NHC Tropical Weather Discussion (Atlantic) National Hurricane Center - Tropical Weather Discussion (Atlantic)

  • NHC Atlantic Tropical Weather Discussion

    000 AXNT20 KNHC 190005 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 805 PM EDT Thu Oct 18 2018 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 2330 UTC. ...SPECIAL FEATURES... ...GALE-FORCE WINDS ARE IN THE GULF OF MEXICO... A cold front reaches 29N80W in the Atlantic Ocean. The front is stationary from 29N80W, across Florida to 28N90W in the Gulf of Mexico, to 28N96W, and then curving to the coast of Mexico in the SW corner of the Gulf of Mexico at the northern part of the Isthmus of Tehuantepec 18N94W. The HIGH SEAS FORECAST consists of: NW-to-N GALE-FORCE winds and sea heights ranging from 8 feet to 14 feet S of 21N W of 94W. Expect these conditions to be weakening and wind speeds less than GALE-FORCE during the next hour or so. Please read the HIGH SEAS FORECAST, listed as MIAHSFAT2/FZNT02 KNHC, for more details ...TROPICAL WAVES... An Atlantic Ocean tropical wave is along 14N39W to 10N41W to 04N44W. Scattered moderate to isolated strong convection is from 05N-11N between 36W-48W. A Caribbean Sea tropical wave is along 70W from 05N-21N, moving west at 10-15 kt. A 700 mb trough is associated with the wave, and there is a local maximum in SSMI TPW. Scattered moderate convection is from 12N-15N between 68W-72W. A Caribbean Sea tropical wave is along 88W from 07N-21N, moving W at 15 kt. SSMI TPW imagery shows a distinct maximum in moisture around the wave axis. Scattered moderate convection is from 17N- 21N between 81W-85W, and from 09N-15N between 82W-89W. ...MONSOON TROUGH/ITCZ... The monsoon trough passes through the coastal sections of Guinea near 10N14W to 06N18W. The ITCZ continues from 06N18W to 05N28W and 08N40W, and from 08N44W to 07N54W to 09N60W. Widely scattered moderate to isolated strong rainshowers are within 120 nm to 180 nm on either side of the line that runs from 07N12W to 05N21W to 02N34W. GULF OF MEXICO... A cold front reaches 29N80W in the Atlantic Ocean. The front is stationary from 29N80W, across Florida to 28N90W in the Gulf of Mexico, to 28N96W, and then curving to the coast of Mexico in the SW corner of the Gulf of Mexico at the northern part of the Isthmus of Tehuantepec 18N94W. Widely scattered moderate to isolated strong rainshowers are in the NW corner of the Gulf of Mexico, from 24N northward from 92W westward. Isolated moderate rainshowers are elsewhere from 26N southward from 85W westward. A cold front extends from 29N83W to 28.5N88W then continues as stationary front across the western Gulf to 27N95W to 23N96W to 18N94W. Gale force northerly winds behind the front will persist in the SW Gulf through this afternoon. Winds will diminish below gale force tonight as the front weakens and becomes diffuse. A new cold front will enter the Gulf waters Sat. The front will stall from south Florida to southern Texas Sun night, then lift N through early next week. CARIBBEAN SEA... An upper level trough passes through 20N58W in the Atlantic Ocean, across the NE part of the Caribbean Sea, to Hispaniola and the Windward Passage, to an upper level cyclonic circulation center that is in Belize and northern Guatemala. Comparatively drier air in subsidence covers the Caribbean Sea from 16N northward from 70W eastward. An upper level trough also extends from the Windward Passage toward NW Venezuela that is along 70W. Isolated to widely scattered moderate rainshowers, some dissipating, are from Hispaniola southward, between 70W and 76W. Moderate to fresh trade winds will prevail during the next several days. Expect also: locally strong near the approach to Windward Passage, S of Hispaniola, and in the Lee of eastern Cuba through the end of the week, and then returning near the approach to Windward Passage and S of Hispaniola next week. ATLANTIC OCEAN... A cold front enters the W Atlantic near 31N65W and extends to N Florida near 29N81W. Scattered showers are within 90 nm of the front. A surface trough is over the central Atlantic from 30N49W to 21N51W. The position is based on a recent ASCAT imagery that depicts the trough axis. Scattered showers are within 240 nm of the trough axis. A backdoor cold front will extend from 30N65W to 29N81W by tonight. Fresh to locally strong NE winds and building seas can be expected behind the front through Fri before decreasing Sat. Another cold front will cross waters offshore N Florida Sat night with increasing winds and building seas behind the front through Mon, with the front weakening by Mon night as it reaches from 26N65W to 24N80W. For additional information please visit http://www.hurricanes.gov/marine $$ mrf/latto/mt […]