000 AXNT20 KNHC 301000 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 805 AM EDT Thu Jul 30 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 0600 UTC surface analysis and satellite imagery through 1000 UTC. ...SPECIAL FEATURES... The center of Tropical Storm ISAIAS, at 30/0900 UTC, is near 17.2N 67.9W. This position also is about 90 nm/165 km to the WSW of Ponce in Puerto Rico; and about 150 nm/255 km to the SE of Santo Domingo in the Dominican Republic. ISAIAS is moving NW, or 305 degrees, at 18 knots. The estimated minimum central pressure is 1003 mb. The maximum sustained winds are 50 knots with gusts to 60 knots. Precipitation: scattered moderate to strong is within 420 nm of the center in the N semicircle, and within 240 nm of the center in the S semicircle. The current forecast moves the center of ISAIAS across Hispaniola later today, and past the southeastern Bahamas on Friday. Tropical storm-force winds extend outward, up to 360 nm/, mainly to the NE of the center. Please read the latest NHC Public Advisory at https://www.nhc.noaa.gov/text/MIATCPAT4.shtml, and the Forecast/Advisory at https://www.nhc.noaa.gov/text/MIATCMAT4.shtml, for more details. ...TROPICAL WAVES... A tropical wave is along 24W, from 20N southward, moving W at 15 knots. Precipitation: nearby precipitation is associated with the monsoon trough. A tropical wave is along 39W, from 20N southward, moving at W 10 to 15 knots. Precipitation: nearby precipitation is associated with the monsoon trough. A tropical wave is along 81W, from 20N southward, moving W at 15 knots. Precipitation: isolated moderate is within 60 nm of the wave axis. ...MONSOON TROUGH/ITCZ... The monsoon trough passes through the coastal sections of Senegal near 16N17W, to 09N36W, to 07N50W. Precipitation: widely scattered moderate and isolated strong is within 360 nm to south of the monsoon trough. GULF OF MEXICO... Upper level cyclonic wind flow covers the Yucatan Peninsula and the SW corner of the Gulf of Mexico, associated with an upper level inverted trough. A tropical wave along 94W south of 19N is exiting the area. Precipitation: isolated moderate covers the areas from 22N southward between the Yucatan Peninsula and 94W. Tropical Storm Isaias near 17.2N 67.9W 1003 mb at 5 AM EDT moving NW at 18 kt. Maximum sustained winds 50 kt gusts 60 kt. Isaias will remain east of the region through the weekend. A ridge will dominate the rest of the Gulf of Mexico through Friday, supporting mainly gentle to moderate return flow. CARIBBEAN SEA... A Caribbean Sea tropical wave is along 81W, from 20N southward, moving W at 15 knots. Isolated moderate convection is from 13N southward and 75W westward, in the SW corner of the Caribbean Sea. Elsewhere, scattered moderate isolated strong is from 20N southward and 82W westward, in the coastal waters of Honduras, and inland in Belize and Guatemala. The monsoon trough is along 09N/10N, from Colombia along 74W westward, to the coastal waters of Central America from Nicaragua southward. Scattered moderate convection is from 10N southward and 75W westward, in the SW part of the Caribbean Sea. Tropical Storm Isaias near 17.2N 67.9W 1003 mb at 5 AM EDT moving NW at 18 kt. Maximum sustained winds 50 kt gusts 60 kt. Isaias will move inland to 18.8N 70.2W this afternoon, 20.6N 72.9W Fri morning, 22.3N 75.5W Fri afternoon, 24.0N 77.9W Sat morning, 25.5N 79.2W Sat afternoon, and 27.3N 80.0W Sun morning. Tropical storm conditions will continue in the Virgin Islands and Puerto Rico early this morning, then reach portions of the Dominican Republic and Haiti later today. ATLANTIC OCEAN... The GFS model for 250 nm, and current water vapor satellite imagery, show that an anticyclonic circulation center is in the Atlantic Ocean, about 600 nm to the ENE of T.S. ISAIAS. The GFS model for 250 nm, and current water vapor satellite imagery, show that a trough extends from SE Cuba toward Bermuda. No significant deep convective precipitation is associated with the trough. Multi-layered clouds and precipitation, that are accompanying T.S. ISAIAS, are within 400 nm to the E and ESE of the trough. Broken to overcast multi-layered clouds, and scattered moderate convection, covers the Atlantic Ocean from 10N to 30N between 54W and 73W. Tropical Storm Isaias near 17.2N 67.9W 1003 mb at 5 AM EDT moving NW at 18 kt. Maximum sustained winds 50 kt gusts 60 kt. Isaias will move inland to 18.8N 70.2W this afternoon, 20.6N 72.9W Fri morning, 22.3N 75.5W Fri afternoon, 24.0N 77.9W Sat morning, 25.5N 79.2W Sat afternoon, and 27.3N 80.0W Sun morning. Gale-force winds extend more than 400 nm north and northeast of Isaias into the Atlantic. Tropical storm conditions are possible NE of Isaias over a large portion of the SW North Atlantic as the center of Isaias moves from south of Puerto Rico, across Hispaniola, toward southern Florida and the Bahamas. $$ mt/dbm