Tropical Discussion - International Desks NWS Weather Prediction Center College Park MD 218 PM EST Fri Feb 14 2025 Forecast Bulletin 14 February 2025 AT 1900 UTC Note: Tropical Desk products will be paused on Monday 17 February 2025 due to the federal holiday and will resume on Tuesday 18 February 2025. We apologize for the inconvenience. The overall rainfall pattern has not changed much over the Caribbean basin into Central America and Mexico over the past few days, and not much change is expected through the weekend. Brief showers in the windward portions of the Caribbean islands and in some areas of Central America can be expected this weekend as well. Tropical South America, where most of the rainfall has been observed over the past few days, can expected areas of significant rainfall this weekend as well, but the west coast of Ecuador and Colombia will see a decrease in shower activity and amounts of rain this weekend. The moisture field over the area will have areas of near to below normal moisture across the Caribbean, with a few patches of higher moisture. Near to slightly above normal available moisture is expected across Central America and Mexico. That said, most of the moisture is expected to be limited to the lower levels, as the 500mb level is fairly dry through the Caribbean basin into Mexico. Tropical South America does have near to above normal moisture through the region, and will continue through the weekend. The mid levels over northern South America also have good moisture. However, there are westerly equatorial winds over the eastern Pacific that will move into western Ecuador and Colombia, bringing drier air aloft. Because the moisture column over this area will not be as deep, the daily rainfall forecast for the area is lower than what was observed over the past several days. That said, the moisture over northern South America in and around the Amazonas to the Guianas and other portions of northern Brasil remain adequate to fuel decent diurnal shower and thunderstorm development over the area. The mid to upper levels across the Caribbean into Central America will still be dominated by a ridge of high pressure, with the exception of a retrograding trough in the mid levels over Hispaniola. Therefore, for the most part, a relatively stable mid to upper levels are expected across the area. Thee are a few shortwave troughs in the lower levels, however. These troughs will cause low-level moisture convergence and some local enhancement of shower activity, though mostly it will be over the waters. The areas with slightly enhanced shower activity over the Caribbean into Central America will move quickly west as there is a large area with low-level winds of over 25KT. Because the winds are fairly strong in the lower levels, the shower activity will be brief over any one area, causing the overall rainfall accumulations to be modest across the Caribbean into Central America, in most cases maxing out at around 15-20mm each day across isolated areas and even lower accumulations in most areas. The Lesser and Greater Antilles are forecast daily maxima of up to 10-15mm each day across isolated areas, while most areas will observe minimal accumulations. Mexico will be failry dry through the weekend, with little to no rainfall accumulations in the forecast today and Saturday. However, a cold front is forecast to push south by Sunday night, causing some moisture to pool over Veracruz and Oaxaca. There will also be a trong low-level jet known as the Tehuantepecer, which will provide persistent moisture convergence with land interactions over the area. Therefore, up o 35mm of rain is forecast for portions of Veracruz, Oaxaca, and into Chiapas on Sunday into Monday morning. Across northern South America, the diffluent pattern aloft and the normal to slightly above normal moisture will combine each day to cause areas of showers and thunderstorms. The highest accumulations are expected across Amazonas today and Satuday, with daily totals that could be as much as 40-80mm, but for Sunday the highest amounts of rain are forecast to be over the Guianas into Para and Amapa of Brasil, with maxima of 30-60mm. Western Ecuador and Colombia are forecast showers and thunderstorms each day into the weekend, but the daily rainfall maxima are forecast to be near 20-45mm as the aforementiones drier air aloft may play a role in how deep the convection actually develops. Therefore a more scattered and not quite as widespread or efficient thunderstorm development is forecast, compared to what was observed earlier in the week. Alamo...(WPC)