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| #1003567 (Received by flhurricane at: 10:39 PM 04.Jun.2020) TCDAT3 Tropical Depression Cristobal Discussion Number 14 NWS National Hurricane Center Miami FL AL032020 1000 PM CDT Thu Jun 04 2020 Cristobal is not very well organized at the moment as the center of the circulation remains inland over northern Guatemala and southeastern Mexico. Satellite images and radar data from Sabancuy, Mexico, indicate that the associated showers and thunderstorms lack banding features and the center is becoming less distinct. The initial intensity is held at 30 kt, but these winds are likely occurring over water well to the north and east of the center. The depression is moving slowly to the east as it nears the completion of a cyclonic loop around the Central American gyre that it has been embedded within. The models show the depression turning northward soon on the west side of a subtropical ridge over the western Atlantic. This should take Cristobal back over the southern Gulf of Mexico waters by Friday night, and across the central and northern Gulf of Mexico over the weekend. A fairly progressive ridge moving across the central U.S. could cause Cristobal to turn to the left slightly as it moves across the Gulf coast late this weekend and early next week. There remains a fair amount of spread in the model solutions, with the GFS being the fastest and farthest east and the ECMWF much slower and to the west. The NHC track forecast is between those scenarios and lies near the various consensus aids, which typically have the lowest errors. Cristobal is forecast to remain inland for another 12 to 24 hours, so little change in strength is anticipated during that time. After the system moves back over water, gradual strengthening seems likely until Cristobal reaches the northern Gulf coast. The intensification rate should be slow since Cristobal is a large system and will be moving into an environment of moderate wind shear and some dry air. The NHC intensity forecast is largely an update from earlier and lies roughly near the middle of the guidance envelope. Cristobal is expected to have a broad and asymmetric wind field as it approaches the northern Gulf coast. Given the expected environmental conditions, the strongest winds, highest storm surge, and heaviest rains could be well removed from the center of circulation. Therefore, it is important that users do not focus on the exact forecast path of the center of the cyclone. For more information on the potential impacts, see the Key Messages below. Key Messages: 1. 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, while also extending along the Pacific coast from Chiapas to Guatemala and El Salvador. This rainfall could cause widespread life-threatening flash floods and mudslides. Refer to products from your local weather office for more information. 2. Cristobal is forecast to re-emerge over the southern Gulf of Mexico on Friday and move northward over the central and northern Gulf of Mexico over the weekend. 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 will arrive well in advance of and extend well east of Cristobal`s center. Storm surge and tropical storm watches will likely be issued for a portion of the U.S. Gulf Coast on Friday. 3. Heavy rainfall will spread into portions of the Gulf Coast from east Texas to Florida this weekend into early next week, with areas of flash flooding possible. FORECAST POSITIONS AND MAX WINDS INIT 05/0300Z 17.8N 90.4W 30 KT 35 MPH...INLAND 12H 05/1200Z 19.1N 90.1W 25 KT 30 MPH...INLAND 24H 06/0000Z 20.9N 90.2W 30 KT 35 MPH...NEAR THE COAST 36H 06/1200Z 22.5N 90.6W 40 KT 45 MPH...OVER WATER 48H 07/0000Z 24.3N 90.5W 45 KT 50 MPH...OVER WATER 60H 07/1200Z 26.3N 90.4W 50 KT 60 MPH...OVER WATER 72H 08/0000Z 28.3N 90.9W 50 KT 60 MPH...OVER WATER 96H 09/0000Z 32.6N 92.7W 30 KT 35 MPH...INLAND 120H 10/0000Z 37.3N 90.8W 25 KT 30 MPH...INLAND $$ Forecaster Cangialosi |