000 AXNT20 KNHC 082213 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 613 PM EDT Wed Jul 8 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 2200 UTC. ...SPECIAL FEATURES... A broad area of low pressure located near the coast of northeastern South Carolina continues to produce a large area of disorganized showers and thunderstorms over the adjacent Atlantic waters and portions of eastern North Carolina. The low is expected to move northeastward near or just offshore of the North Carolina Outer Banks on Thursday, and then turn north-northeastward and move along the mid-Atlantic coast Friday. Environmental conditions are expected to be conducive for development, and a tropical or subtropical cyclone is likely to form within the next day or so. Regardless of development, the system is expected to produce locally heavy rainfall that could cause some flash flooding across portions of eastern North Carolina, the coastal mid-Atlantic, and southern New England during the next few days. Gusty winds are also possible along the North Carolina Outer Banks through Thursday and along the mid-Atlantic and southern New England coasts Friday and Saturday. Interests in these areas should monitor the progress of this system and refer to products from your local National Weather Service office. The chance of formation into a tropical cyclone, during the next 48 hours, is high. Please see the Tropical Weather Outlook, at www.hurricanes.gov, for more details. ...TROPICAL WAVES... A tropical wave is along 39W/40W S of 19N, moving W at 10-15 kt. Saharan air and an associated low level wind surge have moved well ahead of this wave, and can be seen from 10N to 22N, across the Atlantic Ocean to the Lesser Antilles. Scattered moderate convection is noted from 04N-10N between 37W-46W. A tropical wave is along 66W/67W from central Venezuela to Puerto Rico, moving W at around 15 kt. Scattered moderate and isolated strong convection is noted from 19N-22N between 66W-70W, with similar convection noted across the majority of Hispaniola. A tropical wave is along 78W from eastern Cuba to across Jamaica to near the Colombia/Panama border, moving W at 10-15 kt. Scattered moderate and isolated strong convection is noted from 09N-15N between 75W-84W, with similar convection noted over Jamaica, NW Colombia, and portions of Central America. A tropical wave is along 89W from Belize southward to across portions of Central America, moving W at 10-15 kt. This wave will completely move into the Pacific basin overnight. No significant convection is noted outside of the Pacific basin. ...MONSOON TROUGH/ITCZ... The monsoon trough passes from near the Guinea/Guinea-Bissau border to 09N23W. The ITCZ extends from 09N23W to 09N37W, then resumes W of a tropical wave from 09N41W to the coast of Brazil near 02N52W. Scattered moderate and isolated strong convection is noted from 06N-13N between 15W-23W, likely associated with the next tropical wave. Similar convection is noted from 05N-07N between 31W-34W. GULF OF MEXICO... A 1019 mb high is centered over the E Gulf of Mexico near 26N87W. Satellite and radar imagery indicate isolated to scattered showers and thunderstorms over portions of the Florida peninsula, and across southern Alabama and Mississippi. Similar activity is noted over eastern Cuba toward the Yucatan Channel. Otherwise, fairly tranquil weather is noted over the waters. Light to gentle winds are noted near the high center per afternoon scatterometer data, with moderate to locally fresh return flow elsewhere. Seas are 3 ft or less E of 90W and 4-6 ft W of 90W per afternoon altimeter and ship/buoy data. Surface high pressure will remain centered over the Gulf through the weekend with the high center fluctuating between the NW and NE basin. This will allow for the continuation of moderate to fresh return flow west of 90W and moderate westerly winds across NE portions of the basin. Scattered showers are forecast for the NE and SE portions of the basin Fri and Sat as associated with a broad area of low pressure currently centered over North Carolina. CARIBBEAN SEA... A 1009 mb low pressure area is near 10N78W along a tropical wave. with two other tropical waves impacting the basin as is described above. Otherwise, high pressure prevails N-NE of the basin. Fresh to strong trade winds are noted in the S-central Caribbean along with 5-7 ft seas. Moderate to fresh trades are noted elsewhere, except gentle in the NW Caribbean. Seas are 4-6 ft elsewhere in the Caribbean, except 3 ft or less over the majority of the NW Caribbean. Atlantic high pressure extending to the northern Caribbean waters will allow the continuation of fresh to strong tradewinds in the S-central Caribbean increasing to near gale force Fri and Sat nights. Freshening winds, building seas and active weather accompanying the strong tropical wave along 78W will shift W across the basin through Fri. Strong winds will pulse at night in the Gulf of Honduras Fri night through the weekend. Another strong tropical wave will reach the tropical N Atlc waters Sat and move across the E Caribbean Sat night and Sun. ATLANTIC OCEAN... A surface trough is analyzed from 32N50W to 28N60W to 30N66W. Scattered showers are likely on either side of the trough within 120 nm. A cold front curls from offshore of the Carolinas to coastal Georgia. Scattered moderate and isolated strong convection is noted within 240 nm SE of the front. Moderate to fresh SW winds are noted N of 28N and W of 75W ahead of the front, with moderate to fresh SE flow N of Hispaniola. A 1028 mb high pressure is centered NE of the Azores near 40N25W with a ridge axis reaching SW-W through 32N38W all the way to near the northern Bahamas. Gentle winds prevail elsewhere N of 25N, with moderate to fresh trades elsewhere S of 25N. Scattered showers and thunderstorms associated with the front and area of low pressure over the SE United States will continue to affect the waters E and N of the Bahamas through the weekend. Surface ridging will dominate the remainder of the waters E of 70W. The pressure gradient between the low and the ridge will support moderate to fresh winds across most of the region, increasing to fresh to strong winds N of the Bahamas over the weekend. $$ Lewitsky