Prognostic Meteorological Discussion
Issued by NWS
Issued by NWS
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680 FXCA20 KWBC 051932 PMDCA Tropical Discussion - International Desks NWS Weather Prediction Center College Park MD 232 PM EST Wed Nov 05 2025 Forecast Bulletin 05 November 2025 at 1930 UTC: Synopsis: An Easterly Wave is expected to form and arrive to the Lesser Antilles/Windward Islands on Friday evening, bringing precipitation to this region, Trinidad and Tobago, and the Guianas on Friday and Saturday. A low-level trough in the southern Gulf will produce light to moderate precipitation for the northern Yucatan Peninsula, and in isolated parts of northwest Cuba today and Thursday. In the Bahamas and Caribbean, a stationary front is expected to remain in place in the southern Bahamas for the next couple of days, before a low-level ridge aids in its eastward propagation. This ridge will aid in transporting moisture northward into central Bahamas on Friday, and is expected to bring moderate precipitation into the islands and parts of eastern Cuba early in the weekend. Mexico, Central America, the Bahamas, and the Caribbean: A low-level trough in the Gulf will bring light to locally moderate precipitation to the north coast of the Yucatan Peninsula in Mexico over the next two days. Low-level easterly flow of moisture is expected to move into the Gulf, just north of the Yucatan Peninsula today, with the heaviest rainfall occurring offshore in the Gulf. At the southern ends of the trough, however, weaker onshore easterly flow is expected in the north and central Yucatan Peninsula. Given most of the prolonged moisture will be located to the north of the Peninsula, most inland precipitation should be light, with locally heavier precipitation possible today and Thursday. The rest of Mexico will experience dry conditions throughout the remainder of the week. An upper- to mid- level ridge will move into central Mexico tonight from the Pacific, preventing any moisture from the mid-level trough over the Gulf from being able to enter from the east. In the Bahamas and Caribbean, a stationary front located in the southern Bahamas and Cuba will remain in place while weakening, due to the arrival of a low-level ridge which will aid in propagating the front eastward over the next few days. Meanwhile, the propagation of the ridge will aid in changing the remnant low-level flow regime in the southern Bahamas, from an easterly to a southeasterly flow, which is expected to reach the central Bahamas on Friday and Saturday. A subtle enhancement of upper-level divergence will occur offshore in the Atlantic, which will aid in the production of convection. The southeasterly and moist low-level flow will result in precipitation for parts of the Bahamas and eastern Cuba on Friday and Saturday, with a maximum of 15-25mm expected each day. In the Lesser Antilles, an Easterly Wave is expected to form from the ITCZ in the Atlantic tonight, and is forecast to propagate westward, bringing in substantial low-level moisture. The wave will then reach the Windward Islands on Friday evening, producing precipitation beginning on Friday night through Sunday as it passes through the islands. Precipitation will peak at around 15-30mm on Saturday. Tropical South America: A plume of moisture is expected to move through the northern coast of South America, including the Guianas, northeast Venezuela, and Trinidad and Tobago, today and Thursday. An upper-level ridge will be located offshore in the Atlantic, and the western periphery of the ridge will be located over the Guianas, causing upper-level divergence to be enhanced. This will aid in the production of convection for this region today and Thursday, and precipitation will peak at around 20-35mm. On Saturday, the arrival of the Easterly Wave to the Windward Islands will also bring precipitation to parts of eastern Venezuela and Trinidad and Tobago. Precipitation amounts up to 15-20 are expected for Venezuela and Trinidad and Tobago on Saturday. In the rest of South America, precipitation will continue to be caused by local, diurnal, and orographic effects, with easterly flow from the Amazon providing the fuel for moisture over the next three days. The formation of the Panamanian Low will change the low-level flow into western Colombia over the next two days, with the seasonable onshore flow expected to cease during this time. With this change, western Colombia will see a reprieve from heavy precipitation, with 15-30mm expected today and 15-25mm expected Thursday. Positions of Tropical/Easterly Waves Initialized at 12 UTC TYP SOF INIT 06/00 06/12 07/00 07/12 08/00 08/12 09/00 EW 11N 40W 43W 46W 48W 51W 53W 56W 60W EW 12N 50W 52W 54W 56W 58W 60W 62W 64W EW 20N 66W 68W 71W 73W 75W ---------- For the latest available charts please visit: https://www.wpc.ncep.noaa.gov/international/crb_day1-3.shtml Blanco-Alcala...(WPC) $$