000 AXNT20 KNHC 242357 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 757 PM EDT Tue Sep 24 2019 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 2340 UTC. ...SPECIAL FEATURES... Tropical Storm Karen is centered near 18.5N 65.3W at 25/0000 UTC, or about 40 nm E of San Juan Puerto Rico, moving NE at 9 kt. Maximum sustained winds are near 40 kt gusting to 50 kt, and minimum central pressure is 1003 mb. Karen's squalls will continue to affect Puerto Rico and the Virgin Islands tonight before it pulls away to the north of those islands on Wednesday. Slow strengthening is forecast during the next couple of days. Numerous moderate with scattered strong convection extends outward from the center 30 nm NE quad, 240 nm SE quad, 180 nm SW quad and 90 nm NW quad. Puerto Rico radar shows that heavy rains cover the eastern half of Puerto Rico and the waters from 16N-18.5N between 65W-67W. Scattered moderate convection is also over the Dominican Republic. Please read the latest NHC forecast/advisory under AWIPS/WMO headers MIATCMAT2/WTNT22 KNHC for more details. Tropical Storm Jerry is centered near 31.3N 68.9W at 25/0000 UTC, or about 215 nm WSW of Bermuda, moving NNE at 4 kt. Maximum sustained winds are near 45 kt gusting to 55 kt, and minimum central pressure is 992 mb. The center of Jerry is expected to pass near Bermuda on Wednesday, where a Tropical Storm Warning is in effect. Gradual weakening is forecast during the next few days. No convection is present within 180 nm of Jerry's center. Scattered moderate convection is between 180 nm and 540 nm to the east and southeast of Jerry's center. Please read the latest NHC forecast/advisory under AWIPS/WMO headers MIATCMAT5/WTNT25 KNHC or www.hurricanes.gov for more details. Tropical Storm Lorenzo is centered near 12.8N 31.0W at 24/2100 UTC, or about 405 nm WSW of the southernmost part of the Cabo Verde Islands, moving WNW at 15 kt. Maximum sustained winds are near 55 kt gusting to 65 kt, and minimum central pressure is 997 mb. A west-northwest motion at a similar forward speed is expected through Thursday. Lorenzo is expected to strengthen to a hurricane tonight or on Wednesday. Numerous strong convection is within 90 nm of the center in the E semicircle, and 60 nm W semicircle. Scattered moderate convection is elsewhere within 300 nm of the center. Please read the latest NHC forecast/advisory under AWIPS/WMO headers MIATCMAT3/WTNT23 KNHC or www.hurricanes.gov for more details. Heavy rain event over Central America and Southeastern Mexico: The East Pacific monsoon trough extends from the SW Caribbean inland over the spine of Central America, across Nicaragua, Honduras, Guatemala, and westward to the Gulf of Tehuantepec. Southwesterly monsoonal flow is carrying abundant moisture from the tropical Pacific Ocean toward Central America. As a result, heavy rainfall is expected over Central America today through the week and into the weekend. By late this week and into the weekend, the greatest threat for heavy rainfall will migrate northwestward to areas from southern Guatemala to southern Mexico, including the Mexican states of Chiapas, Oaxaca and Guerrero. The heavy rains could lead to flash flooding and mudslides, especially in areas of mountainous terrain and areas near the Pacific coast. ...TROPICAL WAVES... An Atlantic Ocean tropical wave extends from 27N40W to 17N44W to 03N42W, moving W at 10 kt. Scattered moderate convection is from 22N-29N between 36W-43W. Scattered showers are from 12N-19N between 41W-47W. ...MONSOON TROUGH/ITCZ... The monsoon trough extends from the coast of Mauritania near 17N16W to 15N21W. The monsoon trough resumes west of T.S. Lorenzo from 10N36W to 07N42W. The ITCZ extends from 08N46W to 09N60W. Aside from the convection associated with Lorenzo and the tropical wave, isolated moderate convection is seen from 13N-18N between 20W-26W, including over the Cabo Verde Islands. GULF OF MEXICO... Upper level cyclonic wind flow covers the coasts of Texas, northeastern Mexico, and the western Gulf of Mexico west of 92W and north of 23N. Upper-level anticyclonic flow covers the Gulf east of a line from 29N91W to 20N96W. At the surface, high pressure of 1015 mb is near the Gulf Coast of southern Mississippi and SE Louisiana. A surface trough extends over the Yucatan Peninsula and south-central Gulf of Mexico from 24N89W to 19N90W. Scattered moderate to isolated strong convection is from 22N-25N between 89W-91W. Similar convection is inland over the eastern Yucatan Peninsula. Scattered showers are elsewhere in the Gulf south of 25.5N between 86W-91.5W. The surface trough will move slowly westward across the southwestern Gulf of Mexico during the next few days. This trough has a low chance of developing into a tropical cyclone before reaching northeastern Mexico late Fri or Sat. Scattered showers are also noted in the south-central Bay of Campeche, south of 21N between 92.5W-96W. Isolated showers are also seen near the lower Texas coast. The driest air in the Gulf right now can be found in the eastern Gulf, east of a line from Mobile Alabama to 23N85W, where little to no cloud cover is observed. The ASCAT pass from late Tuesday morning showed gentle anticyclonic winds in the northern Gulf, with moderate winds in the central and SE Gulf. CARIBBEAN SEA... An E-W surface trough has been added to the analysis at 21Z across the northern Caribbean Sea extending from the eastern tip of Cuba to 19N77W to 21N83W. Water vapor and TPW loops show a sharp moisture gradient along a line from 21N75W to 21N82W to 23N86W, with dry air north of this line and moist air south of the line. Scattered moderate convection is from 15N-21.5N between 72W-80W. Scattered showers and tstorms are also in the Yucatan Channel and from 20N-23N between 82W-87W. A surface trough over the Yucatan Peninsula is enhancing scattered moderate convection over the eastern Yucatan Peninsula. Scattered moderate convection is also over northern Colombia and the waters south of 12.5N between 72W-74W. ASCAT from late Tuesday morning showed that gentle winds cover most of the Caribbean Sea west of 69W. Tropical Storm Karen will move north of the Virgin Islands and Puerto Rico, exiting the Caribbean Sea late tonight. By sunrise Wednesday morning, all winds of 20 kt or greater associated with Karen's circulation will have exited the Caribbean Sea. A fairly weak pressure pattern with light and variable winds and low seas will prevail across the western and central Caribbean Sea through Thursday. More typical conditions and trade winds are forecast to return by the end of the week. A tropical wave is expected to reach the Tropical N Atlantic Ocean by the end of the week, moving through the eastern Caribbean Sea for the start of the weekend. ATLANTIC OCEAN... An elongated upper-level low is located to the southwest of Jerry. This has induced strong southwesterly shear over Jerry, causing the tropical storm to become devoid of any convection. A large area of scattered moderate convection is located to the east of Jerry, seen from 25N-32N between 56W-66W. Farther east, an upper- level low prevails just north of the area centered near 33N46W, with a tail of mid to upper-level moisture wrapping well to the southeast and south of the upper-low. The moisture extends into the northern end of the tropical wave that begins near 27N40W. Scattered moderate convection is from 22N-32N between 35W-44W. On the west side of the upper-low, scattered moderate convection is from 29N-32N between 47W-50W. Tropical Storm Jerry is near 31.3N 68.9W, 992 mb, at 8 PM EDT, moving NNE at 4 kt. Maximum sustained winds are near 45 kt with gusts to 55 kt. Jerry is devoid of convection and will continue to weaken, as it moves to near 33N66W Wed afternoon. Tropical Storm Karen is near 18.5N 65.3W, 1003 mb, at 8 PM EDT, moving NE at 9 kt. Maximum sustained winds are near 40 kt with gusts to 50 kt. Karen will move to near 22N65W Wed afternoon, 26N 63.5W Thu afternoon, and 27N62W Fri afternoon while strengthening slightly. Tropical Storm Lorenzo is near 12.8N, 31.0W, 997 mb, at 5 PM EDT, moving WNW at 15 kt. Maximum sustained winds are near 55 kt with gusts to 65 kt. Lorenzo will strengthen to a hurricane tonight or early Wed, then move to near 16N40W Thu afternoon, and to near 22N45W Saturday afternoon, likely as a large and powerful hurricane. $$ Hagen