Atlantic Tropical Weather Discussion

159
AXNT20 KNHC 092314
TWDAT 
Tropical Weather Discussion
NWS National Hurricane Center Miami FL
0015 UTC Sat Oct 10 2026
Tropical Weather Discussion for North America, Central America
Gulf of America, Caribbean Sea, northern sections of South
America, and Atlantic Ocean to the African coast from the
Equator to 31N. The following information is based on satellite
imagery, weather observations, radar and meteorological analysis.
Based on 1800 UTC surface analysis and satellite imagery through
2100 UTC.
...SPECIAL FEATURES...
Hurricane Isaias is centered near 29.2N 87.0W at 09/2100 UTC or
80 nm S of Pensacola Florida, moving N at 15 kt. Estimated
minimum central pressure is 959 mb. Maximum sustained wind speed
is 100 kt with gusts to 120 kt. Peak seas are up to 37 ft. 
Numerous moderate to scattered strong convection is across the 
eastern Gulf N of 28N between 85W and 88.5W. This convection is 
affecting the western Florida Panhandle and southern Alabama. 
Isaias is moving toward the north, and this general motion is 
expected to continue through Saturday. A north-northeastward to 
northeastward motion is forecast on Sunday. On the forecast 
track, Isaias is expected to make landfall along the coast of the
western Florida Panhandle this evening. The center is then 
expected to move across Alabama and into the Tennessee Valley 
Saturday and Sunday. Isaias is a category 3 hurricane on the 
Saffir-Simpson Hurricane Wind Scale. Little change in strength is
expected before Isaias makes landfall this evening. Weakening is
expected to begin tonight after landfall, and Isaias is forecast
to become post-tropical on Saturday. From Friday through the 
weekend, Isaias is expected to produce rainfall amounts of 4 to 8
inches across southern Alabama, the Florida Panhandle and Big 
Bend, and southwest Georgia. Localized totals up to 15 inches are
possible, particularly within banding across the Florida 
Panhandle and Big Bend. Swells from Isaias are affecting much of 
the Gulf coasts of the United States, Mexico, and western Cuba. 
These swells are likely to cause life-threatening surf and rip 
current conditions. Please consult products from your local 
weather office.
Please read the latest HIGH SEAS FORECAST issued by the National 
Hurricane Center at website - 
https://www.nhc.noaa.gov/text/MIAHSFAT2.shtml and the latest 
Isaias NHC Forecast/Advisory and Public Advisory at 
www.hurricanes.gov for more details.
...TROPICAL WAVES...
A tropical wave is along 28W, south of 19N, moving westward at 5
to 10 kt. Scattered to numerous moderate and isolated strong 
convection is observed mainly on the east side of the wave axis
from 05N to 16N and east of 29W to the coast of Africa.
A western Caribbean tropical wave is along 80W/81W, south of 
20N, moving westward at 10 kt. This wave continues to interact 
with an upper-level low over the NW Caribbean, and is producing 
scattered moderate to isolated strong convection from 13N to 21N
between 75W and 83W. Part of this convective activity is affecting
Jamaica and the Cayman Islands. 
...MONSOON TROUGH/ITCZ...
The monsoon trough enters the Atlantic through the coast of
Mauritania near 18N16W and continues southwestward to 12N30W to 
10N42W. ITCZ extends from 10N42W to near Trinidad and Tobago in
the Windward Islands. In addition to the convection associated
with the tropical wave, scattered moderate convection is evident
from 09N to 14N between 34W and 50W.
...GULF OF AMERICA...
Please read the Special Features section above for more information
on Major Hurricane Isaias centered over the northeast Gulf of 
America. Seas of 8 ft or greater generated by Isaias dominate
most of the easter Gulf, reaching as far south as 23N based on an
altimeter pass. Fresh to strong cyclonic winds spiral into Isaias
from the Yucatan Channel northward between the western Florida 
coastal waters and the central Louisiana coastal waters near 92W.
Elsewhere, a dissipating stationary front extends across N Florida.
Moderate to fresh cyclonic N to NW winds prevail across the western
Gulf, where seas are 4 to 8 ft in NE to E swell from Isaias. 
Scattered showers nd isolated thunderstorms are occurring across
the central Bay of Campeche.
For the forecast, Hurricane Isaias will move inland to near 
31.2N 86.8W late tonight, weaken to a tropical storm well north 
of the area Sat afternoon, and dissipate Mon afternoon. Swells 
generated by Isaias will continue to spread across most of the 
basin through Sat night. In the wake of Isaias, weak high pressure
will develop over the north-central Gulf by Sun evening resulting
in moderate or weaker easterly winds south of about 26N into the
middle of next week.
...CARIBBEAN SEA...
Please read the Tropical Waves section for details on an active
tropical wave in the western Caribbean.
Weak 1019 mb high pressure has shifted southward into the western
Atlantic near 27N67W, to the south of a frontal boundary located
near 30N. The associated pressure gradient is sustaining moderate
to fresh easterly winds and moderate seas across the central
Caribbean mainly N of 12N to the coast of Hispaniola. Moderate to
locally fresh trades and moderate seas are noted over the eastern
Caribbean. Moderate to fresh southerly winds and moderate seas 
are observed west of 84W through the Yucatan Channel, blowing 
into the general circulation of Hurricane Isaias. Light to gentle
winds and seas of 2 to 4 ft are prevalent over the remainder of 
the NW Caribbean as well as over the SW part of the basin. 
For the forecast, a weak pressure gradient is supporting moderate
to fresh trades over the eastern and central Caribbean. Moderate
seas are with these winds. These conditions are expected to 
continue through the next few days. Winds will pulse to strong 
speeds and seas will reach 8 ft tonight through Sun night in the 
south-central Caribbean and Gulf of Venezuela. Meanwhile, a 
tropical wave near 81W, in combination with an upper-level low, 
is producing numerous showers and thunderstorms N of 14N between 
76W and 80W. Unsettled weather conditions will remain associated 
with this wave as it moves across the rest of the western 
Caribbean through the weekend. 
...ATLANTIC OCEAN...
A cold front extends from a 1013 mb low pressure located N of
area near 33N55W to 29N63W then stationary to 30N70W and to NE 
Florida. A weak 1019 mb high is south of this front near 27N67W.
Fresh to strong NE winds and seas of 5 to 7 ft are found north 
of the front off NE Florida and Georgia. South of the front, a 
weak pressure gradient prevails west of 50W, supporting moderate 
or weaker winds and seas of 3 to 5 ft with the exception of
moderate to fresh SE winds N of Hispaniola to about 23N between
68W and 73W. 
An upper-level low is spinning Ne of the Leeward Islands producing
scattered showers and thunderstorms. A surface trough is analyzed
from 30N49W to 21N53W and continues to produce scattered showers
with embedded thunderstorms. The remainder of the Atlantic 
forecast region is under the influence of a 1031 mb high pressure
located just NE of the Azores. The pressure gradient between its
associated ridge and lower pressures in the vicinity of the
monsoon trough supports moderate to fresh winds NE to E winds N 
of the monsoon trough and E of 40W to the coast of W Africa. 
For the forecast west of 55W, the stationary portion of the 
front will lift back N as a warm front tonight into Sat. Fresh to
strong east winds and rough seas are expected off NE Florida 
through Sat night. These winds will veer to the SE at moderate to
fresh speeds early on Sat before weakening to gentle to moderate
speeds by Sun. Otherwise, as high pressure moves across the 
western Atlantic, a tightening pressure gradient will support 
northeast to east winds of fresh to locally strong speeds and 
rough seas behind a cold front over the eastern waters, mainly N 
of 26N, Sun into Mon. Looking ahead, a new cold front is forecast
to push off the U.S. southeastern coast early on Mon and move 
across the waters N of 29N through Wed night while weakening. 
Light to gentle winds and moderate seas will dominate much of the
basin next week.