storm Bret in 2017.
In June, we turn our eyes to the Western Caribbean and the Gulf of Mexico for the formation of tropical cyclones in the Atlantic Basin, historically. However, tropical cyclones can form in the Atlantic Basin, without regard for the location once conditions support development.
There are NO tropical cyclone threats to the Eastern Caribbean, including Trinidad and Tobago at this time in the latest Tropical Update.