Dry season has officially started

THE Met Office has officially declared the start of the 2025 dry season.

In a release on January 14, it said the dry season started on January 14 and may run until May.

"At this time, the atmosphere over the region has transitioned to its drier state following a gradual transition from the wet into the dry season," the release said.

The dry season, it said, occurs once the following "synoptic features" are observed:

• The intensification and equatorward migration of the North Atlantic sub-tropical high-pressure cell;
• Strengthened trade-wind inversion (west Africa, central tropical Atlantic and eastern Caribbean);
• Upper-level westerly winds and
• Inter-Tropical Convergence Zone (ITCZ) in its southernmost position across the tropical Atlantic Ocean.

The Met Office said, "During early January, the climatic patterns and features (a relatively weak North Atlantic Sub-Tropical Pressure cell and strong upper-level easterly winds) had delayed the full formation of the dry season.

"There has been an observed reduction in the frequency of showery and/or rainy weather over Trinidad and Tobago during the last few weeks resulting from dry season synoptic features, such as passing mid-latitude frontal systems inducing moist low-level perturbations over the region."

During the dry season, people can expect reduced moisture, increased atmospheric stability, fewer deep clouds, less frequent rainfall events, warm days and cool nights, and a general shift in the surface wind direction to mostly easterlies to north easterlies.

The Met Office said relevant agencies and ministries should take measures to mitigate the potential impacts of the dry season.

The public, it said, should conserve, store and manage water in a sustainable manner.

People should refrain from burning rubbish in grassy or forested areas during the dry season.

However, the Met Office said, that although the dry season experiences significantly reduced rainfall amounts as compared to the wet season, it is not devoid of rainfall.

These rainfall events are not expected to be a result of wet-season systems such as the ITCZ, tropical waves, or tropical cyclone activity but from dry season synoptic features such as the passage of induced moist low-level perturbations from mid-latitude frontal systems and convergence bands of clouds over the region.

There is likely to be some rainfall from January-March.

"The recently declared weak La Niña in the central tropical Pacific Ocean is expected to positively influence rain-producing synoptic features in the dry season and therefore enhance rainfall totals mostly in the early season months of January-March and less so in April and May," the release said.

Initial wetter-than-usual and warmer-than-usual conditions during January, February and March may result in:

• Less vegetative stress due to relatively less surface dryness;
• A positive impact on surface and groundwater recharge and stream flow rates;
• An increase in the breeding areas for insect vectors such as mosquitoes due to uncovered water storage devices and water pooling in drains, low-lying areas and roof guttering;
• A decrease in the potential for bush, forest and landfill fires, especially during January-March.