AXNT20 KNHC 232112
Tropical Weather Discussion
NWS National Hurricane Center Miami FL
0005 UTC Sun Sep 24 2023
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 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
Tropical Storm Ophelia is centered over SE Virginia near 36.8N
77.3W at 23/2100 UTC or 40 nm S of Richmond Virginia, moving N at
10 kt. Estimated minimum central pressure is 997 mb. Maximum
sustained wind speed is 35 kt with gusts to 45 kt. Peak seas which
are N of the area are currently around 16 ft offshore Hampton
Roads and also SE of New Jersey. Numerous moderate convection is
noted within 45 nm of the center, except out to 120 nm in the NE
quadrant of Ophelia. Additional convection extends well away from
the system. On the forecast track, the center of Ophelia is
expected to continue moving over southeastern Virginia through
tonight, and then over the Delmarva Peninsula by tomorrow. Ophelia
is likely to become a post-tropical cyclone tomorrow. Swells
generated by Ophelia will continue to affect much of the east
coast of the United States through the weekend. These swells are
likely to cause life-threatening surf and rip current conditions.
Please consult products from your local weather office. Heavy
rainfall from Ophelia may produce locally considerable flash and
urban flooding impacts across portions of the Mid-Atlantic states
from North Carolina to New Jersey through Sunday.
Recently upgraded Tropical Storm Philippe is centered near 15.6N
39.7W at 23/2100 UTC or 910 nm W of the Cabo Verde Islands, moving
W at 12 kt. Estimated minimum central pressure is 1005 mb.
Maximum sustained wind speed is 35 kt with gusts to 45 kt. Peak
seas with Philippe are 14-15 ft. Numerous moderate scattered
strong convection is noted within 150 nm in the NE semicircle.
Scattered moderate convection is noted elsewhere from roughly 13N
to 21N between 30W and 42W. A continued westward motion at a
slightly slower forward speed is expected into early next week.
Very gradual strengthening is expected during the next several
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
Philippe NHC Forecast/Advisory and Public Advisory at
www.hurricanes.gov for more details on both Ophelia and Philippe.
A tropical wave is in the eastern Atlantic Ocean between the coast
of Africa and the Cabo Verde Islands along 20W/21W, from 20N
southward, moving W at around 10 kt. No significant convection is
A tropical wave is in the eastern Caribbean Sea along 65W/66W
from near the Anegada Passage southward to central Venezuela,
moving W at around 10 kt. No significant convection is noted.
The monsoon trough passes through the coastal plains of
Guinea-Bissau near 12N16W to 10N24W to 14N34W. No ITCZ is analyzed
in the Atlantic Ocean. Scattered moderate isolated strong
convection is noted from 07N to 14N between 25W and 29W, and from
05N to 07N between 44W and 50W.
...GULF OF MEXICO...
An elongated surface trough extends from the NW Caribbean through
near the Yucatan Channel to the eastern Gulf near 27N86W. This
surface feature combined with mid to upper level support is aiding
scattered showers and thunderstorms S of 26N and E of 87W.
Otherwise fair weather prevails across the basin. Gentle to
moderate NE-E winds and 2-4 ft seas prevail E of 90W near the
surface trough, with light to gentle winds and 1-3 ft seas W of
For the forecast, the surface trough over the southeast Gulf
will drift slowly into the western Gulf through early next week
and dissipate. Meanwhile, weak high pressure will persist over the
north-central and northeast Gulf. This pattern will support
gentle to moderate NE to E winds and slight seas across the basin
through the middle of next week.
Refer to the Tropical Waves section for details on a tropical wave
in the eastern Caribbean. A surface trough extends from the SE
Gulf of Mexico into the NW Caribbean Sea with some isolated to
widely scattered showers and thunderstorms near it. Thunderstorms
are prevalent from W of Haiti to between Cuba and Jamaica aided
by a mid to upper level trough. Light to gentle winds are evident
W of 80W, with moderate trades E of 80W, except fresh offshore NW
Venezuela and N Colombia. Seas are 1-3 ft in the NW Caribbean, and
3-6 ft elsewhere, highest in the central Caribbean.
For the forecast, the Atlantic high pressure will support
moderate to fresh trade winds across most of the eastern and
central Caribbean through early next week, with fresh to strong
pulses off northwest Venezuela and northeast Colombia during
mainly the overnight and early morning hours. Looking ahead, seas
will build in mixed NE and E swell across waters east of the
Leeward Islands starting Mon, ahead of newly formed Tropical Storm
Philippe, currently over the eastern Atlantic. Philippe is
expected to turn NW before reaching 55W next week, and move into
the central Atlantic.
Refer to the Special Features section for details on Tropical
Storm Ophelia and recently upgraded Tropical Storm Philippe.
Scattered showers and thunderstorms are noted from 20N to 31N
between 70W and 80W due to a mid to upper level trough. Similar
activity is from 22N to 28N between 53W and 60W. Elsewhere, high
pressure ridging in the wake of Ophelia dominates the Atlantic
waters. Mainly gentle to moderate trades prevail away from
Philippe, locally fresh from 14N to 25N between the coast of
Africa and 55W, and also from 25N to 31N between 55W and 75W. Seas
if 5-8 ft dominate the Atlantic basin away from Philippe.
For the forecast W of 55W, large northerly swell from Ophelia,
now inland over SE Virginia, will continue to impact the waters N
of 29N and W of 70W through this evening. A weak ridge has built
into the central Bahamas in the wake of Ophelia and will persist
through early next week, while a trough will persist across the
northern Bahamas through Mon. Looking ahead, seas will build in
mixed NE and E swell across waters northeast of the Leeward
Islands starting Mon, ahead of Tropical Storm Philippe. Tropical
Storm Philippe is expected to turn NW by Tue and brush along the
far eastern zones on Wed and Thu.