000 AXNT20 KNHC 042240 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 2300 UTC Thu Jun 4 2020 Tropical Weather Discussion for North America, Central America Gulf of Mexico, Caribbean Sea, northern sections of South America, and Atlantic Ocean to the African coast from the Equator to 32N. The following information is based on satellite imagery, weather observations, radar and meteorological analysis. Based on 1800 UTC surface analysis and satellite imagery through 2300 UTC. ...SPECIAL FEATURES... The center of Tropical Depression Storm Cristobal is near 17.5N 90.8W at 04/2100 UTC, moving east-southeast at 3 knots. The estimated minimum central pressure is 999 mb. The maximum sustained wind speeds are 30 knots with gusts to 40 knots. Some additional weakening is possible overnight. Re-intensification is expected to begin late Friday. On the forecast track, the center of Cristobal will move over extreme northwestern Guatemala and eastern Mexico tonight and Friday. The center is forecast to move back over the southern Gulf of Mexico late Friday, over the central Gulf of Mexico on Saturday, and approach the northern Gulf of Mexico coast Sunday and Sunday night. Currently, numerous moderate to scattered strong convection is noted over the Yucatan Peninsula. Similar convection is also seen in a band extending between San Andres Island and the coastal plains of Nicaragua, all the way to the NW to Cancun, Mexico. Scattered moderate convection is observed over portions of Guatemala, Belize, Honduras and El Salvador. Damaging and deadly flooding has already been occurring in portions of Mexico and Central America. Cristobal is expected to produce additional extreme rainfall amounts through the end of the week. The heaviest additional rainfall is expected over far southern Mexico and portions of the Yucatan Peninsula. This rainfall could cause widespread life-threatening flash floods and mudslides. Refer to products from your local weather office for more information. There is a risk of tropical storm force winds this weekend from Louisiana to the western Florida Panhandle and a risk of dangerous storm surge from Louisiana to the Florida Big Bend. These hazards, along with heavy rainfall, will arrive well in advance of and extend well east of Cristobals center. Interests along the northern coast of the Gulf of Mexico should monitor the progress of Cristobal. A tropical storm watch and a storm surge watch may be required for a portion of the area tonight or Friday. Please, read the latest HIGH SEAS FORECAST issued by the National Hurricane Center at website https://www.nhc.noaa.gov/text/MIAHSFAT2.shtml, and the latest Cristobal NHC Forecast/Advisory and Public Advisory at www.hurricanes.gov, for more details. ...EXCESSIVE RAINFALL IN CENTRAL AMERICA AND MEXICO... Tropical Depression Cristobal is part of a larger Central American Gyre circulation (CAG). Heavy rainfall and severe flooding have been impacting parts of Central America and southern Mexico during the last several days. Abundant tropical moisture in a southwesterly wind flow will continue to impact SE Mexico and northern Central America. More heavy rain are expected in the Mexican states of Campeche, Quintana Roo and Yucatan, as well as over El Salvador, with additional 5 to 10 inches of rain. Additional 2-4 inches are expected in Belize and the Mexican states of Tabasco, Veracruz and Oaxaca through Saturday. Please read bulletins and forecasts that are issued by your local or national meteorological service, for more details. ...TROPICAL WAVES... A tropical wave with axis along 37W and from 18N southward, is moving W at 15 kt. Isolated showers are noted where the wave axis meets the ITCZ. A second tropical wave is analyzed along 57W and from 17N southward, moving W at 10-15 kt. Scattered showers are near the wave axis, mainly S of 12N to the coast of South America. ...MONSOON TROUGH/ITCZ... The monsoon trough passes through the coastal sections of Guinea near 10N14W to 05N20W. The ITCZ extends from 05N20W to 04N34W, then resumes west of a tropical wave from 05N40W to 05N52W. Scattered moderate convection can be found N of the ITCZ from 04N to 08N between 25W-32W. GULF OF MEXICO... Please read the SPECIAL FEATURES section for details about Tropical Depression Cristobal. The pressure gradient between Cristobal and a ridge over the Gulf of Mexico supports an area of fresh to strong easterly winds across the southern Gulf, mainly S of 23N with seas of 8-10 ft roughly between 87W and 93W. As Cristobal moves back into the Gulf waters by late Fri, winds and seas will continue to increase across the Gulf region. The large circulation of Cristobal is forecast to dominate most of the Gulf region with the strongest winds and highest seas over the eastern semicircle. Diurnal heating, combined with a SE wind flow along the western periphery of the Bermuda high, and a diffluent pattern aloft continues to support shower and thunderstorms over most of the Florida Peninsula. Scattered to numerous showers and thunderstorms will again be possible over South Florida on Friday along with heavy rainfall. A Flood Watch is in effect for South Florida through Fri morning. CARIBBEAN SEA... A broad area of low pressure, known as the Central American Gyre, will persist over northern Central America and southern Mexico for the next few days. Please, see the Special Features section for more details. This is also forecast to produce scattered showers and thunderstorms in the NW Caribbean through at least Sat. The most recent scatterometer data indicated fresh to strong SE winds over the western Caribbean, including the Gulf of Honduras. As tropical cyclone Critobal moves back into the Gulf of Mexico waters by late Fri, the pressure gradient will tighten between Cristobal and the Atlantic high pressure. As a result, strong southeast winds and building seas will continue in the Gulf of Honduras and east of Yucatan Peninsula through Sat night. Winds may reach gale force in and near the Yucatan Channel Fri through most of Sat along with building seas of 15-17 ft. Fresh to strong trade winds will continue over the central Caribbean through early Sat. Fresh to strong southerly winds could affect the Isle of Youth and western Cuba Fri and Sat. A diffluent pattern aloft is helping to induce some convective activity over Cuba. As previously mentioned, a band of showers and thunderstorms is over the western Caribbean. Elsewhere, patches of low level moisture, embedded in the trade wind flow, prevail. ATLANTIC OCEAN... A couple of tropical waves are between Africa and the Lesser Antilles. Refer to the Tropical Waves section above for details. A stationary front extends from 31N47W to 25N60W to 26N70W. This front is forecast to slowly dissipate tonight into Fri. Convection is limited in association with this front. High pressure north of the front will support moderate to fresh trade winds, mainly north of Hispaniola, through Sat before diminishing slightly Sun through Mon. Farther E, a low pressure of 1008 mb is spinning between the Azores and the Madeira Islands with a trough extending into the forecast area to near 28N27W. Some shower activity is around the low center. $$ GR