AXNT20 KNHC 240531

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
131 AM EDT Sun Sep 24 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 0000 UTC surface analysis and satellite imagery through 0530 UTC.


Hurricane Maria is centered near 27.0N 72.5W at 24/0300 UTC or about 248 nm east of Great Abaco Island, moving north at 8 kt. Estimated minimum central pressure is 942 mb. Maximum sustained wind speed is 100 kt with gusts to 120 kt. Scattered to numerous moderate convection is from 24N-31N between 68W-76W. See the latest NHC Forecast/Advisory under AWIPS/WMO headers MIATCMAT5/WTNT25 KNHC for more details.

Tropical Storm Lee is centered near 32.1N 49.8W at 24/0300 UTC or about 747 nm east of Bermuda, moving south-southeast at 1 kt. Estimated minimum central pressure 1003 mb. Maximum sustained wind speed is 45 kt with gusts to 55 kt. Scattered moderate convection is from 31N-34N between 49W-52W. See the latest NHC Forecast/Advisory under AWIPS/WMO headers MIATCMAT4/WTNT24 KNHC for more details.


A tropical wave extends its axis from 22N23W to 07N25W, moving west at 5-10 kt. The wave coincides with a 700 mb low, the northern vortex, centered near 21N21W. No significant deep convection is associated with the wave axis at this time. The ongoing convection is related to the monsoon trough axis and will be mentioned below.

A tropical wave extends its axis from 19N57W to 06N58W moving west at 10-15 kt. The wave remains on the southwestern periphery of a 700 mb ridge anchored near 22N40W and lies beneath an upper level trough axis extending along 53W. Scattered moderate convection is observed from 08N-20N between 53W-58W.


The monsoon trough axis extends from the African coast near 14N17W to 07N30W. The ITCZ extends from 07N30W to 07N55W. Scattered moderate convection prevails along the monsoon trough and in the vicinity of the ITCZ near the tropical wave over the central Atlantic mainly west of 52W.



A mid to upper-level low is noted on water vapor imagery centered over southern Alabama near 32N86W with a trough axis extending southward over the eastern Gulf to a broad base over the Yucatan peninsula and northwest Caribbean. A weak pressure pattern across the basin is resulting in gentle to moderate easterly winds with areas of isolated showers generally occurring north of 26N and east of 88W under the influence of the middle to upper level lifting dynamics in place. Elsewhere, dry and stable northerly flow aloft and generally gentle to moderate easterly winds are providing for fair conditions and mostly clear skies. Through the remainder of the weekend into the middle of next week, little change is expected in overall conditions.


West-southwesterly flow aloft prevails west of 73W as Hurricane Maria is well north of the basin and an overall weak pressure pattern remains in place across the central and western Caribbean. As a result of the weaker pressure pattern, winds remain generally light to gentle and variable at times. A couple of weak surface troughs are analyzed, one from the coast of central Cuba near 22N80W to 19N83W, and the other extending south of Hispaniola near 18N70W to 15N72W. Scattered moderate convection is observed in the vicinity of the second trough affecting the waters south of 14N between 71W-77W. A tropical wave currently along 58W will continue approaching the Lesser Antilles through the weekend increasing the probability of convection across the islands and adjacent waters.


A surface trough currently extends from the south-central coast near 18N70W to 15N72W and continues to provide focus for isolated showers across the southeastern portion and south coast of the island. The troughing will slide westward through the weekend as weak ridging builds in from the central Atlantic from the east.


Outside the influence of Maria across the west Atlantic waters, surface ridging prevails across much of the remainder of the basin. A 1020 mb high is centered near 34N57W, and a 1021 mb high is centered across the central Atlantic near 28N39W. Between these two highs, Tropical Storm Lee continues to influence the waters from 30N-33N between 48W-52W. In addition, a mid to upper-level trough extends along 52W enhancing convection from 20N-25N between 50W-53W.

For additional information please visit http://www.hurricanes.gov/marine