000 AXNT20 KNHC 101741 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 141 PM EDT MON OCT 10 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 1200 UTC surface analysis and satellite imagery through 1715 UTC. ...SPECIAL FEATURES... Tropical Storm Nicole is less organized than yesterday, but the forecast calls for strengthening tonight and Tuesday. At 10/1500 UTC...Nicole is centered near 25.7N 65.2W or about 455 nm S of Bermuda moving N at 6 kt. A turn toward the north-northwest is expected by tonight, followed by a turn toward the northwest on Tuesday. Estimated minimum central pressure is 992 mb. Maximum sustained wind speed is 50 kt with gusts to 60 kt. Slow strengthening is expected to begin by tonight, and Nicole is forecast to become a hurricane on Tuesday. Scattered moderate isolated strong convection is from 24N-27N between 63W- 67W. See latest NHC Forecast/Advisory under AWIPS/WMO headers MIATCMAT5/WTNT25 KNHC for more details. ...TROPICAL WAVES... A tropical wave is relocated farther E based on satellite imagery, an Ascat pass and observations from buoy 41041 located near 14N46W. The wave now extends from 07N46W to 15N45W. This feature shows up well as a low amplitude moisture surge on Total Precipitable Water imagery and satellite derived winds. Only isolated moderate showers are on either side of the wave axis. This wave will be near the Lesser Antilles by Wednesday night. A tropical wave is moving across the eastern Caribbean and extends from 06N65W to 16N64W moving W at 15 kt. The wave coincides with abundant low-level moisture as noted on Total Precipitable Water imagery. An Ascat pass indicates the wind shift associated with the wave axis. A large area of showers and thunderstorms is near the southern end of the wave axis affecting mainly the eastern part of Venezuela. This wave is expected to reach the central Caribbean on Tuesday and the western Caribbean by Thursday. Another tropical wave is over the Caribbean Sea and extends from 08N78W to 16N77W moving W at 15 kt. The wave coincides with 700 mb troughing between 75W-80W...and a maximum in 850 mb relative vorticity along the wave axis near 13N. an area of showers with embedded thunderstorms is ahead of the wave axis from 12N-14N between 77W-80W. This wave is forecast to move into Central America by Tuesday night. ...ITCZ/MONSOON TROUGH... The Monsoon Trough extends from the African coast near 10N14W to 10.5N21W to 10N24W. The Intertropical Convergence Zone axis extends from 10N24W to 08N30W to 09N45W. Scattered moderate and isolated strong convection is from 05N-08N between 16W-28W, and from 05N-09N between 40W-46W. ...DISCUSSION... GULF OF MEXICO... A surface trough is analyzed across the SW Gulf and extends from 23N89W to the Bay of Campeche near 19N93W. This trough was associated with a frontal boundary that crosses South Florida yesterday. Th trough is generating isolated to scattered showers and thunderstorms. The northern Gulf is under the influence of a ridge anchored by a high over NE United States. Moderate to fresh NE-E winds are noted between the ridge and the trough. The high press will support moderate to fresh NE-E winds over the central and eastern Gulf through likely Friday. Aloft...a trough extends over the western Gulf while a ridge is noted over the eastern Gulf. Southwesterly flow ahead of the trough axis is transporting abundant mid-upper level moisture across Central America and the Yucatan Peninsula. This flow is also enhancing convection near the surface trough. CARIBBEAN SEA... As previously mentioned, a pair of tropical waves are moving westward across the Caribbean Sea. Please, see Tropical Waves section for details. A ridge, extending from Florida and the Eastern Gulf, covers the NW Caribbean. A recent Ascat pass provides observations of moderate to fresh NE winds in the lee of Cuba, particularly N of 20N between 78W and 82W. Similar wind speeds are also noted north of Cuba across the Straits of Florida. These winds are transporting low-level clouds with embedded light showers. Low-topped trade wind showers are noted over the most of the basin. An area of showers and isolated thunderstorms is affecting the Lesser Antilles and regional waters. This convective activity is associated with an upper-level low centered over the Windward Islands. An upper-level anticyclone located over the central Bahamas extends a ridge across much of the Caribbean W of 70W. ...HISPANIOLA... Moisture is forecast to increase across the islands as a trough extending from T.S. Nicole remains over the area. This will favor scattered showers and isolated thunderstorms over the next few days. ATLANTIC OCEAN... T.S. Nicole is centered near 25.7N 65.2W. Please, see Special Features section for details. A cold front is analyzed from 31N67W to 27N70W to the SE Bahamas near 22N73W. Isolated showers are possible within 120 nm E of the front. Fresh to strong N-NE winds prevail west of the front based on scatterometer and surface data. The front is forecast to become nearly stationary later today with fresh to strong winds persisting west of the front through Wednesday. Cold air stratocumulus clouds are behind the front spreading across Florida and the Bahamas in a NE wind flow. This front has brought the first taste of fall to South Florida. To the SE of the front...Tropical Storm Nicole continues drifting N and covers a large portion of the SW North Atlantic region with cloudiness and ongoing convection. Farther east...an upper level low is noted on water vapor imagery near 32N33W that supports a cold front that enters the forecast area near 31N30W then continues SW then W and NW along 25N40W to 31N52W where it becomes stationary. The front is associated with a 1012 mb low pressure situated near 32N30W. This low will move into the forecast waters reaching a position near 30N36W in about 24 hours. Moderate to fresh southerly winds are within about 120 nm ahead of the front N of 29N. Finally...the eastern Atlantic is under the influence of a surface ridge anchored by a 1022 mb high centered near 33N16W. For additional information please visit http://www.hurricanes.gov/marine $$ GR