Tropical Discussion - International Desks NWS Weather Prediction Center College Park MD 1020 AM EST Thu Feb 20 2025 FORECAST BULLETIN 20 FEBRUARY 2025 AT 15:00 UTC ...Large Scale Conditions... MJO: The MJO is currently in phase 8. This MJO phase generally favors upper level divergence in the Americas. Kelvin Wave: none significant kelvin wave approaching the Caribbean basin. ENSO conditions: La NiÃa The weather pattern has remained generally stable... with typical la niÃa conditions prevailing throughout the entire basin this February. ...Synoptic conditions in the Caribbean basin... A surface front is currently advancing southward into the Caribbean region. By Thursday evening, this front is expected to extend across the northwest Bahamas, northwest Cuba, the northern Yucatan Peninsula, and into the Tehuantepec Pass. In the western areas, a stationary boundary is projected to establish itself across the Sierra Madre Oriental and southwest Coahuila. As we move into Friday evening, the cold front will be positioned over the southeast Bahamas, while the stationary boundary will continue to stretch through central Cuba and into the northwest Yucatan Peninsula. On Saturday the cold front will be located east of Cuba. ...Precipitation in the Caribbean... Isolated maxima of 10 to 15mm in some Caribbean islands. The island with the largest impact will be Cuba. ...Synoptic conditions in Mexico... As the previously mentioned cold front progresses, it will interact with the developing Tehuantepec low-level jet (LLJ), which is forecasted to form on Thursday with wind speeds expected to exceed 40 knots. This interaction is likely to lead to significant weather changes, particularly regarding precipitation. The heaviest rainfall is anticipated to concentrate in the eastern areas, where there is an elevated risk of thunderstorms due to enhanced upper divergence, high moisture levels, and instability. Beginning early Thursday, the most substantial precipitation is expected in Tabasco, Chiapas, and southern Veracruz. In these regions, the combination of onshore flow and terrain enhancement will likely contribute to maximum rainfall amounts. ...Precipitation in Mexico... Southern Veracruz: a maxima of of 30 - 60mm on Thursday... a maxima of 15-20mm on Friday. Tabasco, Chiapas, and Chiapas: a maxima of 15 - 25mm on Thursday. Northwest Yucatan Peninsula: a maxima of 15 - 25mm on Thursday. Yucatan Peninsula: a maxima of 15 - 20 on Friday ... and a maxima of 20 - 35mm on Saturday ...Central America... A weak ridge over the basin favors the trade wind over the Caribbean. Easterly trades and Caribbean low-level jet will favor intermittent showers in northeastern Honduras, Belize and Panama. The interaction with topography can further influence local maxima of rainfall in the region. ...Precipitation in Central America... The following maxima are expected:Belize: maxima in the range of 15 - 20 mm on friday and saturdayÂNorthern Honduras: maxima of 15-25mm on Thursday, friday and saturdayÂThe Caribbean basin of west PanamÃ: a maxima of 20-35mm on Thursday. A maxima of 10mm on Friday and SaturdayÂThe Pacific basin of west PanamÃ: a maxima of 15 - 20mm on Thursday.East PanamÃ: a maxima of 15-20 on ThursdayCosta Rica: a maxima of 15 - 20mm on Friday ...Synoptic conditions over tropical South America... The nocturnal low-level jet over central northern South America will continue to weaken... resulting in a reduction of the dry areas and an increase in light rainfall across the region. A region of interest is Ecuador and far southwest Colombia, where warm SST and the pacific ITCZ are stimulating diurnal convection in the pacific basins.overall upper levels seems to provide enough support for deep convection. The onshore flow at lower levels along and south of the pacific ITCZ will become more perpendicular by friday...this could enhance the increase in moisture over Ecuador and southwest of Colombia. Therefore...the following maxima are expected: Ecuador CoastÂ/ Southwest Colombia: A maxima of 25 - 50mm on Thursday... a maxima of 20-45mm on Friday and 30-60mm on Saturday. Northwest Colombia: A maxima of 20 - 40mm on Thursday and a maxima of 20 - 35mm on Saturday Northeast Colombia: maxima of 15 - 25mm on Thursday and Friday. And a maxima of 20 - 35mm on Saturday Inland Ecuador and Inland Colombia: a maxima of 20 - 35mm on Thursday and Friday and Saturday In the Atlantic basin...the ITCZ in combination of upper deiverngece will promoteÂrainfall accumulation... from Thursday into Saturday...the largest precipitation maxima around the Amapa. The following maxima are expected: Amapa: a maxima of 25 - 50mm on Friday and 20 - 40mm on Saturday. Guianas a maxima of 20 - 35mm on Thursday. The rest of the tropical south america precipitation maxima will be along the net ITCZ...with maxima of 20 - 60mm for the forecast cycle. The largest accumulation are expected on Saturday. For graphical information: https://www.wpc.ncep.noaa.gov/international/crb_day1-3.shtml Ledesma...(WPC)