000 AXNT20 KNHC 031729 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 129 PM EDT Sun Sep 3 2017 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... Hurricane Irma is centered near 17.7N 48.4W at 03/1500 UTC or about 769 nm E of the Leeward Islands moving WSW at 12 kt. Estimated minimum central pressure is 969 mb. Maximum sustained wind speed is 100 kt with gusts to 120 kt. Numerous strong convection is within 90 nm of the center. Scattered moderate to isolated strong convection is elsewhere from 15N-20N between 46W-54W that includes a feeder band over the SW quadrant. Some strengthening is forecast during the next 48 hours. See the latest NHC Forecast/Advisory under AWIPS/WMO headers MIATCMAT1/WTNT21 KNHC for more details. ...TROPICAL WAVES... A tropical wave is in the E Atlantic associated with a 1012 mb low located near 10N32W. The wave axis extends from 16N31W to the low to 05N31W, moving W at 10 kt. The wave is a low amplitude wave. SSMI TPW imagery shows the wave is in a very moist area. The wave is also within a distinct 700 mb trough. Widely scattered moderate convection is over a large area from 04N-13N between 30W- 37W. A tropical wave is in the central Caribbean with axis extending from 22N69W to 10N71W, moving W at 15-20 kt. SSMI TPW imagery shows the wave is in a moderately moist area. The wave is also within a distinct surface and 700 mb trough. Scattered showers are over Hispaniola. Scattered moderate convection is over NW Venezuela, and N Colombia from 07N-11N between 71W-74W. ...ITCZ/MONSOON TROUGH... The monsoon trough extends from the African coast near 12N16W to 10N32W to 12N45W. The ITCZ extends from 12N53W to 11N61W. Besides the convection mentioned with the tropical waves, widely scattered moderate convection is S of the monsoon trough from 05N-09N between 11W-27W. ...DISCUSSION... GULF OF MEXICO... A surface trough is over N Florida and NE Gulf of Mexico from 31N81W to 29N88W. Scattered showers are over the Florida Peninsula. A surface trough is over the Bay of Campeche and S Mexico from 23N93W to 16N93W. Scattered moderate to isolated strong convection is from 18N-22N between 89W-95W. In the upper levels, an upper level low is centered over central Texas near 30N98W. An upper level trough is over the Gulf with axis from the Florida Panhandle to the Yucatan Peninsula. Strong subsidence is over the NE Gulf, while the remainder of the Gulf has upper level moisture. Expect the surface trough over the NE Gulf to remain quasi-stationary over the next 24 hours with continued showers over the Florida Peninsula. Also expect the convection over the Bay of Campeche to persist. CARIBBEAN SEA... A tropical wave is over the central Caribbean producing showers and convection. See above. Elsewhere, the eastern extent of the E Pacific monsoon trough traverses Costa Rica and Panama with scattered moderate convection S of 11N. 10-15 kt tradewinds are over the remainder of the Caribbean Sea. In the upper levels, upper level diffluent flow to the SE of the Gulf of Mexico trough is producing scattered moderate convection over the Yucatan Peninsula, Guatemala, Belize, Honduras and the Gulf of Honduras. Further E, a large upper level ridge is over the central and E Caribbean with strong subsidence. Expect additional convection to advect over the N Caribbean over the next 24 hours. Expect little change elsewhere. ...HISPANIOLA... Scattered showers are presently over the island due to a tropical wave. Expect additional showers and convection to advect over Hispaniola over the next 24 hours. ATLANTIC OCEAN... Hurricane Irma remains the main concern in the basin. See special features for further details. Scattered showers are over the W Atlantic W of 77W to include the N Bahamas. The tail end of a stationary front is over the central Atlantic from 31N60W to 26N67W. Scattered showers are within 90 nm of the front. A 1026 mb high is centered over the central Atlantic near 33N40W. Another 1025 mb high is centered over the E Atlantic near 35N24W. Of note in the upper levels, an upper level low is centered over the W Atlantic near 26N61W. Another upper level low is centered over the E Atlantic near 28N30W. For additional information please visit http://www.hurricanes.gov/marine $$ Formosa