000 AXNT20 KNHC 190506 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 0605 UTC Mon Sep 19 2022 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 31N. The following information is based on satellite imagery, weather observations, radar and meteorological analysis. Based on 0000 UTC surface analysis and satellite imagery through 0450 UTC. ...SPECIAL FEATURES... Hurricane Fiona is centered near 18.0N 68.1W at 19/0300 UTC or 40 nm SSE of Punta Cana, Dominican Republic, moving WNW at 9 kt. Estimated minimum central pressure is 982 mb. Maximum sustained wind speed is 75 kt with gusts to 90 kt. Seas of 12 ft or greater extend out 120 nm in the E semicircle and 60 nm W semicircle. Peak seas are currently 20 ft in the Mona Passage. Seas are expected to build to 38 ft by the time Fiona strengthens to a major hurricane over the Atlantic late Tue. Numerous strong convection associated with the core of Fiona extends outward to 45 nm E semicircle and 60 nm W semicircle. Numerous moderate scattered strong convection is located in a north-south oriented band to the east of Fiona from 15N-20N between 64.5W-67W, including over Puerto Rico. Scattered moderate convection is elsewhere within 270 nm E semicircle, 90 nm SW quadrant and 180 nm NW quadrant. Latest Doppler radar shows very heavy rain continuing over much of Puerto Rico. At least two rain gauges measured over 20 inches of rain in the past 24 hours, and catastrophic flooding has prompted dozens of water rescues on Saturday and Saturday night in Puerto Rico. On the forecast track, the center of Fiona will move over the eastern portions of the Dominican Republic today, and near or to the east of the Turks and Caicos Islands on Tuesday. Strengthening is expected during the next 48 hours. Swells generated by Fiona are affecting the Leeward Islands, the northern Windward Islands, the Virgin Islands, Puerto Rico, the northern coast of the Dominican Republic, the Turks and Caicos Islands, and the southeastern Bahamas. These conditions could cause life- threatening surf and rip current conditions. 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 NHC Forecast/Advisory and Public Advisory at www.hurricanes.gov for more details. ...TROPICAL WAVES... An Atlantic Ocean tropical wave extends its axis along 44W from 04N-15N, moving west at 15 to 20 kt. Scattered showers are noted along the northern half of the wave from 09N to 13N between 38W and 48.5W. An Atlantic Ocean tropical wave extends its axis along 54W from 07N-20N, moving W at 10-15 kt. A surface trough extends N of the wave to 26N52W. Scattered showers are noted along and within 360 nm E of the wave axis from 05N-13N. Scattered showers are also along and within 180 nm E of the trough axis. ...MONSOON TROUGH/ITCZ... The monsoon trough passes through the coast of Senegal near 14N17W to 1012 mb low pressure near 09N26W to 09N44W. The ITCZ extends from 09N45W to 09N53W. Scattered moderate to strong convection is noted from 06N-10N between 27W-30W. GULF OF MEXICO... Weak surface ridging over the eastern United States extends southwestward into the Gulf of Mexico, supporting mainly moderate easterly winds across the central and western Gulf. Recent observations from buoys and oil platforms show fresh NE winds over the NE Gulf. Fresh to locally strong NE winds are west of the Yucatan Peninsula, over the eastern Bay of Campeche. Recent buoy data indicate seas of 2 to 3 ft prevail across the Gulf, but seas as high as 4 ft may be occurring in a few spots. Scattered showers and isolated tstorms are noted over the southwest Gulf of Mexico, south of 25N and west of 91W. Similar activity is noted in the eastern portion of the Straits of Florida, east of 81.5W, due to a surface trough in the area. The rest of the Gulf remains under fairly tranquil weather conditions. For the forecast, high pressure over the southeastern U.S. will maintain gentle to moderate easterly breezes and slight seas the next few days. CARIBBEAN SEA... Please see the section above for information on Hurricane Fiona. Outside of convection associated with Fiona, scattered showers and thunderstorms are noted north of Honduras, from 15.5N-18.5N between 81W-88W. Scattered moderate isolated strong convection associated with the east Pacific monsoon trough is noted near the coasts of western Venezuela, Colombia and eastern Panama, mainly south of 13N between 68W-79W. Fresh NE winds are likely occurring in the Windward Passage, while recent ASCAT data indicate that gentle trades prevail elsewhere. The area of winds over 20 kt and seas over 7 ft associated with Fiona is confined to areas north of 15N between 63.5W-71W. Seas are 1-3 ft cover the W Caribbean, west of 78W. Seas are 4-6 ft elsewhere in the E Caribbean, outside of Fiona. For the forecast, Hurricane Fiona will track near the eastern and northern coasts of the Dominican Republic today and continue northwestward to near or east of the Turks and Caicos Islands on Tue while strengthening. Residual swell over the eastern Caribbean from Fiona will slowly subside early this week. ATLANTIC OCEAN... Refer to the sections above for details on Hurricane Fiona and the tropical waves moving across the basin. A 1017 mb surface low pressure near 27.5N46W is along a surface trough extending from 25N47W to 27N46W. A recent ASCAT pass shows fresh winds associated with this low. An upper-level low centered near 25N47W is supporting this surface trough. Scattered moderate convection is noted from 28N-31N between 43W-48W. The system has a low chance of tropical cyclone formation during the next 48 hours while it moves generally northward. A surface trough extends across the Florida Peninsula from 31N81W to the Straits of Florida near 23N81.5W. Scattered showers and tstorms are within 210 nm E of the trough axis, or from 22.5N to 31N between 77W and 81W. A weak stationary front extends from 31N61W to 29N63W with isolated showers to its east. High pressure ridging prevails elsewhere, anchored by a 1023 mb high centered near 34N34W. Mostly moderate winds and seas of 4-6 ft prevail across most of the Atlantic. The exception is near Hurricane Fiona. Winds over 20 kt and seas of 8 ft or higher are located south of 23N between 63W-70W, in association with Fiona. An area of fresh trade winds is noted on scatterometer from 12N-20N between 28W-48W. For the forecast west of 55W, Fiona will move to near 20.4N 70.0W this evening, strengthen to a major hurricane Tue evening near 23.3N 71.1W, near 26.4N 70.5W Wed evening, then to near 31.2N 67.4W Thu evening. Fiona will move well northeast of the area through Fri night. High pressure will build in the wake of Fiona. $$ Hagen