000 AXNT20 KNHC 190546 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 146 AM EDT MON SEP 19 2016 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 0000 UTC surface analysis and satellite imagery through 0515 UTC. ...SPECIAL FEATURES... Tropical Storm Karl is centered near 18.3N 46.3W at 19/0300 UTC or about 890 nm E of the Leeward Islands moving W at 13 kt. Estimated minimum central pressure is 1006 mb. Maximum sustained wind speed is 35 kt with gusts to 45 kt. Widely scattered moderate convection is from 17N-21N between 42W-47W. See latest NHC Forecast/Advisory under AWIPS/WMO headers MIATCMAT2/WTNT22 KNHC for more details. Post-Tropical Cyclone Julia is centered near 32.2N 78.4W at 19/0300 UTC or about 95 nm S-SE of Myrtle Beach South Carolina and about 170 nm S-SW of Cape Lookout North Carolina moving NW at 6 kt. Estimated minimum central pressure is 1011 mb. Maximum sustained wind speed is 25 kt with gusts to 35 kt. Isolated moderate convection is from 30N-32N between 76W-78W. See latest NHC Forecast/Advisory under AWIPS/WMO headers MIATCMAT1/WTNT21 KNHC for more details. Tropical wave extends from 08N24W to 19N24W moving W at 5-10 kt. A 1007 mb low is analyzed along the wave axis near 13N and remains embedded within the Monsoon Trough as a broad low-level monsoonal gyre from 08N-21N between 17W-35W. Widely scattered moderate convection is from 07N-17N between 19W-29W. See the latest NHC Tropical Weather Outlook under AWIPS/WMO Headers MIATWOAT/ABNT20 KNHC for more details. ...TROPICAL WAVES... Tropical wave extends from 11N65W to 21N64W moving W at 15 kt. The wave remains within broad 700 mb troughing over the Caribbean Sea between 65W-76W and is embedded within an area of maximum low-level moisture as noted in Total Precipitable Water imagery. The wave is expected to remain on the eastern periphery of an upper level low noted on water vapor imagery centered near 14N68W. Isolated moderate convection is from 10N-16N between 63W-69W. ...ITCZ/MONSOON TROUGH... The Monsoon Trough extends from the African coast near 17N16W to 13N24W to 10N36W. Aside from convection associated with the tropical wave along 24W...widely scattered moderate convection is from 06N-11N between 11W-15W. ...DISCUSSION... GULF OF MEXICO... An upper level ridge anchored over western Mexico extends a ridge axis eastward over the Gulf basin through 26N97W to over the northern Florida peninsula near 29N82W. The ridging aloft supports a pair of high pressure centers...one a 1017 mb high centered near 27N86W and the other a 1015 mb high centered near 28N93W. Water vapor imagery also indicates a middle to upper level shortwave trough moving over the lower Mississippi River valley this evening that is supportive of a weak surface trough boundary analyzed from 30N90W to 27N91W generally in the area between the two surface highs. Isolated showers and tstms are occurring across a portion of the north-central Gulf waters N of 25N between 88W-92W. Given the overall tranquil conditions with high pressure in place... gentle to moderate anticyclonic winds are expected through Tuesday. CARIBBEAN SEA... An upper level low is centered over the eastern Caribbean near 14N68W that supports surface trough analyzed from 14N68W through the Mona Passage to 20N67W. Isolated showers are occurring from 14N-19N between 65W-70W...including portions of Puerto Rico this evening. To the immediate east...a tropical wave is noted along 65W that falls beneath the eastern periphery of the upper level low. Low-level moisture convergence and middle to upper level lifting dynamics are supporting isolated showers and tstms across the eastern Caribbean S of 16N between 61W-68W. Otherwise... farther west...an upper level ridge is anchored over the western Caribbean near 15N83W with ample diffluence aloft generating scattered showers and tstms across portions of northern Nicaragua...Honduras...El Salvador...and the Gulf of Honduras waters S of 17N W of 84W. Finally...moderate to occasional fresh trades persist with the strongest of these trades generally remaining across south-central portions of the basin. ...HISPANIOLA... Isolated showers are noted across portions of the island as an upper level low is centered across the Caribbean Sea near 14N68W. A surface trough is analyzed north-south across the Mona Passage and is expected to drift west across the island on Monday. Immediately following the upper level low...a tropical wave along 65W will continue to provide increased cloudiness and higher probabilities of precipitation through the first half of the week. ATLANTIC OCEAN... Aside from Post-Tropical Cyclone Julia in the SW North Atlc...a broad area of weaker surface pressures are noted focused on a surface trough analyzed from 31N60W SW to 28N67W to 23N72W. Scattered showers and tstms are occurring in the vicinity of 29N64W with isolated showers and tstms occurring elsewhere N of 26N between 57W-66W...and from 27N-32N between 70W-78W. Otherwise...aside from Tropical Storm Karl and the special features tropical wave along 24W...the remainder of the central and eastern Atlc is under the influence of a surface ridge anchored by a 1035 mb high centered well north of the discussion area near 43N29W. For additional information please visit http://www.hurricanes.gov/marine $$ HUFFMAN