AXNT20 KNHC 211748

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
148 PM EDT Thu Sep 21 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.


At 21/1800 UTC, Hurricane Maria is located near 20.4N 69.4W or about 74 nm ENE of Puerto Plata, Dominican Republic. The present movement of Maria is northwest at 8 kt. The estimated minimum central pressure is 960 mb. Maximum sustained winds are 105 kt with gusts to 130 kt. Numerous strong convection is within 120 nm of the center. Scattered moderate to isolated strong convection is elsewhere within 210 nm of the center. The eye of Hurricane Maria will continue to pass offshore of the northeastern coast of the Dominican Republic today. Maria should then move near the Turks and Caicos Islands and the southeastern Bahamas tonight and Friday. Please see the latest NHC Forecast/Advisory under AWIPS/WMO headers MIATCMAT5/WTNT35 KNHC for more details.

At 21/1800 UTC, Tropical Storm Jose is located about 139 nm SE of Nantucket, Massachusetts near 39.5N 67.9W, stationary. The estimated minimum central pressure is 984 mb. Maximum sustained winds are 50 kt with gusts to 60 kt. Scattered moderate convection prevails mainly in the NW quadrant of the storm from 38N-43N between 70W-74W. Jose is a large system. Tropical-storm-force winds extend outward up to 180 nm from the center. Cool waters, dry air, and an increase in wind shear should cause Jose to steadily weaken and lead to post-tropical transition within the next 24 hours. Please see the latest NHC Forecast/Advisory under AWIPS/WMO headers MIATCMAT2/WTNT22 KNHC for more details.


A tropical wave is in the central Atlantic with axis extending from 19N40W to 07N40W, moving W at 15 kt. The wave is in a region of moderate low to middle level moisture N of 13N, and abundant moisture S of 13N, as shown by SSMI TPW imagery. A well defined surface reflection is also noted. Isolated moderate convection is within 180 nm of the wave axis.


The monsoon trough extends from the African coast near 12N16W to 13N30W to 09N42W. The ITCZ extends from 09N42W to 10N49W to 09N56W to 10N61W. Aside from the convection associated with the tropical wave, widely scattered moderate convection is occurring off of the coast of Africa from 05N-11N E of 24W.



A 1021 mb high is centered over N Alabama near 34N87W. Surface ridging is over the N Gulf of Mexico N of 26N. A very small low is over the central Gulf near 25N88W, depicted by a swirl of low clouds, and scattered showers within 90 nm of the center. Elsewhere, radar imagery shows scattered showers along the coast of Texas, and over the W Gulf W of 94W. More scattered showers are over portions of SE florida. Surface winds over most of the Gulf are only 5-10 kt. The Bay of Campeche has some 15 kt winds. In the upper levels, an upper level high is centered over the SW Gulf near 21N95W. The base of an upper level trough is over the NE Gulf. Expect the surface low to dissipate over the next 12 hours.


The core of Hurricane Maria is over Atlc waters NE of eastern Dominican Republic, however tropical storm winds still reach a portion of NW Puerto Rico. Scattered moderate to isolated strong convection is over Puerto Rico, while numerous strong convection is over the Mona Passage and the Dominican Republic. Puerto Rico continues to have localized flooding. See the special features section for further details. Strong winds and high seas associated with Maria prevail in the NE Caribbean mainly N of 16N. The eastern extent of the Pacific monsoon trough extends across Costa Rica, Panama through Colombia supporting isolated showers and tstms in the SW Caribbean S of 12N. Of note in the upper levels, a sharp upper level trough is over the NW Caribbean with axis from central Cuba near 22N79W to central Honduras near 14N86W. Some scattered showers are Just E of the trough axis due to upper level diffluence. Expect winds and seas associated with Maria to gradually diminish through Friday as the cyclone moves farther NW over the SW N Atlc waters.


A hurricane warning prevails for portions of the northern Dominican Republic while a tropical storm warning is in effect for Haiti. A dangerous storm surge accompanied by large and destructive waves will raise water levels by as much as 4-6 feet above normal tide levels in the hurricane warning area in the Dominican Republic, and 1-3 ft elsewhere along the northern coasts of the Dominican Republic and Haiti. Please see the latest NHC Forecast/Advisory. Numerous strong convection is occurring over the Dominican Republic spreading across the rest of the Island as Maria continues to move NW over SW N Atlc waters.


Please refer to Special Features section for more information on Hurricane Maria and Tropical Storm Jose. A 1012 mb low, the remnants of Lee, is located near 19N48W. A surface trough extends N from the low to 25N50W. Widely scattered moderate convection is from 21N-25N between 45W-49W. The remainder of the basin remains under the influence of a broad Bermuda-Azores high centered north of the area. Of note in the upper levels, a large upper level low is centered near 24N49W. Scattered moderate convection is NE of this center from 27N-31N between 39W-45W due to upper level diffluence.

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

$$ Formosa